Journal articles on the topic 'Die castings'
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1
Zhengwuvi, L. B., and A. O. Akii Ibhadode. "Risering of a Four-Cavity Die Production Mould by Convectional Method." Advanced Materials Research 62-64 (February 2009): 664–70. http://dx.doi.org/10.4028/www.scientific.net/amr.62-64.664.
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This paper demonstrates the possibility of developing skill in producing sound metal casting from a four-cavity die production mould by assessing the riser design criteria and the castings. The assessment takes into account the location of the casting’s hot spots, casting modulus, liquid metal mass in the risers and the principle of directional solidification. The mould flask is oriented in such a way that a riser is placed directly on top of the casting’s hot spots for proper feeding during solidification. The assessment result of casting modulus shows that the feeder modulus Mf = 5.85 x 10-3 M and the casting hot spot modulus Mh = 1.88 x 10-3 M .The assessment result of castings solidification time shows that the castings solidify within 12 seconds while the feeders solidify within 30 seconds. From the assessment results it is observed that the risers hold liquid metal, feed the castings to full solidification and solidify later than the castings which they feed. Examinations at the cross sections of the finished castings revealed the absence of void formation which is a clear indication of effective and functional risers. Thus, the risers have achieved the desired requirement.
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Chaikin, A. V. "Theory and practice of inoculation for high-grade gray cast iron railway castin." Ferrous Metallurgy. Bulletin of Scientific , Technical and Economic Information 80, no. 5 (June 20, 2024): 37–44. http://dx.doi.org/10.32339/0135-5910-2024-5-37-44.
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JSC “Cheboksary Aggregate Plant” has mastered the production of high-strength gray cast iron "wedge friction" railway castings (grade SCH30) intended for freight wagon bogies. According to the casting's technical specifications, the presence of interdendritic graphite and cementite in the vertical and sloping walls of the casting is not allowed. However, in separate batches, interdendritic graphite and up to 10 % cementite were found in the controlled walls of the castings. To solve the problem of obtaining castings with a blemish-free microstructure, the iron modification technology was changed. Instead of ferrosilicon FS 75, a more effective composite dispersed inoculant was developed and implemented. The advantages of the latter, which consisted of chemically treated ultrafine modifier (USM) and a by-product of organosilane production (KSM), were theoretically substantiated. The advantages of the developed modifier over FS75 were confirmed by modeling the behavior of inoculant’s particles when filling the “wedge friction” cavities in the FLOW-3D program. USM and KSM particles were evenly distributed throughout the volume of the castings at all observed heights of the controlled casting walls. They served as graphite crystallization centers throughout the solidification time of the castings, ensuring the absence of blemishes in the castings. The introduction of the developed material into production allowed reducing the modifier consumption by 6.25 times, ensuring the absence of blemishes in the castings, achieving the required mechanical properties of the iron, and an economic effect of over 4 million rubles
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Kordas, P. "Influence of the conditions of casting and heat treatment on the structure and mechanical properties of the AlMg10 alloy." Journal of Achievements in Materials and Manufacturing Engineering 1, no. 83 (July 1, 2017): 26–32. http://dx.doi.org/10.5604/01.3001.0010.5137.
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Purpose: Assessment of the possibilities of shaping the structure and improvement of mechanical properties of casting from AlMg10 alloy through a selection of casting technology and precipitation hardening. Design/methodology/approach: the work evaluated the impact of casting and heat treatment technology on the mechanical properties and structure of AlMg10 alloy castings. The tests were performed on 200 mm × 100 mm × 25 mm plate castings produced by gravity casting methods for sand and metal moulds and by a liquid state press moulding technology. Castings made with these technologies solidify in substantially different heat- evaporation conditions and exhibit varying degrees of primary structure fragmentation. Metallographic and strength tests were performed on raw castings and after heat treatment. Findings: The changes in the morphology and size of primary crystals and the dispersion of the reinforcing phase according to the casting solidification rate and the precipitation hardening treatment were analyzed. Solidifying castings in the form of sand show a globular structure, whereas in die and press castings, a typically dendritic structure occurs, with the dendritic crystals in pressed castings being much smaller in size than the die castings. In castings which were not heat-treated, the reinforcing phase of Al3Mg2 occurs in interdendritic spaces, and its dispersion increases with the rate of cooling. After supersaturation and ageing treatments, the phase α has a grain structure in all samples. The largest dispersion of reinforcing molecules is characterized by press castings. In a raw state, the highest mechanical properties are shown by castings made in the form of sand and the method of pressing in a liquid state. Heat treatment of AlMg10 alloy castings significantly influences the increase of mechanical indexes in all castings investigated. The highest features of Rm are approx. 330 MPa and A5 above 10% is obtained in castings made by the press method. Research limitations/implications: Particular attention should be paid to the avoidance of the effects of slag inclusion, shrinkage and magnesium oxidation during casting of AlMg10 alloys. In die castings of a plate type, due to own stresses, a significant decrease in mechanical properties occurs. Practical implications: The most advantageous mechanical properties of AlMg10 alloy castings are obtained by using liquid-state pressing technology. In addition, this technology makes it possible to produce thin-walled castings of high dimensional accuracy, high air- tightness, fine grain structure, lack of surface defects and low roughness. Originality/value: The paper presents the possibility of improving the mechanical properties of AlMg10 castings by applying heat treatment. It has been proven that the casting method has a significant effect on the mechanical properties of the castings.
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Midson, Stephen. "Industrial Applications for Aluminum Semi-Solid Castings." Solid State Phenomena 217-218 (September 2014): 487–95. http://dx.doi.org/10.4028/www.scientific.net/ssp.217-218.487.
