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1
Kursuncu, Bilal, Halil Caliskan, Sevki Yilmaz Guven, and Peter Panjan. "Wear Behavior of Multilayer Nanocomposite TiAlSiN/TiSiN/TiAlN Coated Carbide Cutting Tool during Face Milling of Inconel 718 Superalloy." Journal of Nano Research 47 (May 2017): 11–16. http://dx.doi.org/10.4028/www.scientific.net/jnanor.47.11.
Анотація:
The Inconel 718 superalloy is one of the most-used nickel based superalloys in the aerospace industry due to its superior mechanical properties, for instance, high thermal and chemical resistance, and high strength at elevated temperatures. However, the work hardening tendency, low thermal conductivity and high hardness of this superalloy cause early tool wear, leading to the material to be called as a hard-to-cut material. Therefore, deposition of a wear resistant hard coating on carbide cutting tools has a critical importance for longer tool life in milling operations of the Inconel 718 superalloy. In this study, carbide cutting tools were coated with multilayer nanocomposite TiAlSiN/TiSiN/TiAlN coating using the magnetron sputtering technique, and wear behavior of the coated tool was investigated during face milling of the Inconel 718 superalloy under dry conditions. Abrasive and adhesive wear mechanisms were founded as main failure mechanisms. The nanocomposite TiAlSiN/TiSiN/TiAlN coated carbide cutting tool gave better wear resistance, and thus it provided 1.7 times longer tool life and a smoother surface (Ra<0.18 μm) on the Inconel 718 material than the uncoated one.
2
Pan, Lei, ZR Wu, Lei Fang, and YD Song. "Investigation of surface damage and roughness for nickel-based superalloy GH4169 under hard turning processing." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 234, no. 4 (November 16, 2019): 679–91. http://dx.doi.org/10.1177/0954405419885789.
Анотація:
Machined surface condition of nickel-based superalloys has an important influence on the functional performance of the components. Proper selection of cutting parameters could improve surface finish and increase service life of parts and components. This research work bases on an experimental and statistical study of turning GH4169 nickel-based superalloy with cemented carbide tool. Surface damages like feed marks, tips, and surface tearing were discussed. The second-order polynomial model was used to describe the surface roughness response. Variance analysis was selected to eliminate the insignificant variables in the roughness model. The response surface methodology was used to investigate the combined effect of cutting parameters on two different dimensions surface roughness parameters. The optimization of cutting parameters for minimum surface roughness was obtained using desirability function method. The results demonstrate that feed rate has the most significant effect on surface roughness. High cutting speed and low feed rate result in better surface quality, but too low feed rate exacerbates built-up edge phenomenon and deteriorates surface condition. Optimal cutting parameters leading to the minimum surface roughness were highlighted.
3
Prasad, Ganesha, Raghavendra Kamath C., and Vijay G.S. "A review on conventional and nonconventional machining of Nickel-based Nimonic superalloy." Manufacturing Review 10 (2023): 10. http://dx.doi.org/10.1051/mfreview/2023009.
Анотація:
Superalloys have gained prominence in recent years in various sectors, namely, spacecraft, marine, power, defense, vehicular and others, due to their ability to withstand high temperatures of up to 980 °C without deformation. Nimonics are Nickel-based superalloys usually known to be hard-to-machine materials due to their high strength at high temperatures, higher hardness, low thermal conductivity, and tendency to react with tool material. All these factors increase the level of difficulties in the machining of Nimonic superalloys. Numerous studies have examined various facets of machining of Nimonic alloys. This article summarizes the observation from 152 research articles to offer a reasonable engineering overview of the study of Nimonic alloys. An overview of Nimonic superalloys and their applications is given first. Then, various conventional and non-conventional machining processes, problems associated with multiple machining processes and methods to rectify the issues concerning the machining process have been reported. Thus, this summary will certainly help industrialists and academic researchers for further research work in machining Nimonic alloys.
4
Zahedi, Ali, and J. Akbari. "FEM Analysis of Single Grit Chip Formation in Creep-Feed Grinding of Inconel 718 Superalloy." Advanced Materials Research 325 (August 2011): 128–33. http://dx.doi.org/10.4028/www.scientific.net/amr.325.128.
Анотація:
Recent advances in materials science have necessitated the development and understanding of manufacturing processes for safe and repeatable utilization. Grinding is shown to be a promising material removal process especially for brittle and hard to cut materials such as superalloys. Grinding has always been associated with analysis and modeling complications regarding its nature which has limited its extension and reliability of use. The first step in analysis of grinding is considering the action of a single abrasive grit on workpiece surface. In this work the action of a single CBN abrasive grit in creep-feed grinding process of Inconel 718 superalloy is modeled and analyzed using a 3D FEM software, DEFORM. Thermal and mechanical characteristics of the mutual interaction between grit and workpiece surface, and different chip formation phases are defined which can further be used to analyze the whole process.
5
Díaz-Álvarez, José, Antonio Díaz-Álvarez, Henar Miguélez, and José Cantero. "Finishing Turning of Ni Superalloy Haynes 282." Metals 8, no. 10 (October 18, 2018): 843. http://dx.doi.org/10.3390/met8100843.
Анотація:
Nickel-based superalloys are widely used in the aeronautical industry, especially in components requiring excellent corrosion resistance, enhanced thermal fatigue properties, and thermal stability. Haynes 282 is a nickel-based superalloy that was developed to improve the low weldability, formability, and creep strength of other γ’-strengthened Ni superalloys. Despite the industrial interest in Haynes 282, there is a lack of research that is focused on this alloy. Moreover, it is difficult to find studies dealing with the machinability of Haynes 282. Although Haynes 282 is considered an alloy with improved formability when compared with other nickel alloys, its machining performance should be analyzed. High pressure and temperature localized in the cutting zone, the abrasion generated by the hard carbides included in the material, and the tendency toward adhesion during machining are phenomena that generate extreme thermomechanical loading on the tool during the cutting process. Excessive wear results in reduced tool life, leading to frequent tool change, low productivity, and a high consumption of energy; consequentially, there are increased costs. With regard to tool materials, cemented carbide tools are widely used in different applications, and carbide is a recommended cutting material for turning Haynes 282, for both finishing and roughing operations. This work focuses on the finishing turning of Haynes 282 using coated carbide tools with conventional coolant. Machining forces, surface roughness, tool wear, and tool life were quantified for different cutting speeds and feeds.
6
Mukhtarov, Shamil, Artem Ganeev, Marsel Nagimov, Ruslan Shakhov, Vener Valitov, and Farid Utyashev. "Manufacturing of Axisymmetric Components out of Superalloys and Hard-to-Deform Steels by Roll Forming." Key Engineering Materials 746 (July 2017): 69–74. http://dx.doi.org/10.4028/www.scientific.net/kem.746.69.
Анотація:
Heat-resistant alloys are the basic material of gas turbine engine (GTE) design. Fine-grained structure in these alloys can be formed by isothermal forging and then different axisymmetric GTE components as wheels, shafts, rings can be superplastic roll formed. Examples of the superplastic and isothermal deformation use for manufacturing components out of superalloys and steels for critical applications are given. The possibility of roll forming parts as rings with a diameter up to 800 mm and as flange - cone with a diameter up to 600 mm out of superalloys (Inconel 718, EK79, EP741NP), accordingly, on SRZHD-800 and modified PNC-600 mills were showed. The macrostructure investigations of the components after the roll forming showed that the homogeneous structure was formed. The microstructure at the flange portion was fine-grained and at membrane zone was coarse-grained. Cone part was roll formed at isothermal condition from pre-stamped chromium martensitic steel sheet. Manufacturing technology of roll forming was tested by computer and physical simulation. Service properties of components were obtained by subsequent heat treatment. The effectiveness of the technology associated with increased service properties of components and decreases the labor content by automated equipment.
7
ALTIN, Abdullah. "Determination of Cutting Tool Performance Characteristics in Machining Nickel Based Super Alloys." International Conference on Applied Engineering and Natural Sciences 1, no. 1 (July 20, 2023): 416–20. http://dx.doi.org/10.59287/icaens.1031.
Анотація:
Cutting tool materials often undergo severe mechanical stresses and thermal changes when machining nickel-based superalloys. The stresses and temperatures that arise when machining nickel-based superalloys greatly increase the blunting and wear rate of the cutting tool. As a result, tool life is adversely affected. It is seen from important studies that adhesion and abrasion wear mechanisms are more dominant in the processing of Inconel 718. The work material adheres to the cutting edge, forming a BUE. Depending on the cutting conditions, stable BUE is not always formed and this layer is sometimes repeatedly removed with the chips. Notching in the depth of cut, wear on the tool nose and coating layer is caused by the presence of hard particles in Inconel 718 and causes severe flank wear. Flank wear and notch are the main factors limiting tool life, and oxidation and diffusion occur as a result of high temperatures.