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The goal of this paper is to examine industrial applications for semi-solid castings, and to develop strategies necessary for the wider commercialization of the semi-solid casting process. The performance and production techniques of semi-solid castings are reviewed, with the goal of identifying commercial niches where semi-solid castings can provide clear benefits over other casting process. A comparison of mechanical properties between semi-solid castings and other casting processes is presented. In addition, this paper provides an evaluation of the features of the optimal semi-solid casting processes, examines the characteristics of components that would benefit for production by semi-solid casting and describe the types of quality systems that casters need to have in place to make these types of castings. Cost analyses are presented suggesting that rheocasting can complete well with other casting processes.
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Yu, Hai Liang, Jin Wu Kang, Shi Xiong Huang, and Tian You Huang. "Integrated Simulation of Castings Deformation during Casting and Heat Treatment Processes." Advanced Materials Research 148-149 (October 2010): 103–7. http://dx.doi.org/10.4028/www.scientific.net/amr.148-149.103.
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Deformation often appears in castings during casting and heat treatment processes, which determines the machining allowance setting and the machining size distribution of product. The paper presents a novel method for integrated simulation of the deformation behavior of castings during casting and heat treatment processes with a unified finite element model. Firstly, analyze the deformation of castings during casting process with the model containing mold and casting, and update the geometry of casting after casting process, then analyze the deformation of castings during heat treatment process and the final geometry shape of casting before machining could be obtained. By the method, investigation on the deformation behavior of a hydro turbine blade casting during casting and heat treatment processes was carried out, and the residual stress distribution and geometry shape of the casting were obtained.
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Ten, E. B., and O. A. Kol’. "Dependence of cast iron chill from its carbon equivalent." Izvestiya. Ferrous Metallurgy 63, no. 1 (March 30, 2020): 57–62. http://dx.doi.org/10.17073/0368-0797-2020-1-57-62.
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Numerical relation of cast iron chill characteristics (distance of chilled layer H and volume quota of ledeburite in it Qл ) with its carbon equivalent СE was investigared. This data helps to prognosticate with high probability the evolution of the surface chilled layer forming at the production of castings with different thickness from cast iron of various chemical compositions. The object of study is the unalloyed induction melted cast iron with eight variants of chemical composition with carbon equivalent from 3.30 up to 5.53 %. From these cast irons we made the step-by-step castings with steps sizes of 10×60 mm and thickness of 5, 10, 20 and 40 mm. The distance (depth) of chilled layer was measured at the fractures of the castings and gaged on thickness of full chill zone. Ledeburite volume quota was detected by metallographic method using “Nexsys-Image expert pro 3” computer program. According to experimental data, when the casting thickness is 5 and 10 mm the through (at all thickness) full chill is formed at carbon equivalent ≤ 4.08 % and ≤ 3.67 % consequently. At the castings with 20 and 40 mm thickness the zone of full chill is absent, and in this case the chilled layer depth increases with a decrease of carbon equivalent and decreases with an increase of casting’s thickness X. The dependence of H from СЕ have the exponential character and can be described by the equation H = A exp (–k СE ), where A and k are empirical coefficients. Ledeburite volume quota near the contact surface of casting with chiller is near 90 %, but with an increase in the distance from the surface it decreases with different intensity depending on changes of carbon equivalent and casting’s thickness. By mathematical processing of the experimental data received for the distance of 5 mm from the contact surface of the casting with chiller, we have detected that numerical re lation Qл in casting chilled layer with value of CE can be described by the exponential dependence
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Majernik, Jan, Stefan Gaspar, Jan Kmec, Monika Karkova, and Jozef Mascenik. "Possibility of Utilization of Gate Geometry to Modify the Mechanical and Structural Properties of Castings on the Al-Si Basis." Materials 13, no. 16 (August 11, 2020): 3539. http://dx.doi.org/10.3390/ma13163539.
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The mechanical properties of die castings correlate with the inner structure of a casting, distribution of the eutectic phases, and with the content and distribution of porous cavities in the casting volume. This submitted paper deals with the issue of the possibility to influence the basic parameters affecting the quality of castings through structural modifications of the gating system. The structural parameter under assessment is the gate height. In the case of the diverse height of the gate, five sets of castings were produced. The individual sets of castings were subjected to examination of selected mechanical properties, i.e., of permanent deformation and surface hardness. At the same time, the individual sets of castings were subjected to metallographic examination of the eutectic structure of the casting. It was proved that the gate height influences the aforementioned properties of the castings and significantly affects the ratio of the eutectic phases in the volume of the casting. The conclusion describes the mutual correlation between the gate structure, the mechanical properties of the casting, and its structural composition.
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Silva, Rui Pedro, Rui Soares, Rui Neto, Ana Reis, Ricardo Paiva, Rui Madureira, and José Silva. "Grain Refinement of Inconel 718 Superalloy—The Effect of Rotating Magnetic Field." Materials 15, no. 6 (March 10, 2022): 2038. http://dx.doi.org/10.3390/ma15062038.
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The effect of the application of a rotating magnetic field on the average grain size of IN718 castings was experimentally studied. For the purpose, four parts were produced by investment casting and characterized. The first casting was produced without application of RMF for comparison. The remaining ones were submitted to different RMF frequencies for 15 min and subsequently to the pouring of the nickel-based superalloy. In these three castings, the RMF frequencies applied were, respectively, 15 Hz, 75 Hz and 150 Hz. All the other process parameters were kept constant during the execution of the experimental procedure. The average grain size of the samples was determined according to the ASTM E112-13 standard, using intercept methods. Macro hardness measurements, tensile testing and SEM-EDS analysis were conducted in order to evaluate the casting’s mechanical properties and microstructures. The results demonstrate a noticeable grain size reduction in the samples submitted to rotating magnetic field. An average grain area reduction, greater than 96%, was achieved in the castings where RMF frequencies of 75 Hz and 150 Hz were applied. The application of RMF also caused a morphological change in the casting’s dendrites from cellular to almost equiaxed. Additionally, it originated the decrease of the size and amount of needle-like δ phase. Regarding mechanical properties of the cast parts, no major differences were verified.