8
Jean, Ming-Der, Shu-Yi Tu, and Jen-Ting Wang. "Analysis of Hard-Facing Appearance of Specific Powdered Superalloys for PTA-Coating Processes." Journal of Materials Engineering and Performance 14, no. 3 (June 1, 2005): 307–14. http://dx.doi.org/10.1361/10599490523904.
9
Díaz-Álvarez, Antonio, José Díaz-Álvarez, José Luis Cantero, and Henar Miguélez. "Sustainable High-Speed Finishing Turning of Haynes 282 Using Carbide Tools in Dry Conditions." Metals 9, no. 9 (September 6, 2019): 989. http://dx.doi.org/10.3390/met9090989.
Анотація:
Nickel-based superalloys exhibit an exceptional combination of corrosion resistance, enhanced mechanical properties at high temperatures, and thermal stability. The mechanical behavior of nickel-based superalloys depends on the grain size and the precipitation state after aging. Haynes 282 was developed in order to improve the creep behavior, formability, and strain-age cracking of the other commonly used nickel-based superalloys. Nevertheless, taking into account the interest of the industry in the machinability of Haynes 282 because of its great mechanical properties, which is not found in other superalloys like Inconel 718 or Waspaloy, more research on this alloy is necessary. Cutting tools suffer extreme thermomechanical loading because of the high pressure and temperature localized in the cutting zone. The consequence is material adhesion during machining and strong abrasion due to the hard carbides included in the material. The main recommendations for finishing turning in Haynes 282 include the use of carbide tools, low cutting speeds, low depth of pass, and the use of cutting fluids. However, because of the growing interest in sustainable processes and cost reduction, dry machining is considered to be one of the best techniques for material removal. During the machining of Haynes 282, at both the finishing and roughing turning, cemented carbide inserts are most commonly used and are recommended all over the industry. This paper deals with the machining of Haynes 282 by means of coated carbide tools cutting fluids (dry condition). Different cutting speeds and feeds were tested to quantify the cutting forces, quality of surface, wear progression, and end of tool life. Tool life values similar to those obtained with a lubricant under similar conditions in other studies have been obtained for the most favorable conditions in dry environments.
10
Li, Yuebing, Yanming He, Chuanyang Lu, Wenjian Zheng, Jianguo Yang, Donghong Wang, Limei Wang, Yuan Sun, and Zengliang Gao. "Microstructural Evolution and Mechanical Evaluation of a Laser-Induced Composite Coating on a Ni-Based Superalloy during Thermal Exposure." Materials 12, no. 9 (May 3, 2019): 1439. http://dx.doi.org/10.3390/ma12091439.
Анотація:
A Ni–17Mo–7Cr-based superalloy was laser surface-modified to improve its tribological properties. Si particles were employed as coating materials. Si melted on the surface of the alloy during the process, triggering the formation of Mo6Ni6C carbides and Ni–Si intermetallics. A defect-free coating obtained was mostly made up of primary Mo6Ni6C and γ-Ni31Si12, as well as a eutectic structure of β1-Ni3Si and α-Ni-based solid solution (α-Ni (s.s)). The volume fraction of hard reinforcements (Mo6Ni6C, γ-Ni31Si12, and β1-Ni3Si) reached up to 85% in the coating. High-temperature microstructural stability of the coating was investigated by aging the coating at 1073 K for 240–480 h, to reveal its microstructural evolution. In addition, the mechanical performance of the coating was investigated. The nanoscale elastic modulus and hardness of Mo6Ni6C, γ-Ni31Si12, and α-Ni (s.s) were characterized using the nanoindentation tests. The nanoscratch tests were performed to measure the local wear resistance of the coating. Lastly, the Vickers hardness distribution across the cross-section of the coating before and after thermal exposure was compared. The work performed provides basic information understanding the microstructural evolution and mechanical performance of laser-induced coatings on Ni-based superalloys.
11
Poloczek, Tomasz, Aleksandra Lont, and Jacek Górka. "The Structure and Properties of Laser-Cladded Inconel 625/TiC Composite Coatings." Materials 16, no. 3 (February 1, 2023): 1265. http://dx.doi.org/10.3390/ma16031265.
Анотація:
This article presents production results concerning metal matrix composite-coatings made using the laser-cladding technology. The enhancement of the wear resistance of the material surface is the one of the main goals accompanying the manufacturing of composite coatings. Nickel-based superalloys are used in several industries because they are characterized by a number of desirable properties including high tensile and fatigue strength as well as resistance to high-temperature corrosion in aggressive environments. One of the most interesting materials from the group of superalloys is Inconel 625, used as a matrix material in tests discussed in this article. However, nickel-based superalloys are also characterized by an insufficient wear resistance of the surface, therefore, in relation to the tests discussed in this article, Inconel 625-based composite coatings were reinforced by adding 10%, 20% and 40% of titanium carbide particles. The addition of hard phases, i.e., TiC, WC or SiC particles can have a positive effect on the erosion resistance of cladded specimens. The aim of the experiment was to determine the impact of the titanium carbide content on the structure of the alloy and its resistance to corrosive wear, enabling the extension of the service life of Inconel 625/TiC composite coatings. The investigation included microhardness tests, corrosion resistance analysis, penetrant tests, macrostructure and microstructure analyses and X-ray diffraction (XRD) tests. The TiC particles increased the hardness of the coatings and, in general, had a negative impact on the corrosion resistance of pure Inconel 625 coatings. However, the increased homogeneity of composite coatings translated into the improvement of corrosion resistance.
12
Zheng, Jia, Chuan Tang, Yuanxi Sun, Mingchi Feng, and Congzhe Wang. "An Enhanced U-Net Approach for Segmentation of Aeroengine Hollow Turbine Blade." Mathematics 10, no. 22 (November 12, 2022): 4230. http://dx.doi.org/10.3390/math10224230.
Анотація:
The hollow turbine blade plays an important role in the propulsion of the aeroengine. However, due to its complex hollow structure and nickel-based superalloys material property, only industrial computed tomography (ICT) could realize its nondestructive detection with sufficient intuitiveness. The ICT detection precision mainly depends on the segmentation accuracy of target ICT images. However, because the hollow turbine blade is made of special superalloys and contains many small unique structures such as film cooling holes, exhaust edges, etc., the ICT image quality of the hollow turbine blades is often deficient, with artifacts, low contrast, and inhomogeneity scattered around the blade contour, making it hard for traditional mathematical model-based methods to acquire satisfying segmentation precision. Therefore, this paper presents a deep learning-based approach, i.e., the enhanced U-net with multiscale inputs, dense blocks, focal loss function, and residual path in the skip connection to realize the high-precision segmentation of the hollow turbine blade. The experimental results show that our proposed enhanced U-net can achieve better segmentation accuracy for practical turbine blades than conventional U-net and traditional mathematical model-based methods.
13
Danzer, Robert, Markus Lengauer, Domagoj Rubeša, and Walter Harrer. "Silicon Nitride Tools for Hot Rolling of High-Alloyed Steel and Superalloy Wires." Key Engineering Materials 409 (March 2009): 43–54. http://dx.doi.org/10.4028/www.scientific.net/kem.409.43.
Анотація:
For hot rolling wires of high-alloyed steels or superalloys tools are nowadays made of ce¬mented carbides. In service they suffer from roughening of the surfaces and severe wear, which de¬teriorates the surface quality of the wires and restricts the lifetime of the tool. Due to their high hard¬ness and good high-temperature properties, improvements in tool behaviour can be expected by the use of silicon nitride tools. Experiments with several types of rollers were performed in commercial rolling mills. At modest and medium severe loaded positions (e.g. in the case of guidance rolls) silicon nitride rolls show superior performance to conventional steel or cemented carbide rolls. At the most severe loaded positions silicon nitride rolls were also superior to conventional rolls when rolling high strength steel wires. But for rolling superalloy wires, cracks, which limited further applications of the rolls, appeared in the roll surface profile (calibre). Cracks in the surface of the rollers are in general caused by Hertzian contact stresses, which can reach several hundred MPa. These cracks come into existence if a limiting load is exceeded. Then small flaws can quickly extend to a length of more then one millimetre, and then they stop again (pop in behaviour). Popped in cracks can slowly extend by cyclic fatigue up to a length where breaking out of large fragments of the rollers occurs. The critical load depends on the flow curve of the rolled materials and on the design of the rolls. For the analysed design it is exceeded when rolling superalloy wires, but it is not exceeded when rolling materials having a lower flow curve.
14
Beranoagirre, A., and Luis Norberto López de Lacalle. "Optimizing the Turning of Titanium Aluminide Alloys." Advanced Materials Research 498 (April 2012): 189–94. http://dx.doi.org/10.4028/www.scientific.net/amr.498.189.