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Chang, Qing Ming, Yin Kai Yang, Jing Yuan, and Xia Chen. "Numerical Simulation of Mold Filling and Solidification Behavior in Permanente Casting Process." Applied Mechanics and Materials 313-314 (March 2013): 179–83. http://dx.doi.org/10.4028/www.scientific.net/amm.313-314.179.
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Melt flow and casting solidification are essential parts of the permanent mold casting process and affect significantly the quality of castings．For this reason, accurate prediction of mold filling pattern and temperature field in permanent mold castings plays on an important role in producing sound castings. In this paper, the model filling and solidification of a box casting produced from an aluminum alloy is studied. Different casting processes are employed, simulated and optimized to obtain sound castings. Simulation results reveal that with appropriate gating system, pouring rate, cooling line, a smooth mold filling, reduced shrinkages and other defects are available and desired sound castings can be produced.
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Ahmed, Kamal. "Design and Development of LM24 plate Casting using Solid Cast Simulation Technique." International Journal for Research in Applied Science and Engineering Technology 12, no. 5 (May 31, 2024): 1202–9. http://dx.doi.org/10.22214/ijraset.2024.61786.
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Abstract: This research deals with the elimination of defects in aluminium alloy castings and enhancement in the casting yield and quality. The main intention of the work is to improve the quality of a cast component using Computer Aided Casting Simulation Software. SOLID Cast simulation software is used for simulating the solidification process of casting and visualizing outputs showing possible problematic areas or defects which may occur in the cast product. Plate Castings of aluminium alloy - LM 24 are produced with different designs of gating systems and tested for defects like porosity using Archimedes immersion Technique and also Radiographic testing is used to check the quality of the castings. The produced castings are observed to be sound, and the results obtained are in agreement with the simulation results. Hence it is verified that solidification simulation helps in improving the quality of castings without any shop-floor trails. Casting yield and percentage porosity values are determined for 12 castings produced with different gating systems. The best results are observed to be produced by the castings having a 1-Ingate system in horizontal or lateral positions.
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Chen, Yi, Gang Yang, Yi Yang, Kang Sheng Wang, and Chen Guang Lu. "Casting Process and Simulation of K19 Cylinder Block." Applied Mechanics and Materials 602-605 (August 2014): 311–15. http://dx.doi.org/10.4028/www.scientific.net/amm.602-605.311.
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Cylinder blocks are the most important parts of engine, and their qualities will fundamentally determine the efficiency of engine. In this work, the casting process of K19 engine cylinder block was studied. A casting process was designed and assessed by the numerical software MAGMA to produce cylinder block castings. An actual experiment of casting was carried out and the mechanical properties of the casting were examined. The simulation results show the liquid metal smoothly fills the casting mold and no shrinkage cavity and porosity are formed in the castings. The cylinder block produced by the actual experiment exhibits superior mechanical properties to common ones, which proves the casting process designed is suitable for producing high quality cylinder block castings. The research shows that numerical simulation can provide very useful guidance for the production of castings
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Odilov, Furkat, and Farrukhjon Abdullaev. "Improving The Technology Of Continuous Casting Of Steel Castings." American Journal of Engineering And Techonology 03, no. 04 (April 30, 2021): 108–17. http://dx.doi.org/10.37547/tajet/volume03issue04-17.
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This article describes the quality and cost-effectiveness of converting steels by melting them in electric arc furnaces. In addition, the technology of continuous casting of cast products in the furnace with the help of ferroalloys, followed by various equipment.
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Roskosz, Stanisław, Bartłomiej Dybowski, and Robert Jarosz. "Influence of Mould Cooling Rate on the Microstructure of AZ91 Magnesium Alloy Castings." Solid State Phenomena 191 (August 2012): 115–22. http://dx.doi.org/10.4028/www.scientific.net/ssp.191.115.
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Magnesium alloys are the lightest, widely used structural material. They are often used in aeronautical and automotive industries, where the weight savings are essential. Due to high responsibility of the elements made from magnesium alloys it is important to achieve high quality castings without any defects. The paper presents results of investigations on impact of sand mould cooling rate on microstructure and quality of the castings. Six identical castings, fed and cooled in different ways were investigated. Studies consisted of: RTG investigations and SEM and LM observations. Microstructure was evaluated qualitatively and quantitatively. RTG investigations showed that casting without feeder and cooler, casting only with feeder and castings cooled with 20mm and 40mm thick cooler contains voids inside. Castings with feeder and coolers 20mm and 400mm thick were flawless. Microstructure evaluation showed that castings with and without defects have different structure. Castings with defects were characterized by higher volume fraction of Mg17Al12 intermetallic phase. Flawless castings were characterized by fully divorced eutectic.
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Sadayappan, K., W. Kasprzak, Zach Brown, L. Quimet, and Alan A. Luo. "Characterization of Magnesium Automotive Components Produced by Super-Vacuum Die Casting Process." Materials Science Forum 618-619 (April 2009): 381–86. http://dx.doi.org/10.4028/www.scientific.net/msf.618-619.381.