Анотація:
The work here exposed, is framed in the line of development of slight materials with good properties, used to reduction of weight in different components for the aviation and automotion where very high temperatures are the main factor. In these fields, several components must withstand high temperatures maintaining a high resistance. The superalloys of type Gamma TiAl is a attractive alternative to other titanium and nickel-based alloys, due to high relationship resistance/weigh and the resistance to the corrosion. This work presents the results from turning tests on three types of Gamma TiAl alloys. Coating tools of integral hard metal are used, with different advances and cut speeds.
15
Gadalińska, Elżbieta, Andrzej Michałowski, and Sławomir Czarnewicz. "Determination of Stress Values in the Surface Layer of Inconel 718 Samples Dedicated to Fatigue Tests." Fatigue of Aircraft Structures 2019, no. 11 (December 1, 2019): 78–86. http://dx.doi.org/10.2478/fas-2019-0008.
Анотація:
AbstractThis work deals with the problem of X-ray stress determination on the samples dedicated to fatigue tests. A number of research studies point out the fact that the processing of hard, difficult to machine materials like nickel superalloys, reveals more than one trend of residual stress versus working parameters of behaviour (Lavella and Berruti, 2010). Many papers have shown that the residual stresses are dependent on a combination of a number of factors. When the above is taken into account simultaneously with the requirements of the internal General Electric specification for the fatigue tests samples preparation (Metallic test specimen preparation, low stress, 2017) the problem of turning and grinding parameters gathers significance. It is well known that the quality of the surface layer, produced during machining, is of vital importance for the fatigue life specially for the components of aircraft produced form nickel superalloys e.g. Inconel 718 (Kortabarri et al., 2011). That is why the surface layer’s properties are described in detail by the standards. The aim of the work is to determine one of the most influential features from the point of view of fatigue life, i.e. the stress state on the surface layer with one non-destructive method – the diffraction analysis.
16
Memarianpour, Morvarid, Seyed Ali Niknam, Sylvain Turenne, and Marek Balazinski. "Initial tool wear behavior in high-speed turning of Inconel 718." Transactions of the Canadian Society for Mechanical Engineering 44, no. 3 (September 1, 2020): 395–404. http://dx.doi.org/10.1139/tcsme-2019-0110.
Анотація:
Three distinctive regions of tool wear, known as initial wear, steady-state wear, and accelerated wear, are well understood. However, the effects of cutting parameters on the initial tool wear mechanism, morphology, and size have received less attention as compared to the other two regions. Knowing that adequate control of initial tool wear may lead to extended tool life, in particular in hard-to-cut metals such as superalloys, this topic has become a source of attention. Amongst superalloys, Inconel 718 is considered as one of the most difficult to cut materials, which has a wide range of industrial applications. This study intends to evaluate the effects of cutting parameters on initial tool wear, as well as tool wear progression, when turning Inconel 718. Therefore, microstructural evaluation of the initial tool wear mode under various cutting conditions, as well as tool wear measurements, were conducted. It was observed that certain elements of the workpieces were migrated to the insert flank face. This is evidence of adhesion at the initial moments of the cutting process. In contrast to many other easy-to-cut materials, the steady-state wear period when turning Inconel 718 is significantly short under a higher level of cutting speed and feed rate.
17
Chang, Julius C., and Samuel M. Allen. "Elstic energy changes accompanying gamma-prime rafting in nickel-base superalloys." Journal of Materials Research 6, no. 9 (September 1991): 1843–55. http://dx.doi.org/10.1557/jmr.1991.1843.
Анотація:
Eshelby's equivalent inclusion method is applied to the case of a single, inhomogeneous, ellipsoidal precipitate in an infinite matrix to study the morphological changes of the gamma-prime precipitates in nickel-base superalloys due to the influence of lattice constant misfit, elastic inhomogeneity and anisotropy, applied stress, and interfacial energy. The energy-minimizing inclusion shapes depend very sensitively on the degree of elastic inhomogeneity, on the sense and magnitude of the applied stress, and on the sense of the lattice constant misfit. The interfacial energy contribution can dominate that of elastic strain energy for small precipitate sizes, elastically compliant systems, nearly homogeneous alloys, and/or nearly isotropic materials. Calculations are carried out for two well-characterized nickel-base alloys: a Ni–13.5Al alloy (positive misfit, elastically hard inclusions) studied by Miyazaki et al. and CMSX-3 (negative misfit, elastically soft inclusions) studied by Pollock. The Eshelby energy calculations correctly predict the precipitate morphologies observed by Miyazaki et al. and by Pollock.
18
Yu, Yingyan, Zhiyuan Qu, Jiansheng Zhang, and Jie Zhou. "Influence of Surfacing Fe-Based Alloy Layers on Wire Arc Additive Manufactured Ni-Based Superalloys Material on Its Microstructure and Wear Properties." Materials 15, no. 17 (August 31, 2022): 6020. http://dx.doi.org/10.3390/ma15176020.
Анотація:
Wire arc additively manufactured (WAAM) Ni-based materials have good properties but are costly and hard to cut, leading to difficulties in machining after welding and wasting the materials. To overcome these shortcomings, this work proposes a method of surfacing Fe-based alloy layers on WAAM Ni-based material. The effect of this method on the microstructure and wear properties of WAAM Ni-based materials is discussed. In this work, a Fe-based alloy (JX103) was welded as the last layers of the WAAM Ni-based superalloy (JX201) material. The hardness, microstructure, and wear behavior of the material with different residual Fe-based materials were tested and analyzed. Our results indicate that the surface hardness was smoothly increased from HV350 to HV400 by overlaying Fe-based alloy layers. Microstructure analysis shows that γ-Fe gradually disappears, and the carbide form changes from WAAM Ni-based superalloys to Fe-based alloys. In the fusion boundary, the occurrence of cellular dendritic growth, a type -Ⅱ boundary, and low dilution indicate good crack resistance and good connection performance between these two materials. The wear test showed that the wear resistance of JX201 was decreased by changing the last layer to JX103. However, as the residual thickness of JX103 decreased, the influence gradually reduced. Meanwhile, the wear mechanism changed from severe abrasive and adhesive wear to light abrasive wear. When the thickness is less than 0.5 mm, the wear weight per minute is at the same level as the sample without JX103.
19
Anil, Semih Ekrem, Hasan Demirtas, Adnan Kalayci, and Abdulkadir Cebi. "Investigation of the Layer Effects Formed by W-EDM on Electrochemical Grooving of Stellite 21." Machines 11, no. 8 (August 10, 2023): 823. http://dx.doi.org/10.3390/machines11080823.
Анотація:
Machining hard-to-cut materials, such as cobalt (Co)-based superalloys, is a common problem in manufacturing industries. Background: wire electrical discharge machining (W-EDM) is one of the widely used cutting processes that causes layer (white layer—WL and heat-affected zone—HAZ) formation, and microcracks on the material’s surface. Purpose: this study investigates the effects of WL and HAZ on the electrochemical grooving (EC grooving) performance of Co-based superalloys. Two different surface types (W-EDMed and VFed) were used in the experiments. Result: the experiments showed that material removal rate (MRR) values increased up to 212.49% and 122.23% for vibratory finished (VFed) and wire-electrical-discharge-machined (W-EDMed) surfaces, respectively. Conclusion: This result indicates the presence of HAZ and WL that prevent current transition between two electrodes. However, increased voltage causes an increase in surface roughness, with increment rates at 71.13% and 36.08% for VFed and W-EDMed surfaces, respectively. Moreover, for the VFed surfaces, the groove lost its flatness at the bottom after an approximately 100 µm depth due to the different electrochemical machineabilities of HAZ and real surface texture. This result can be attributed to the different microstructures (HAZ and surface texture) showing different electrochemical dissolution rates. Therefore, high-depth distance HAZ and WL must be removed from the workpiece.
20
Tuominen, J., M. Hallaji, J. Kiviö, and J. Vihinen. "High-speed laser cladding: new developments for wear and corrosion protection." IOP Conference Series: Materials Science and Engineering 1296, no. 1 (December 1, 2023): 012037. http://dx.doi.org/10.1088/1757-899x/1296/1/012037.