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Magnesium automotive components are currently produced by high pressure die casting. These castings cannot be heat-treated to improve the strength and ductility mainly due to the casting imperfections such as porosity and inclusions created by the air entrainment during the turbulent mold filing. These imperfections also prevent magnesium components to be used for highly stressed body components. Efforts were made to produce high integrity magnesium castings through a Super-Vacuum Die Casting process. The AZ91D castings were found to have very low porosity and can be heat-treated without blisters. The tensile properties of the castings were satisfactory. The mechanical properties and thermal analysis indicate that the conventional heat treatment procedure needs to be optimized for such thin sectioned and rapidly solidified castings which have very fine microstructures.
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Cheng, Le, Hong Xing Lu, Qiang Zhu, Xiang Kai Zhang, Ai Di Shen, and Peng Yang. "Evolution of Microstructure and Mechanical Properties of Semi-Solid Squeeze Cast A356.2 Aluminum Alloy during Heat Treatment." Solid State Phenomena 285 (January 2019): 139–45. http://dx.doi.org/10.4028/www.scientific.net/ssp.285.139.
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Semi-solid squeeze casting (SS-SC) is a new processing technology which combines semi-solid processing (SSP) and squeeze casting (SC). In this process, semi-solid slurry fills mold by using its rheological property and solidifies under high pressure. It has several advantages, such as stable filling, small heat impact to the mold, low cost, high density and excellent mechanical properties of castings, which receives more and more attention. The microstructure of castings provided by SS-SC is quite different from that of casting provided by conventional SC in as-cast condition, which leads to differences in the evolution of microstructure and mechanical properties in heat treatment process. In this study, A356.2 aluminum alloys castings were provided by both SS-SC and conventional SC respectively. The evolution of microstructure and mechanical properties of castings during heat treatment was investigated to obtain the best mechanical properties of semi-solid squeeze castings. Keywords:Microstructure, Mechanical properties, Heat treatment, A356 alloy, Semi-Solid Squeeze Casting
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Prasanna, BG, M. Kalavathi, Bhuvana Sachin, TV Shreeharsha, B. Praveen, and Mallikarjuna Ragher. "Marginal Accuracy of Castings Fabricated with Ringless Casting Investment System and Metal Ring Casting Investment System: A Comparative Study." Journal of Contemporary Dental Practice 17, no. 2 (2016): 165–70. http://dx.doi.org/10.5005/jp-journals-10024-1821.
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ABSTRACT Background The thermal expansion of the investment can be restricted by the metal casting ring because the thermal expansion of the ring is less than that of the investment. The ringless casting procedure is in use in clinical dentistry, though there is little scientific data to support its use in fixed partial dentures. In this study, marginal discrepancy of castings produced with the ringless casting technique and the conventional technique using the metal rings were compared. Materials and methods A total of 30 wax patterns were fabricated directly on a metal die. Optical stereomicroscope was used to measure the marginal discrepancy between the metal die and wax patterns. A total of 15 castings were invested using Bellavest T phosphate-bonded investment with the ringless technique and 15 were invested with the same investment with a metal ring; 30 castings were produced using a nickel-chromium ceramo-metal alloy. The internal surface of the castings was not modified and seated with finger pressure. The vertical marginal discrepancy was measured using an optical stereomicroscope at a magnification of 100×. The data obtained were statistically analyzed using students t-test (paired t-test and unpaired t-test). Results The castings of the ringless technique provided less vertical marginal discrepancy (240.56 ± 45.81μ) than the castings produced with the conventional metal ring technique (281.98 ± 53.05μ). The difference was statistically significant. Conclusion The ringless casting technique had produced better marginal accuracy compared with conventional casting technique. Ringless casting system can be used routinely for clinical purpose. How to cite this article Kalavathi M, Sachin B, Prasanna BG, Shreeharsha TV, Praveen B, Ragher M. Marginal Accuracy of Castings Fabricated with Ringless Casting Investment System and Metal Ring Casting Investment System: A Comparative Study. J Contemp Dent Pract 2016;17(2):165-170.
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Nadolski, M., Z. Konopka, M. Łągiewka, and A. Zyska. "The Influence of the Mould Filling Conditions on the Quality of Castings Made of EN AC-44000 Alloy." Archives of Foundry Engineering 14, no. 2 (June 1, 2014): 19–22. http://dx.doi.org/10.2478/afe-2014-0029.
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Abstract The work deals with the influence of change in the filling conditions of the ceramic moulds with plaster binder on the presence of gaseous porosity and the microstructure of the achieved test castings with graded wall thickness. Castings made of EN AC-44000 alloy, produced either by gravity casting, or by gravity casting with negative pressure generated around the mould (according to the Vacumetal technology), or by counter-gravity casting were compared. The results of examinations concerning the density of the produced castings indicate that no significant change in porosity was found. The increased size of silicon crystals was found for the increased wall thicknesses due to the slower cooling and solidification of castings.
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Říhová, M., J. Cech, and J. Havlíčková. "Evaluation of Porosity in Al Alloy Die Castings." Archives of Foundry Engineering 12, no. 1 (January 1, 2012): 93–98. http://dx.doi.org/10.2478/v10266-012-0018-9.
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Evaluation of Porosity in Al Alloy Die Castings Mechanical properties of an Al-alloy die casting depend significantly on its structural properties. Porosity in Al-alloy castings is one of the most frequent causes of waste castings. Gas pores are responsible for impaired mechanical-technological properties of cast materials. On the basis of a complex evaluation of experiments conducted on AlSi9Cu3 alloy samples taken from the upper engine block which was die-cast with and without local squeeze casting it can be said that castings manufactured without squeeze casting exhibit maximum porosity in the longitudinal section. The area without local squeeze casting exhibits a certain reduction in mechanical properties and porosity increased to as much as 5%. However, this still meets the norms set by SKODA AUTO a.s.