Анотація:
Abstract Fusion-bonded and low-diluted overlay welded coatings are frequently very thick (>1mm), which results in high material consumption (kg/m2) and expenses. High-speed laser cladding is a novel process, which can produce thin fusion-bonded and low-diluted coatings with high coverage rates and low heat input. Coating materials utilized in high-speed cladding have varied from soft Ni-based superalloys to harder martensitic stainless steels and base materials from low alloy steels to austenitic stainless steels. The ultimate objective has been to develop crack-free alternatives to environmentally hazardous hard-chrome plating. In this paper, high-speed laser cladding was used to fabricate relatively thin Ni-based coatings on various cast irons for corrosion protection and Ni-based hard-faced coatings reinforced with chromium (Cr3C2) and tungsten carbides (WC/W2C), for the first time, onto low-alloy structural and quenched & tempered steels for wear applications. Obtained coatings were characterized with X-ray diffraction (XRD), optical (OM), and scanning electron microscopy (SEM). Corrosion performances were explored in long-term salt spray tests. Mechanical and wear properties were tested with Vickers microhardness measurements and three-body dry-sand rubber wheel abrasion tests (RWAT). It was shown that soft low-diluted Ni-based coatings protected the cast iron base materials in salt spray tests. Ni-based hard-faced coatings with hardness up to 1200 HV1 exhibited high wear resistance in low-stress three-body abrasion better than hard-chrome plated coating, which was attributed to the high volume fraction of hard carbide reinforcements.
21
Pickard, Andrew C., and David E. Mills. "Modeling of subsurface ceramic inclusions in metallic matrices." Journal of Strain Analysis for Engineering Design 55, no. 5-6 (March 19, 2020): 134–44. http://dx.doi.org/10.1177/0309324720910935.
Анотація:
All engineering materials have the potential to contain inhomogeneities that can act as initiators for fatigue cracks during cyclic loading. One class of inhomogeneity that can occur as a result of the processes used to create metallic materials is a ceramic inclusion, typically resulting from the raw material contamination during the melting process. This article examines the predicted behavior of hard ceramic inclusions in a nickel-base superalloy metallic matrix. Compressive residual stresses are created in the inclusion during cool down from a stress-free state at high temperature. The influence of the proximity of the inclusion to the surface of the matrix material is examined, together with the impact of subsequent uniaxial loading on the stress field in the inclusion and in the surrounding material. The stress field in the ceramic inclusion is observed to transition from compressive to tensile as a function of the proximity of the inclusion to the surface of the material and the applied uniaxial stress field. For deep subsurface inclusions, the uniaxial stress field required to achieve a tensile stress in the inclusion is close to the yield stress of the material. The sensitivity of this critical stress to material cyclic hardening behavior and to the temperature difference between the stress-free state and the operating state is also explored. The significance of these modeling results is discussed in terms of the sensitivity of nickel-base superalloys to crack formation and growth from ceramic inclusions and hence the impact on probabilistic fatigue life assessments of the presence, location and size of the ceramic inclusions.
22
Fedelich, B. "Modelling at the dislocation level the reinforcement of alloys by hard precipitates: The example of Ni-base superalloys." Journal de Physique IV (Proceedings) 105 (March 2003): 131–38. http://dx.doi.org/10.1051/jp4:20030180.
23
Kwiatkowski, Michał, Krzysztof Zaba, Maciej Nowosielski, Danel Pociecha, Tomasz Tokarski, and Paweł Kita. "Temperature Measurement in the Rotary Forming Process of a Nickel Superalloys (INCONEL) Sheet during Induction Heating." Key Engineering Materials 622-623 (September 2014): 823–30. http://dx.doi.org/10.4028/www.scientific.net/kem.622-623.823.
Анотація:
The processes of spinning and flow forming of hard metal sheets made from nickel superalloy INCONEL can be realized cold or with heating - e.g. by a induction or laser. When metal sheet is heated it is necessary to measure the temperature field on heated area, because its determines the deformation susceptibility. To control the temperature field pyrometers and infrared cameras are used. Due to strong changes in the surface of a formed material, under temperature influence (oxidation) and the action of the forming rolls, it is necessary to determine the emissivity coefficient values as a function of temperature and surface conditions. The paper presents the concept of determining these values, as well as an alternative technique for measuring temperature field, based on the methods of image analysis.
24
Pauzi, Ahmad Afiq, Mariyam Jameelah Ghazali, Wan Fathul Hakim W. Zamri, and Armin Rajabi. "Wear Characteristics of Superalloy and Hardface Coatings in Gas Turbine Applications–A Review." Metals 10, no. 9 (September 1, 2020): 1171. http://dx.doi.org/10.3390/met10091171.
Анотація:
In the gas-turbine research field, superalloys are some of the most widely used materials as they offer excellent strength, particularly at extreme temperatures. Vital components such as combustion liners, transition pieces, blades, and vanes, which are often severely affected by wear, have been identified. These critical components are exposed to very high temperatures (ranging from 570 to 1300 °C) in hot-gas-path systems and are generally subjected to heavy repair processes for maintenance works. Major degradation such as abrasive wear and fretting fatigue wear are predominant mechanisms in combustion liners and transition pieces during start–stop or peaking operation, resulting in high cost if inadequately protected. Another type of wear-like erosion is also prominent in turbine blades and vanes. Nimonic 263, Hastelloy X, and GTD 111 are examples of superalloys used in the gas-turbine industry. This review covers the development of hardface coatings used to protect the surfaces of components from wear and erosion. The application of hardface coatings helps reduce friction and wear, which can increase the lifespan of materials. Moreover, chromium carbide and Stellite 6 hardface coatings are widely used for hot-section components in gas turbines because they offer excellent resistance against wear and erosion. The effectiveness of these coatings to mitigate wear and increase the performance is further investigated. We also discuss in detail the current developments in combining these coating with other hard particles to improve wear resistance. The principles of this coating development can be extended to other high-temperature applications in the power-generation industry.
25
Cadoni, Ezio, Daniele Forni, Federico Mazzucato, and Anna Valente. "Tensile behaviour of Inconel 718 alloys under extreme conditions of temperature and strain-rate." EPJ Web of Conferences 250 (2021): 05010. http://dx.doi.org/10.1051/epjconf/202125005010.
Анотація:
Nickel-based superalloys are widely used in critical applications where structural components are subjected to harsh operating conditions such as elevated temperatures and high strain-rate. These alloys are also among the most hard-to-cut materials. For this reason, some critical components with complex geometrical features along with critical dimensions cannot easily manufactured by conventional technologies. A rising disruptive Additive Manufacturing (AM) technique, namely powder-based Laser Metal Deposition (LMD), is able to overcome these limitations in terms of manufacturing costs, tool wear, as well as lead time. As a consequence, the mechanical response under harsh condition of additively manufactured Nickel-based superalloys has to be accurately understood in order to guarantee the reliability of the structural parts made with them. Presently very few researches were addressed to study the dynamic tensile behaviour of Inconel 718 produced by additive manufacturing under high strain-rate combined with elevated temperature. To overcome this lack, the coupled effect of strain rate (0.001 s−1, 250 s−1 and 800 s−1) and temperature (20°C, 350°C and 550°C) on the tensile properties of Inconel 718 alloys produced through cast and additive manufacturing technologies has been experimentally studied. The experiments were also addressed to investigate and compare the flow stress behaviour in function of strain rate and temperature considering the differences in terms of microstructure. A modest strain-rate sensitivity has been observed for both as-cast and as-built material, as well as a moderate decrease of the mechanical strengths has been highlighted for increasing temperatures. Finally, comparable mechanical behaviour has been observed between additively manufactured samples produced with a power laser of 400W and as-cast samples.
26
Gama, Renann Pereira, and Marcos Valério Ribeiro. "Effects of Cutting Fluid Application in the Performance of the Nimomic 80A Turning." Key Engineering Materials 656-657 (July 2015): 243–50. http://dx.doi.org/10.4028/www.scientific.net/kem.656-657.243.
Анотація:
The increase of world requirements for improved products joined to growing competition between companies in the global market makes the same seek processes that ensure lower costs allied to high productivity and high quality product. Therefore, the great industrial and technological development has been increased the search for machining processes that promote, for example, high performance as regards the chip removal, less tool wear, failure and reduced impact on the environment. Regarding nickel-based superalloys, they have an extremely important role in the aeronautical and automotive industries among others. The nickel-based superalloy studied is the Nimonic 80A, hard machine material that has high mechanical strength and corrosion resistance on higher temperatures. The objective of this report is to study the influence of the application of cutting fluids in turning and the machining parameters in order to achieve high performance and optimization of machining this alloy. This one was machined using various machining parameters: cutting speed, feed rate, cutting depth, Minimum Quantity fluid (MQF), and Fluid abundant. After turning chip samples were obtained, was measured the surface roughness, volume of chip removed, cutting length and macro structural, some analyzes were performed and of lifetime of the tools were used in order to detect possible wear, as well as, microstructural observation of the chips by optical microscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS).On this report, we can observe the behavior of the materials and tools in the two cooling conditions used, and also, the impacts of the parameter variations in the surface finish, on the structure of the material and performance of the tools in respect chip removal regarding volume removed and machined length. Application by MQF was promising, but there is an abundant beyond the traditional application.
27
Safie, Syahilia Syahira, Muhamad Nasir Murad, and Tan Chye Lih. "Performance of Castor Oil and Neem Oil as Metal Cutting Fluids in Drilling Inconel 718 Using MQL Technique on Tool Wear and Surface Roughness." Journal of Physics: Conference Series 2129, no. 1 (December 1, 2021): 012070. http://dx.doi.org/10.1088/1742-6596/2129/1/012070.
Анотація:
Abstract Inconel 718 is hard to cut material due to its high hardness, high strength at elevated temperatures, low thermal diffusivity and affinity to react with tool materials. The high temperature during machining results in aggressive tool wear and poor hole quality. Therefore, the application of metal cutting fluids (MCF) as a lubricating and cooling agent is very significant in the drilling of nickel-based superalloys such as Inconel 718. The present study embraces these issues by evaluating the performance of non-edible vegetable oils such as castor and neem oil under minimal quantity lubrication (MQL) conditions towards the tool wear and surface roughness. The drilling experiments were carried out using coated (TiAlN) carbide drill with diameter of 6 mm at different cutting speeds of 10 and 20 m/min and a constant feed of 0.015 mm/rev. The results of this study showed that castor oil significantly outperformed the neem oil in drilling performance regarding tool wear and surface roughness.
28
Blum, Wolfgang. "Role of Boundaries in Control of Deformation Rate and Strength of Crystalline Materials." Materials Science Forum 604-605 (October 2008): 391–401. http://dx.doi.org/10.4028/www.scientific.net/msf.604-605.391.
Анотація:
Plastic deformation of crystalline materials is not controlled by interaction among free dislocations only, but the interaction of free dislocations with internal boundaries. i) Low-angle boundaries: Modeling of deformation of pure materials with conventional grain size on the basis of structure evolution indicates that low-angle boundaries act as obstacles of free dislocations. The migration of the low-angle boundaries constitutes an essential recovery process determining the deformation resistance in the steady state. ii) High-angle boundaries: Severe plastic deformation transforms low-angle boundaries into high-angle ones. They differ in obstacle and recovery characteristics from low-angle boundaries, which explains the special properties of ultrafine-grained and nanocrystalline materials with regard to strength, strain rate sensitivity and ductility. iii) Phase boundaries in Ni-base superalloys enhance the strengthening by hard phases with strengthening by dense dislocation networks serving to reduce coherency stresses. It is concluded that internal boundaries play a crucial role in controlling the evolution of structure and strength in crystalline materials.
29
Wallace Head, W. "A review of: “SUPERALLOYS, SUPERCOMPOSITES AND SUPERCERAMICS”edited by J.K. Tien and T. Caulfield Academic Press Inc. 755 pages, hard cover, 1989." Materials and Manufacturing Processes 5, no. 4 (January 1990): 663–65. http://dx.doi.org/10.1080/10426919008953284.
30
Gadenin, M. M. "Computation and experimental analysis of the resistance of superalloys to low cycle deformations." Industrial laboratory. Diagnostics of materials 88, no. 9 (September 21, 2022): 61–68. http://dx.doi.org/10.26896/1028-6861-2022-88-9-61-68.
Анотація:
Diagrams of cyclic elastoplastic deformation in a general case characterize the resistance of a material to a low cycle loading and display a relation between current values of stresses and strains during deformation process. Those diagrams in the mechanics of deformation and fracture are described by rather complicated state equations with a nonlinear dependence on conditions and modes of loading including temperature, deformation rate, cycle form, type of the stress state, absolute size of sections, working medium, type of constructional material, etc. The entity of aforementioned factors affects a shape of the deformation curve (diagram) of the material and key parameters of the corresponding state equations, including basic characteristics of the mechanical properties, i.e., the elasticity module, yield point and ultimate stress, indicators of static and cyclic hardening. Experimental data on the kinetics of cyclic and one-way accumulated plastic strains in each loading half-cycle (cycle) obtained in static and low cycle tests of nickel superalloy specimens revealed that change in deformation characteristics exhibit a drastically nonlinear character in conditions of cyclic elastoplastic strain which is described on the basis of power equations and corresponding parameters of cyclic deformation diagrams. The parameters of those equations depend on the type of cyclically hardening/softening or stable material under deformation of the material in elastoplastic region. It is noted that resistance of materials to cyclic elastic-plastic strain can be described by a set of analytical expressions containing a kinetic function (which changes with number of loading half-cycles) in the form of power or exponential expressions depending on the cyclic properties and characteristics of the mechanical properties of the specific structural material. The obtained calculated and experimental data on the kinetics of strain of the alloy under study in conditions of cyclic elastoplastic loading, as well as on the parameters of the strain diagram (which are basic characteristics for the corresponding state equations) provide the possibility to take full advantage of using the deformation-kinetic criteria of damage accumulation under considered loading conditions to calculate the fatigue life of the structural elements manufactured from the alloy and operated, as a rule, under severe temperature and heavy-loaded conditions. The results of the experiments and calculations are given in the form of diagrams of cycle-by-cycle kinetics of the cyclic and accumulated plastic strains of the material for the soft and hard modes of loading in a wide range of test temperatures.
31
Nakamura, Morihiko. "Fundamental Properties of Intermetallic Compounds." MRS Bulletin 20, no. 8 (August 1995): 33–39. http://dx.doi.org/10.1557/s0883769400045085.
Анотація:
More than 25 years have passed since Intermetallic Compounds, edited by Westbrook, was published. Since that time, enormous advances have been made in the understanding and usage of intermetallic compounds. It is known that intermetallic compounds are generally brittle. Thus, alloys that contain intermetallics may also be brittle. However, many intermetallic compounds are known to have extraordinary functions and characteristics that are not observed in ordinary metals and alloys. Thus, they function as magnetic materials, superconductors, semiconductors, hydrogen absorbing alloys, shape memory alloys, and so on.Many high-strength structural alloys like maraging steels and duralumins are strengthened by fine precipitates of intermetallic phases. Nickel-based superalloys, which are used for airplane-engine parts, contain 60-70% of Ni3Al-based intermetallics by volume fraction and exhibit high strength at high temperatures. Hard metals, which are used for cutting tools, are composed of a large amount of hard but brittle intermetallics like WC and a small amount of ductile cobalt. Intermetallic compounds like TiAl are also investigated for their applications as structural materials where high strength at high temperatures is required.In a strict sense, intermetallic compounds are composed of two or more metallic elements. In a wider sense, they are composed of metallic and/or semimetallic elements. Each is characterized by an ordered arrangement of two or more kinds of atoms, that is, the formation of a superlattice, and have various kinds of interatomic bonding, ranging from metallic to covalent or ionic bonding. The ordering of atoms and the strong interatomic bonding result in many attractive properties for intermetallic compounds.
32
Singh, Gurpreet, Vivek Aggarwal, Sehijpal Singh, Rajiv Kumar Garg, and Balkar Singh. "Experimental and Analytical Investigation into Cutting Forces during Turning of EN-31 Steel in Different Machining Conditions." Key Engineering Materials 933 (October 17, 2022): 42–61. http://dx.doi.org/10.4028/p-d72alb.
Анотація:
Metal cutting is the way of processing the workpiece with tool having sharp cutting edges of different materials generating chips of different shapes and sizes. In present era of industry 4.0, metal machining should not be unrated during processing of hard grades metals and superalloys where large amount of cutting forces are generated. Also, the measurement of cutting forces provides the basic of economical machining and hence accurate evaluation in experimental and analytical manner has great importance. The traditional models of metal cutting have disagreement with experimental results due to missing of important mechanics terms. With the development of digital technology, the errors in calculation of cutting force have also been shortened due to consideration of terms absent in conventional models. In present investigation, the cutting forces have been evaluated experimentally using dynamometer and analytically with Astakhov’s methodology during turning of EN-31 steel. The results revealed that 12.9% observations have deviation more than 20%, whereas 16.67 % has zero deviation. Further, the feed rate has more influence on cutting forces as compared to speed and nose radius. In addition, the minimum quantity lubrication (MQL) of vegetable oil has lowered the cutting forces appreciably compared to dry machining.
33
Rinck, Philipp M., Alpcan Gueray, and Michael F. Zaeh. "Modeling of cutting forces in 1-D and 2-D ultrasonic vibration-assisted milling of Ti-6Al-4V." International Journal of Advanced Manufacturing Technology 119, no. 3-4 (November 30, 2021): 1807–19. http://dx.doi.org/10.1007/s00170-021-08355-x.