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Gašpár, Štefan, Tomáš Coranič, Ján Majerník, Jozef Husár, Lucia Knapčíková, Dominik Gojdan, and Ján Paško. "Influence of Gating System Parameters of Die-Cast Molds on Properties of Al-Si Castings." Materials 14, no. 13 (July 5, 2021): 3755. http://dx.doi.org/10.3390/ma14133755.
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The resulting quality of castings indicates the correlation of the design of the mold inlet system and the setting of technological parameters of casting. In this study, the influence of design solutions of the inlet system in a pressure mold on the properties of Al-Si castings was analyzed by computer modelling and subsequently verified experimentally. In the process of computer simulation, the design solutions of the inlet system, the mode of filling the mold depending on the formation of the casting and the homogeneity of the casting represented by the formation of shrinkages were assessed. In the experimental part, homogeneity was monitored by X-ray analysis by evaluating the integrity of the casting and the presence of pores. Mechanical properties such as permanent deformation and surface hardness of castings were determined experimentally, depending on the height of the inlet notch. The height of the inlet notch has been shown to be a key factor, significantly influencing the properties of the die-cast parts and influencing the speed and filling mode of the mold cavity. At the same time, a significant correlation between porosity and mechanical properties of castings is demonstrated. With the increasing share of porosity, the values of permanent deformation of castings increased. It is shown that the surface hardness of castings does not depend on the integrity of the castings but on the degree of subcooling of the melt in contact with the mold and the formation of a fine-grained structure in the peripheral zones of the casting.
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Gavariev, Renat V., and Ksenia N. Gavarieva. "Features of Casting Magnesium Alloys in Chill Mold." Materials Science Forum 1052 (February 3, 2022): 287–91. http://dx.doi.org/10.4028/p-679e24.
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The article describes the features of the casting process in the chill mold of magnesium alloys. The main factors affecting the quality of the castings obtained are indicated. The main defects of magnesium castings obtained by chill mold casting, as well as possible ways to eliminate them, are revealed. Options for improving the efficiency of the casting process by optimizing the process parameters are proposed, as well as options for heat treatment that increase the physical and mechanical properties of ready-made castings are presented.
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Boroń, Kinga. "Evaluation of porosity of AlZn5Mg castings made by squeeze casting technology." Acta Innovations, no. 32 (July 1, 2019): 12–19. http://dx.doi.org/10.32933/actainnovations.32.2.
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The paper shows the results of research aimed to assess the impact of high squeeze pressure on the porosity of AlZn5Mg alloy castings, including its distribution in slab-type castings with dimensions of 25 x 100 x 200 mm. The research was carried out on castings made by two methods: squeeze casting and gravity casting. The pressing was conducted at a pressure of 100 MPa at an initial mould temperature of 200°C. The research identified the middle and outer parts of the casting. Experimental research was preceded by numerical simulation of the casting solidification, then a porosity assessment was carried out using the hydrostatic weighing method, which was supplemented by structural observations. The results of the research showed a two-fold decrease in the porosity in the middle part of the casting which is most exposed to the occurrence of shrinkage voids formed in the final clotting phase. Structural tests revealed the occurrence of dispersed porosity in castings, mainly of shrinkage and / or shrinkage-gas origin. The impact of pressure of 100 MPa during solidification caused fragmentation of the primary structure of castings, which resulted in a higher grain density.
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Zýka, Jiří, Irena Andršová, Božena Podhorná, and Karel Hrbáček. "Mechanical Properties and Microstructure of IN738LC Nickel Superalloy Castings." Materials Science Forum 782 (April 2014): 437–40. http://dx.doi.org/10.4028/www.scientific.net/msf.782.437.
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IN738LC is a cast nickel-base superalloy developed for applications requiring high strength at elevated temperatures. Its balanced composition provides a good combination of tensile and creep-rupture properties as a result of gamma prime precipitate strengthening enhanced by solid solution and grain-boundary strengthening. Experimental castings are used in heat treated state. This alloy is used widely, for example, for manufacturing of gas turbine blades. Recently, customers demand different weight of castings hence different conditions during solidifying and cooling of the castings originate, resulting in different castings microstructure. When approving the castings, mechanical values are measured by tensile test on test bars made from the cast blade roots. This work investigates mechanical properties casting structure correlations, particularly grain, casting defects, carbides.
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Eperješi, Š., M. Matvija, ľ. Eperješi, and M. Vojtko. "Evaluation of Cracking Causes of AlSi5Cu3 Alloy Castings." Archives of Metallurgy and Materials 59, no. 3 (October 28, 2014): 1089–92. http://dx.doi.org/10.2478/amm-2014-0187.
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Abstract Recently, the castings made from aluminum-silicon alloys by pressure die casting are increasingly used in the automotive industry. In practice, on these castings are high demands, mainly demands on quality of their structure, operating life and safety ensuring of their utilization. The AlSi5Cu3 alloy castings are widely used for production of car components. After the prescribed tests, the cracks and low mechanical properties have been identified for several castings of this alloy, which were produced by low pressure casting into a metal mould and subsequent they were heat treated. Therefore, analyses of the castings were realized to determine the causes of these defects. Evaluation of structure of the AlSi5Cu3 alloy and causes of failure were the subjects of investigation presented in this article.