Анотація:
AbstractTo meet the modern demands for lightweight construction and energy efficiency, hard-to-machine materials such as ceramics, superalloys, and fiber-reinforced plastics are being used progressively. These materials can only be machined with great effort using conventional machining processes due to the high cutting forces, poor surface qualities, and the associated tool wear. Vibration-assisted machining has already proven to be an adequate solution in order to achieve extended tool lives, better surface qualities, and reduced cutting forces. This paper presents an analytical force model for longitudinal-torsional vibration-assisted milling (LT-VAM), which can predict cutting forces under intermittent and non-intermittent cutting conditions. Under intermittent cutting conditions, the relative contact ratio between the rake face and the sliding chip is utilized for modelling the shearing forces. Ploughing forces and shearing forces under non-intermittent cutting conditions are calculated by using an extended macroscopic friction reduction model, which can predict the reduced frictional forces under parallel and perpendicular vibration superimposition. The force model was implemented in MATLAB and can predict cutting forces without using any experimental vibration-assisted milling (VAM) data input.
34
Palanisamy, Duraiswamy, P. Thejasree, Umapathi Durai, and Natarajan Manikandan. "A Study on the Machinability of Wire Electrical Discharge Machining of Nickel Alloy Using Taguchi Grey Approach." Key Engineering Materials 971 (December 20, 2023): 33–43. http://dx.doi.org/10.4028/p-2zae5p.
Анотація:
Superalloys, referred to as nickel alloys, have several uses in engineering and are widely used in industries that are as diverse as chemical processing and food processing. The high thermal conductivity and high strength of these materials make them hard to remove material from with traditional processing techniques. The majority of modern techniques for machining harder materials are alternatives to older methods. The present study is focusing on Wire Electrical Discharge Machining (WEDM), a modern machining technique used for the processing of tougher materials. The aspiration of this work is to present a Taguchi-based Grey technique that can be used to optimize a number of different performance indicators. The connection between the input and output variables has been analyzed using a regression model. Taguchi's design approach has been applied to the design of trials, with the Pulse on/off time and the applied current serving as independent variables. For enhancing the multiple machining performance of nickel alloy during Wire Electrical Discharge Machining (WEDM), this experimental effort seeks to pinpoint the most effective variables. This is accomplished using the Taguchi-Grey method. The performance analysis offers producers with concrete proof of the efficiency of evolved systems, allowing them to make well-informed and effective choices.
35
Kihara, Eliane Alves, Henara Lillian Costa, and Demostenes Ferreira Filho. "Effect of the Shielding Gas and Heat Treatment in Inconel 625 Coatings Deposited by GMAW Process." Coatings 14, no. 4 (March 28, 2024): 396. http://dx.doi.org/10.3390/coatings14040396.
Анотація:
Friction, wear, and corrosion of engineering components operating in harsh environments can be substantially improved by applying hard, corrosion-resistant coatings to prolong their useful lives. Nickel superalloys are particularly relevant due to their excellent mechanical properties and corrosion resistance at elevated temperatures. Among the various coating techniques, arc welding processes are suitable due to their good deposition rate and reliability. This work aimed to evaluate the effect of the shielding gas and after-deposition heat treatment on the microstructure and mechanical properties of Inconel 625 coatings deposited by the GMAW process. The coatings were deposited onto carbon steel plates using two mixtures of shielding gases (Ar+25%CO2 and Ar+25%He) without interpass temperature control. The specimens were analyzed both as welded and after heat treatment (heating for 1 h at 1000 °C and air cooling) using Vickers hardness tests, scanning electron microscopy, energy-dispersive X-ray spectroscopy (EDS), and wavelength dispersion spectrometry (WDS). The coatings that used Ar+25%He-shielding gas were harder and showed more precipitate formation, which was associated with the higher cooling rates involved. As for the heat treatment, it led to a reduction in the segregation of the alloying elements in the interdendritic region via diffusion and a reduction in surface hardness.
36
Nadolny, Krzysztof, Walery Sienicki, and Michał Wojtewicz. "The effect of sulfurization on the grinding wheel cutting ability in the internal cylindrical grinding of nickel superalloys." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 231, no. 1 (August 8, 2016): 140–54. http://dx.doi.org/10.1177/0954405415572643.
Анотація:
One possible way of preventing excessive growth of smearings/loads on the grinding wheel active surface is the introduction of compounds such as sulfur, graphite, or wax into the grinding wheel volume which exerts an active influence on adhesion during the process of impregnation. Limiting the formation of smearings/loads on the grinding wheel active surface is of crucial importance to achieve effective grinding of hard-to-cut materials (such as nickel superalloys) which are characterized by considerable ductility and a strong chemical affinity to abrasive grains, among other things. This article presents the results of experimental tests performed on plunge grinding and the influence of sulfur impregnation of grinding wheels on the smearing/load intensity on the grinding wheel active surface during the process of internal cylindrical plunge grinding of openings made from Inconel® alloy 600 and Incoloy® alloy 800HT®. Bearing steel 100Cr6 was included in the tests as a reference material. Grinding wheels were impregnated with a new method of gravitational sulfurization combined with centrifuging. The experiments carried out show that the adhesive properties of sulfur allowed for considerable limitation of smearing/loading of the grinding wheel active surface with machined material. This mainly concerned limiting the formation of the largest and most technologically undesirable smearings/loads of the intergranular spaces. The presence of sulfur in the grinding wheel volume had a minor influence on the intensity of smearings/loads in the microareas of the active abrasive grains’ apexes. The tests also showed an increase of 32%–49% in the value of parameter Sa in the surfaces ground with grinding wheels impregnated with sulfur for all the examined materials.
37
Berthod, Patrice, Merzouk Bouaraba, and Junfu Cai. "Influence of the Chromium Content on the Characteristics of the Matrix, the Tantalum Carbides Population, and the Hardness of Cast Co(Cr)-0.4C-6Ta Alloys." Micro 3, no. 1 (February 16, 2023): 239–55. http://dx.doi.org/10.3390/micro3010017.
Анотація:
The mechanical and chemical behaviors of cast cobalt-base superalloys are governed by the carbides and by a reactive element, which is often chromium. The content of this later element, which is efficient in resisting hot oxidation and also hot corrosion, may have consequences on the melting temperature, microstructure, and mechanical properties at high temperatures and at room temperature. Seemingly, the effect of chromium content on the microstructure and properties of cast equi-axed Co-Cr-Ta-C superalloys containing TaC as single reinforcing carbide and in high-enough quantities to achieve a high level of creep resistance has not been the subject of previous investigations. The present work is devoted to the exploration of this influence of Cr content on the as-cast microstructure of a model alloy in this category, as well as on its microstructure transformations at high temperatures. The work aims to help rate the Cr content to achieve the best characteristics in machinability and high-temperature properties. This is of great importance for fabricability (production cost) and sustainability in service (long enough lifetime performance). A series of six alloys derived from a rather well-known alloy and presenting various Cr contents were thus elaborated by casting. Their microstructures were investigated in their as-cast state as well as in an aged state resulting from a 4-day stage at 1400 K. Vickers indentation was also carried out to study how hardness may evolve with Cr content. It was seen that the higher the Cr content, the lower the solidus temperature, the coarser the TaC population, the harder the alloy, and the higher the risk of brittleness. In order to reach the best compromise, the preferred Cr weight content range, as identified by this work, is 20–30%; indeed, for such Cr contents: (1) the matrix is austenitic, then dense, and then hard and not brittle, and thus is mechanically resistant and tough; (2) the TaC carbides are script-shaped and resistant against morphology changes at high temperatures, and thus efficiently preserve interdendritic cohesion for a long time, and, consequently, (3) the alloys are machinable, have expected good toughness, and can be resistant against creep deformation as well as oxidation and corrosion at high temperatures thanks to the Cr content, allowing for chromium-forming behavior.
38
Chen, Kuan-Jen, and Hung-Mao Lin. "Effects of Niobium Carbide Additions on Ni-Based Superalloys: A Study on Microstructures and Cutting-Wear Characteristics through Plasma-Transferred-Arc-Assisted Deposition." Coatings 14, no. 2 (January 28, 2024): 167. http://dx.doi.org/10.3390/coatings14020167.
Анотація:
This study applied plasma transferred arc (PTA) welding to fabricate hard cladding layers by using nickel-based superalloy (NCR7) and niobium carbide (NbC) powders as filler material. The resultant composite claddings were coated onto ductile iron and then analyzed to understand the effect of different quantities of NbC on the solidification structures of the cladding layers and on the characteristics of the interface between the cladding layers and the ductile iron. Cutting tests were also conducted to assess the morphology and mechanism of flank wear on PTA NbC/NCR7 composite cladding tools. The results revealed that the cladding specimens’ microstructures comprised a mixture of dendrites and interdendritic eutectics along with a considerable quantity of carbides (MC, M7C3, and M23C6) scattered within the γ-Ni matrix. Incorporating considerable NbC carbide enhanced the claddings’ surface hardness, but it had a limited effect on improving the flank wear on the turning tools. The flank wear on the composite cladding tools intensified as the NbC content was increased. The wear behavior, defined by brittle fractures and stripped NbC particles, led to a decline in turning tool performance. Accordingly, the Ni-based alloy composite cladding with larger NbC particles appears more suitable for sliding or erosion applications under normal stress conditions.