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Prikhod’ko, O. G., V. B. Deev, E. S. Prusov, and A. I. Kutsenko. "Influence of thermophysical characteristics of alloy and mold material on castings solidification rate." Izvestiya. Ferrous Metallurgy 63, no. 5 (July 1, 2020): 327–34. http://dx.doi.org/10.17073/0368-0797-2020-5-327-334.
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Obtaining castings of given quality is the main task of foundry production. One of the stages of casting technology is solidification of melt in the mold. When studying the process of castings solidification, it is necessary to fully take into account all the features of heat transfer between casting and mold. Influence of various thermophysical parameters of alloy and mold material on casting formation is considered. In the analysis, original mathematical models were used to calculate the coefficient and time of complete solidification of castings in sand-clay and metal forms. These models take into account geometric parameters of casting, main thermophysical parameters of casting metal and mold material, heat transfer conditions at crystallization front, on casting-mold boundary and on the mold surface. Analysis of dependence of time and rate of castings solidification on thermophysical parameters (heat capacity, density, heat conductivity of casting material and mold, specific heat of metal crystallization) was carried out. Storage capacity and process of heat storage are quite fully characterized by the value of heat storage coefficient. This coefficient practically determines the rate of heat loss by the casting which plays a decisive role in its properties forming. Therefore, this parameter is selected for a comprehensive analysis of thermal processes occurring in casting and mold. The influence of thickness and thermal conductivity of chill paint layer on solidification of castings in metal molds is considered. The basic calculation formulas and initial data are presented. Calculations were carried out for castings of the following types: endless plate, endless cylinder, ball. The results of simulation of solidification process parameters are presented in graphic form. Using various alloys as an example, it has been shown by calculation that when changing composition and properties of mold material, it is possible to change time and speed of alloys solidification in a wide range. In this case, processes of forming the structure and properties of castings are controlled.
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Wang, Yingli, and Fengxian Wang. "Key Analysis of Design and Numerical Simulation for Aluminum Alloy Impeller Low-pressure Casting Mold." Journal of Physics: Conference Series 2338, no. 1 (September 1, 2022): 012070. http://dx.doi.org/10.1088/1742-6596/2338/1/012070.
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Abstract It is of great practical value to complete the low-pressure casting of aluminum alloy impeller in the current development of low-pressure casting process. In the research, it is necessary to focus on factory realization and use low-pressure casting to produce aluminum alloy impellers, so that impeller castings with compact structure and meeting performance requirements can be obtained. Compared with other casting methods, low-pressure casting itself, as a precision casting method, can be cast on the metal solution with lower pressure in the application process. The castings can be filled and solidified under certain pressure, and the castings with compact structure can be obtained. In the research, Pro / Engineer is used to design the low-pressure casting mold for aluminum alloy impeller, and MAGMASOFT is used to carry out the filling and solidification process of aluminum alloy impeller. Through numerical simulation, we can accurately predict the defects of impeller castings, and optimize the mold scheme and pressure-time parameters according to the prediction results.
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Li, Jiquan, Long Chen, Shaofei Jiang, Huiqi Gan, and Weina Hao. "Numerical Simulation and Process Optimization of Magnesium Alloy Vehicle Dashboard Cross Car Beam (CCB) Based on MAGMA." Processes 11, no. 1 (December 22, 2022): 16. http://dx.doi.org/10.3390/pr11010016.
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At present, the qualified rate of large thin-walled magnesium alloy castings is low. In this study, the effects of mold structure and process parameters were investigated to improve the production qualification rate of castings. The filling process of die castings was simulated by numerical simulation technology to optimize their structure. On the basis of an optimized mold structure, the process parameters of die castings were optimized using a response surface model, and a group of optimal process combinations were obtained: pouring temperature—660 °C; mold preheating temperature—200 °C; injection speed—6.5 m/s. The rationality of the optimized mold structure and process parameters is verified by die-casting experiments. The results show that the optimized mold structure and process parameters can effectively reduce the internal shrinkage cavity casting defects of automotive CCB castings, and effectively improve the production qualification rate of magnesium alloy CCB castings. This research has important guiding significance for the production of large thin-walled magnesium alloy parts.
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Yang, Xiang Jie, Yi He, Yong Bo Zhu, Chuan Lin Hu, Hong Min Guo, Yun Hai Jing, and Guang Bin Yi. "The Study of A356 Alloy Rheo-Squeeze Casting Process." Solid State Phenomena 256 (September 2016): 270–75. http://dx.doi.org/10.4028/www.scientific.net/ssp.256.270.
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In this paper, the castings of A356 alloy were made by the rheo-squeeze casting with slurry-making from the process of LSPSF. Experiments were designed to study the influence of three parameters in rheo-squeeze casting process, such as injection speed, mould preheating temperature and injection pressure, on castings performance. The results show that high-quality castings were produced with the injection speed of 0.5m/s ,the mould preheating temperature of 240°C, the injection pressure of 50MPa. The mechanical properties, such as the yield strength, tensile strength and elongation of the castings with T6 heat treatment are 241 MPa, 328MPa and 11.6%, respectively.
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Morey, E. F., and R. Earnshaw. "The Fit of Gold-alloy Full-crown Castings Made with Pre-wetted Casting Ring Liners." Journal of Dental Research 71, no. 12 (December 1992): 1858–64. http://dx.doi.org/10.1177/00220345920710120101.
Full textAbstract:
Measurements were made of the fit of full-crown gold-alloy castings produced with two types of pre-wetted ring liner (asbestos and cellulose) and a typical gypsum-bonded investment (Cristobalite Inlay, Sybron/Kerr Products, Romulus, MI; W/P = 0.40). Laboratory measurements were made of the effects of the liners on potential investment expansion, and properties of the lining materials considered relevant to casting accuracy were also measured. There was a wide variation in values for mean dimensional inaccuracy. One liner produced a series of castings all of whose inaccuracies lay within the range ± 0.1%, with a mean value of + 0.01%. With the other five liners, all or most castings were undersize. With three, all or most castings showed inaccuracies worse than -0.2%. The values for casting inaccuracy with the various liners showed a probable correlation with potential investment expansion (p < 0.05); however, no correlation was found between casting inaccuracy and any apparently relevant liner properties, alone or in combination. In casting techniques which use a pre-wetted ring liner, the choice of a specific lining material is an important factor which has a significant effect on casting inaccuracy. With at least three of the six liners tested, a higher investment expansion was needed for accurate full-crown castings to be ensured.
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Earnshaw, R., and E. F. Morey. "The Fit of Gold-alloy Full-crown Castings Made with Ceramic Casting Ring Liners." Journal of Dental Research 71, no. 12 (December 1992): 1865–70. http://dx.doi.org/10.1177/00220345920710120201.
Full textAbstract:
Measurements were made of the fit of gold-alloy full-crown castings produced with dry ceramic ring liners. When used with vacuum investing, these liners absorb relatively large amounts of water from the investment mix (thereby reducing its original W/P ratio) and then function as wet liners, thus increasing the investment's potential expansion and giving castings which are consistently larger than when air investing is used. With four of the five liners tested, investing in air produced many castings which were unacceptably undersized (inaccuracy worse than -0.2%). The fifth liner, an industrial material 2 mm thick, gave only one casting out of 12 which was outside this limit, although all castings were undersized to a lesser extent. Vacuum investing gave improved casting accuracy; with four of the five liners, the improvement was highly significant (p < 0.001), and with the fifth, probably significant (p < 0.05). Even with vacuum investing, however, with only two of the liners did all castings show inaccuracies within ± 0.2%. With the other three liners, some castings (ranging from 2/10 to 7/9) had inaccuracies worse than -0.2%. With both air and vacuum investing, changing from one liner to another caused changes in relative casting accuracy which were often significant (p < 0.01) or highly significant (p < 0.001). In casting techniques where a ceramic ring liner is used, the choice of specific lining material and the choice between investing in air or under vacuum are important factors which can have a major effect on the fit of castings.
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Wang, Ao Bing, Li Ping Zhang, Liu Peng, and Li Yong Ni. "Casting Die Designing for Drive Cover." Applied Mechanics and Materials 378 (August 2013): 346–49. http://dx.doi.org/10.4028/www.scientific.net/amm.378.346.
Full textAbstract:
The driving covers casting with complex shape belongs to irregular casting. According to the requirements of size and performance of the thin-walled castings, the expanding-type runner of the trapezoid shape section was adopted, conducive to the production of thin-walled castings. The parting surfaces of the die-casting die are the interface of the movable die and fixed die and that of left and right slider. The left and right slider would be reset by spring. Proved by actual production, the mold operated smoothly, without clamping stagnation, and the production of die castings meet delivery requirements.
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Chechukha, V. I., and M. A. Sadokha. "Defects in high‑pressure die casting and measures to prevent gas defects." Litiyo i Metallurgiya (FOUNDRY PRODUCTION AND METALLURGY), no. 4 (December 15, 2023): 16–24. http://dx.doi.org/10.21122/1683-6065-2023-4-16-24.
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The formation of defects in the manufacturing of castings is influenced by numerous factors. These factors can affect the quality both individually and in combination. This article provides a characterization of the defects encountered in high‑pressure die casting and identifies the factors influencing their formation. Effective measures are examined to reduce casting defects, which are recommended for obtaining critical and highly demanding castings with stringent surface requirements after mechanical processing.The use of automated high‑pressure die casting complexes in production has a positive impact on the quality of castings, eliminating many of the potential causes of defects related to human factors.
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Palutkiewicz, Paweł. "The new method of manufacturing porous castings from styrene–acrylic dispersion." Cellular Polymers 37, no. 4-6 (July 2018): 206–23. http://dx.doi.org/10.1177/0262489318797513.
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This work presents an innovative method for producing porous castings from polymer dispersion with wood flour. The method described for forming porous castings from blends, in which the aqueous dispersions of polymers are binders, enables the manufacturing of wood-like products with a cork-like structure. The casting technology and selected properties of finished castings (density, compression strength) are presented. The structurual investigations of the obtained castings are also presented.
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Binczyk, F., J. Cwajna, P. Gradoń, M. Mańka, and R. Findziński. "Surface Modification of Cored, Thin Walled Castings of Nickel Superalloy IN-713C." Archives of Foundry Engineering 15, no. 3 (September 1, 2015): 17–20. http://dx.doi.org/10.1515/afe-2015-0051.
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Abstract In current casting technology of cored, thin walled castings, the modifying coating is applied on the surface of wax pattern and, after the removal of the wax, is transferred to inner mould surface. This way the modification leading to grain refinement occur on the surface of the casting. In thin walled castings the modification effect can also be seen on the other (external) side of the casting. Proper reproduction of details in thin walled castings require high pouring temperature which intensify the chemical reactions on the mould – molten metal interface. This may lead to degradation of the surface of the castings. The core modification process is thought to circumvent this problem. The modifying coating is applied to the surface of the core. The degradation of internal surface of the casting is less relevant. The most important factor in this technology is “trough” modification – obtaining fine grained structure on the surface opposite to the surface reproduced by the core.
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Chechukha, V. I., and M. A. Sadokha. "Defects in castings during high‑pressure casting and measures to prevent their formation." Litiyo i Metallurgiya (FOUNDRY PRODUCTION AND METALLURGY), no. 1 (April 10, 2024): 26–31. http://dx.doi.org/10.21122/1683-6065-2024-1-26-31.