39
Sequeiros, Elsa W., Anibal Guedes, Ana Maria Pires Pinto, Manuel F. Vieira та Filomena Viana. "Microstructure and Strength of γ-TiAl Alloy/Inconel 718 Brazed Joints". Materials Science Forum 730-732 (листопад 2012): 835–40. http://dx.doi.org/10.4028/www.scientific.net/msf.730-732.835.
Анотація:
Intermetallics and superalloys brazing development is a current topic owing the extending use of these alloys in industrial applications. In this work a γ-TiAl alloy was joined to Inconel 718 by active metal brazing, using Incusil-ABA as filler. Joining was performed at 730 °C, 830 °C and 930 °C, with a 10 min dwelling time. The interfaces were characterized by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and Electron Backscatter Diffraction (EBSD). For all processing conditions, the reaction between the base materials and the braze alloy produced multilayered interfaces. For all processing temperatures tested (Ag), (Cu), AlNi2Ti and AlCu2Ti were identified at the interface. Raising the brazing temperature increased the thickness of the interface and coarsened its microstructure. The increase of the extension of the interface was essentially due to the growth of the reaction layers formed near each base material, which were found to be mainly composed of intermetallic compounds. The mechanical behavior of the joints, at room temperature, was assessed by microhardness and shear tests. For all processing conditions the hardness decreases from periphery towards the Ag-rich centre of the joints. Brazing at 730 °C for 10 min produced the joints with the highest average shear strength (228±83 MPa). SEM and EDS analysis of the fracture surfaces revealed that fracture of joints always occurred across the interface, preferentially through the hard layer, essentially composed of AlNi2Ti, resulting from the reaction between Inconel 718 and the braze alloy.
40
Ma, Ke, and Jinhai Wang. "Microstructural Characteristics and Mechanical Properties of an Additively Manufactured Nickel-Based Superalloy." Crystals 12, no. 10 (September 26, 2022): 1358. http://dx.doi.org/10.3390/cryst12101358.
Анотація:
The nickel-based superalloys processed by additive manufacturing are very promising structural materials in aircraft engines as high-pressure turbine discs. In this work, a nickel-based superalloy with good mechanical performance and few defects was manufactured by optimized selective laser melting (SLM) processing. We then investigated the influences of post heat treatments on its microstructural characteristics and mechanical performance. The results indicated that a fine grain size with uniform grain orientation was presented in the as-printed nickel-based superalloy sample. After heat treatments, the grains were slightly grown and grain orientation was also changed. Under transmission electron microscopy, fine subgrains with an approximate size of 0.5 μm were found in the as-printed sample which accompanied massive dislocations and discontinuous Laves phases. After the post heat treatments, fine subgrains and less dislocations were retained. On the other hand, massive γ′ and γ″ precipitates with an orientation relationship of (001)[100]γ′//(100)[001]γ or (001)[100]γ″//(100)[001]γ were formed. As a result, the yield stress and tensile strength increased to 1362 and 1410 MPa, respectively, in a heat-treated sample, which retained the identical elongation of the as-printed specimen.
41
Kapłonek, Wojciech, Krzysztof Nadolny, Krzysztof Rokosz, Jocelyne Marciano, Mozammel Mia, Danil Yurievich Pimenov, Olga Kulik, and Munish Kumar Gupta. "Internal Cylindrical Grinding Process of INCONEL® Alloy 600 Using Grinding Wheels with Sol–Gel Alumina and a Synthetic Organosilicon Polymer-Based Impregnate." Micromachines 11, no. 2 (January 21, 2020): 115. http://dx.doi.org/10.3390/mi11020115.
Анотація:
The development of modern jet engines would not be possible without dynamically developed nickel–chromium-based superalloys, such as INCONEL® The effective abrasive machining of above materials brings with it many problems and challenges, such as intensive clogging of the grinding wheel active surface (GWAS). This extremely unfavorable effect causes a reduction in the cutting ability of the abrasive tool as well as increase to grinding forces and friction in the whole process. The authors of this work demonstrate that introduction of a synthetic organosilicon polymer-based impregnating substance to the GWAS can significantly improve the effects of carrying out the abrasive process of hard-to-cut materials. Experimental studies were carried out on a set of a silicon-treated small-sized sol–gel alumina 1-35×10×10-SG/F46G10VTO grinding wheels. The set contained abrasive tools after the internal cylindrical grinding process of INCONEL® alloy 600 rings and reference abrasive tools. The condition of the GWAS after the impregnation process was studied, including imaging and measurements of its microgeometry using confocal laser scanning microscopy (CLSM), microanalysis of its elemental distribution using energy dispersive X-ray fluorescence (EDXRF), and the influence of impregnation process on the grinding temperature using infrared thermography (IRT). The obtained results confirmed the correctness of introduction of the impregnating substance into the grinding wheel structure, and it was possible to obtain an abrasive tool with a recommended characteristic. The main favorable features of treated grinding wheel concerning the reduction of adhesion between the GWAS and grinding process products (limitation of the clogging phenomenon) as well as reduction of friction in the grinding process, which has a positive effect on the thermal conditions in the grinding zone.
42
Syed, Hasan Sohail, Abba Abdulhamid Abubakar та Abbas Saeed Hakeem. "A Material-by-Design Approach to Develop Ceramic- and Metallic-Particle-Reinforced Ca-α-SiAlON Composites for Improved Thermal and Structural Properties". Nanomaterials 12, № 13 (24 червня 2022): 2176. http://dx.doi.org/10.3390/nano12132176.
Анотація:
α-SiAlON is commonly used to machine superalloys owing to its desirable thermal and structural properties. α-SiAlON is among the crystalline forms of SiAlON and has more favorable properties than β-SiAlON. However, it becomes fragile during the machining of hard-to-cut materials due to its low fracture toughness and machinability. Recent research efforts focus on improving the thermal and structural properties of α-SiAlON using suitable dopants, nano-sized precursors, and the addition of metallic/ceramic reinforcement particles. The present study presents a material-by-design approach to designing and developing ceramic and metal-particle-reinforced Ca-α-SiAlON composites with properties tailored for the cutting tool applications. The mean-field homogenization theories and effective medium approximations implemented in an in-house code are used to effectively optimize the thermal and structural properties of the Ca-α-SiAlON composite by varying essential parameters such as inclusion material, volume fraction, porosity, particulate size, and thermal interface resistance. Individual properties of the matrix and reinforcements are considered in the computations of effective properties such as thermal conductivity, thermal expansion coefficient, modulus of elasticity, and fracture toughness. The main objective of the study is to enhance the thermal conductivity and fracture toughness of Ca-α-SiAlON, while lowering its thermal expansion coefficient. At the same time, the elastic modulus and hardness/strength must be maintained within an acceptable range. As a validation, Ni/Ca-α-SiAlON and SiC/Ca-α-SiAlON composites are synthesized from the nano-sized precursors, CaO dopant, and Ni/SiC microparticles via spark plasma sintering (SPS) process. The thermal conductivity, coefficient of thermal expansion, and elastic modulus of the composites are measured and compared with the computational predictions. The computational predictions are found to be comparable to that of the experimental measurements. Moreover, the studies show that WC, SiC, and Cr can be suitable reinforcement materials for enhancing the thermal and structural properties of Ca-α-SiAlON material for the cutting tool inserts.
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Cep, Robert, Adam Janasek, Jana Petru, Lenka Cepova, Andrej Czan, and Jan Valicek. "Hard Machinable Machining of Cobalt-based Superalloy." Manufacturing Technology 13, no. 2 (June 1, 2013): 142–47. http://dx.doi.org/10.21062/ujep/x.2013/a/1213-2489/mt/13/2/142.
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Zhang, Chengcong, and Amir Shirzadi. "Fail-Safe Joints between Copper Alloy (C18150) and Nickel-Based Superalloy (GH4169) Made by Transient Liquid Phase (TLP) Bonding and Using Boron-Nickel (BNi-2) Interlayer." Metals 11, no. 10 (September 23, 2021): 1504. http://dx.doi.org/10.3390/met11101504.
Анотація:
Joining heat conducting alloys, such as copper and its alloys, to heat resistant nickel-based superalloys has vast applications in nuclear power plants (including future fusion reactors) and liquid propellant launch vehicles. On the other hand, fusion welding of most dissimilar alloys tends to be unsuccessful due to incompatibilities in their physical properties and melting points. Therefore, solid-state processes, such as diffusion bonding, explosive welding, and friction welding, are considered and commercially used to join various families of dissimilar materials. However, the solid-state diffusion bonding of copper alloys normally results in a substantial deformation of the alloy under the applied bonding load. Therefore, transient liquid phase (TLP) bonding, which requires minimal bonding pressure, was considered to join copper alloy (C18150) to a nickel-based superalloy (GH4169) in this work. BNi-2 foil was used as an interlayer, and the optimum bonding time (keeping the bonding temperature constant as 1030 °C) was determined based on microstructural examinations by optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), tensile testing, and nano-hardness measurements. TLP bonding at 1030 °C for 90 min resulted in isothermal solidification, hence obtained joints free from eutectic phases. All of the tensile-tested samples failed within the copper alloy and away from their joints. The hardness distribution across the bond zone was also studied.
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Razumovskiy, Vsevolod I., A. Y. Lozovoi, Igor M. Razumovskii, and Andrei V. Ruban. "Analysis of the Alloying System in Ni-Base Superalloys Based on Ab Initio Study of Impurity Segregation to Ni Grain Boundary." Advanced Materials Research 278 (July 2011): 192–97. http://dx.doi.org/10.4028/www.scientific.net/amr.278.192.
Анотація:
A new approach to the design of Ni-based polycrystalline superalloys is proposed. It is based on a concept that under given structural conditions, the performance of superalloys is determined by the strength of interatomic bonding both in the bulk and at grain boundaries of material. We characterize the former by the cohesive energy of the bulk alloy, whereas for the latter we employ the work of separation of a representative high angle grain boundary. On the basis of our first principle calculations we suggest Hf and Zr as “minor alloying additions” to Ni-based alloys. Re, on the other hand, appears to be of little importance in polycrystalline alloys.
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Li, Ye, and Chun Bin Cai. "Finite Element Analysis of High Temperature Alloy Cutting Process Based on Abaqus." Key Engineering Materials 667 (October 2015): 237–43. http://dx.doi.org/10.4028/www.scientific.net/kem.667.237.
Анотація:
The nickel-based superalloy GH4169 is widely used in the aerospace industry because of its excellent comprehensive mechanical properties under high temperature and corrosion condition. It is one of the most difficult-to-machine materials due to low thermal conductivity and hard particle. One method of solving the problem of maching difficult-to machine materials is using new material cutting tool. PCBN tool has excellent cutting property in maching nickel-based superalloy because of its great hardness, high wear resistance and good chemical stability. The cutting process of in-depth study of PCBN tool cutting nickel-based superalloy, shows the variation rule of cutting force and cutting temperature, can provide a theoretical basis for process specification high temperature alloy and efficient processing, has a very big practical significance. On the basis of reasonable hypothesis, this paper discusses in detail the transformation from actual turning to 2D orthogonal free cutting geometry model. Based on this,through the establishment of simulation model of PCBN turning the nickel-based superalloy GH4169, studying on the tool rake angle γo, back angle αo, cutting speedvcand feedfon cutting process of cutting force and cutting temperature effect.
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Song, Jeonyoung, Jiho Gu, Jiho Gu, Won Hui Jo, Cho Hyeon Lee, Jae Bok Seol та Youngwha Ma. "Effect of Heat Treatment Temperature on Microstructure, Tensile Properties and δ-Precipitate Phase in Ni-based Superalloy". Korean Journal of Metals and Materials 62, № 1 (5 січня 2024): 32–38. http://dx.doi.org/10.3365/kjmm.2024.62.1.32.
Анотація:
Here, we investigated the influence of δ-precipitate (orthorhombic D0a Ni<sub>3</sub>Nb-ordered phase) on the room- and high-temperature tensile properties in wrought nickel-based Inconel 625 superalloys subjected to solution and aging heat treatment. Typically, solution heat-treatment temperatures in these alloys affect the solid-state precipitation of δ-phase, which governs high-temperature tensile properties. While precipitation of fine D0<sub>a</sub> δ-phase is known to have beneficial effects on the mechanical properties owing to the retardation of grain coarsening, Widmanstätten δ precipitation plays a deleterious influence on the fracture toughness, tensile ductility, and fatigue resistance. Therefore, to enhance the mechanical properties of this alloy series, it is key to generate a high number density of fine D0<sub>a</sub> δ precipitate by adjusting solid solution treatment temperatures. In this study, solution heat treatments were conducted above and below δ-phase solvus temperatures. By applying solution heat treatment at 900°C and 970°C, this alloy was confirmed to have a Widmanstätten δ phase and is composed similarly to the annealed microstructure. This Widmanstätten δ precipitate was densely distributed at both intergranular and intragranular grains. On the other hand, when solution treatment was applied at 1040 and 1100°C, more coarse particles (approximately 30 μm) with a significant reduction of Widmanstätten type δ phase were obtained. We found that grain size and Widmanstätten δ-phases have an important role in the high-temperature tensile properties of Inconel 625 superalloy series.
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Román-Sedano, Alfonso Monzamodeth, Bernardo Campillo, Julio C. Villalobos, Fermín Castillo, and Osvaldo Flores. "Hydrogen Diffusion in Nickel Superalloys: Electrochemical Permeation Study and Computational AI Predictive Modeling." Materials 16, no. 20 (October 10, 2023): 6622. http://dx.doi.org/10.3390/ma16206622.
Анотація:
Ni-based superalloys are materials utilized in high-performance services that demand excellent corrosion resistance and mechanical properties. Its usages can include fuel storage, gas turbines, petrochemistry, and nuclear reactor components, among others. On the other hand, hydrogen (H), in contact with metallic materials, can cause a phenomenon known as hydrogen embrittlement (HE), and its study related to the superalloys is fundamental. This is related to the analysis of the solubility, diffusivity, and permeability of H and its interaction with the bulk, second-phase particles, grain boundaries, precipitates, and dislocation networks. The aim of this work was mainly to study the effect of chromium (Cr) content on H diffusivity in Ni-based superalloys; additionally, the development of predictive models using artificial intelligence. For this purpose, the permeability test was employed based on the double cell experiment proposed by Devanathan–Stachurski, obtaining the effective diffusion coefficient (Deff), steady-state flux (Jss), and the trap density (NT) for the commercial and experimentally designed and manufactured Ni-based superalloys. The material was characterized with energy-dispersed X-ray spectroscopy (EDS), atomic absorption, CHNS/O chemical analysis, X-ray diffraction (XRD), brightfield optical microscopy (OM), and scanning electron microscopy (SEM). On the other hand, predictive models were developed employing artificial neural networks (ANNs) using experimental results as a database. Furthermore, the relative importance of the main parameters related to the H diffusion was calculated. The Deff, Jss, and NT achieved showed relatively higher values considering those reported for Ni alloys and were found in the following orders of magnitude: [1 × 10−8, 1 × 10−11 m2/s], [1 × 10−5, 9 × 10−7 mol/cm2s], and [7 × 1025 traps/m3], respectively. Regarding the predictive models, linear correlation coefficients of 0.96 and 0.80 were reached, corresponding to the Deff and Jss. Due to the results obtained, it was suitable to dismiss the effect of Cr in solid solution on the H diffusion. Finally, the predictive models developed can be considered for the estimation of Deff and Jss as functions of the characterized features.
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Jiang, Wenxiang, Xiaoyi Ren, Jinghao Zhao, Jianli Zhou, Jinyao Ma, Wenjing Zhang, Yuefei Zhang, and Ze Zhang. "Crack Propagation Behavior of a Ni-Based Single-Crystal Superalloy during In Situ SEM Tensile Test at 1000 °C." Crystals 10, no. 11 (November 17, 2020): 1047. http://dx.doi.org/10.3390/cryst10111047.
Анотація:
An in situ scanning electron microscope (SEM) tensile test for Ni-based single-crystal superalloy was carried out at 1000 °C. The stress displacement was obtained, and the yield strength and tensile strength of the superalloy were 699 MPa and 826 MPa, respectively. The crack propagation process, consisting of Model I crack and crystallographic shearing crack, was determined. More interestingly, the crack propagation path and rate affected by eutectics was directly observed and counted. Results show that the coalescence of the primary crack and second microcrack at the interface of a γ/γ′ matrix and eutectics would make the crack propagation rate increase from 0.3 μm/s to 0.4 μm/s. On the other hand, crack deflection decreased the rate to 0.05 μm/s. Moreover, movement of dislocations in front of the crack was also analyzed to explain the different crack propagation behavior in the superalloy.
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Birosca, S. "The deformation behaviour of hard and soft grains in RR1000 nickel-based superalloy." IOP Conference Series: Materials Science and Engineering 82 (April 24, 2015): 012033. http://dx.doi.org/10.1088/1757-899x/82/1/012033.