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The article presents a list of defects in castings formed during high‑pressure casting. It has been established that each cause that creates conditions for the formation of specific defects in castings is interconnected with the incorrect setting of specific casting technological parameters. Measures to prevent the formation of defects have been determined depending on the casting technological parameters, operating modes of the mold, application of release lubricant, and alloy preparation. To ensure high quality of produced castings, it is necessary to minimize the influence of the human factor during the casting process. This can be achieved by using modern foundry equipment, high‑quality charge and auxiliary materials, and by applying automated high‑pressure casting complexes in serial and mass production.
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Lu, Hong Xing, You Feng He, Stephen Midson, Da Quan Li, and Qiang Zhu. "Controlling and Minimizing Blistering during T6 Heat Treating of Semi-Solid Castings." Solid State Phenomena 256 (September 2016): 192–98. http://dx.doi.org/10.4028/www.scientific.net/ssp.256.192.
Full textAbstract:
Surface blistering during T6 heat treating is an artifact that is essentially unique to high pressure casting processes such as semi-solid casting and die casting. It is believed that the blistering originates from subsurface defects present in the castings. When the castings are exposed to elevated temperatures during solution heat treatment, the strength of the aluminum is reduced, and the defects expand to deform the surfaces of the castings. There are three potential sources for the subsurface defects - entrapped air, die lubricant or shot sleeve lubricant.This paper will report on a study to determine the origin of the defects present in the castings that produce the blisters. Along with attempting to separate the influence of air and the two types of lubricants on blister formation, the study will also examine the impact of a number of process parameters on blistering.
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Acimovic-Pavlovic, Zagorka, Milutin Djuricic, Sasa Drmanic, and Rade Djuricic. "The influence of the parameters of lost foam process on the quality of aluminum alloys castings." Chemical Industry 64, no. 2 (2010): 121–27. http://dx.doi.org/10.2298/hemind100301011a.
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This paper presents the research results of application of Lost foam process for aluminum alloys castings of a simple geometry. The process characteristic is that patterns and gating of moulds, made of polymers, stay in the mould till the liquid metal inflow. In contact with the liquid metal, pattern intensely and in relatively short time decomposes and evaporates, which is accompanied by casting crystallization. As a consequence of polymer pattern decomposition and evaporation a great quantity of liquid and gaseous products are produced, which is often the cause of different types of casting errors. This paper presents the results of a research with a special consideration given to detecting and analyzing the errors of castings. In most cases the cause of these errors are defects of polymer materials used for evaporable patterns production, as well as defects of materials for refractory coatings production for polymer patterns. The researches have shown that different types of coatings determine properties of the obtained castings. Also, the critical processing parameters (polymer pattern density, casting temperature, permeability of refractory coating and sand, construction of patterns and gating of moulds) significantly affect on castings quality. During the research a special consideration was given to control and optimization of these parameters with the goal of achieving applicable castings properties. The study of surface and internal error of castings was performed systematically in order to carry out preventive measures to avoid errors and minimize production costs. In order to achieve qualitative and profitable castings production by the method of Lost foam it is necessary to reach the balance in the system: evaporable polymer pattern - liquid metal - refractory coating - sandy cast in the phase of metal inflow, decomposition and evaporation of polymer pattern, formation and solidification of castings. By optimizing the processing parameters castings of required structural and mechanical characteristics could be achieved, casting defects characteristic for this process could be avoided with the result of the production costs saving. The presented results can be useful to define parameters of Lost foam process and its application in practice with objective to obtain castings with in advance specified quality.
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Dong, Yi, Xiao Ming Fan, and Bin Liu. "Numerical Simulation and Technology Optimization of Rear Oil Seal Bearing Die Castings Based on ProCAST." Advanced Materials Research 189-193 (February 2011): 4008–13. http://dx.doi.org/10.4028/www.scientific.net/amr.189-193.4008.
Full textAbstract:
In production,the Φ105 mm hole of rear oil seal bearing die castings often appear porosity, shrinkage and other defects , resulting in the parts to scrap. The existing gating system design of rear oil seal bearing die castings was improved , and the flow and temperature field of the two programs that before and after improvement were analyzed by ProCAST software. The simulation results predicted the casting defects, and the conclusion was consistent with the production. By using the improved process optimization, the rejection rate of die castings can be reduced effectively. Die casting is a chipless forming of casting with high casting dimensional accuracy, high surface quality and high production efficiency [1,2]. Therefore, it has developed rapidly in the automotive, communications and other industries. However, due to shrinkage, porosity and other reasons, leading to high rejection rate of castings. With the emergence of commercial casting simulation software, the casting production has been developed from semi empirical and semi theoretical onto theorization, quantification and controllable track[3-5]. In this paper, the casting defects of rear oil seal bearing is analyzed by using numerical simulation technology[6]. By optimizing the casting process, the casting quality is improved, and the rejection rate is reduced effectively.
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Battaglia, Eleonora, Franco Bonollo, Elena Fiorese, and Giorgio Kral. "Overview of the Correlations between Process Parameters, Microstructure and Mechanical Properties of Reference Castings and Industrial Demonstrators." Key Engineering Materials 710 (September 2016): 35–40. http://dx.doi.org/10.4028/www.scientific.net/kem.710.35.
Full textAbstract:
Among the Aluminum casting processes, High Pressure Die Casting (HPDC) is an efficient, versatile and economic way for producing large number of components. Nevertheless, because of the elevated amount of rejected castings, it is important to know which are the main causes of defect formation and their effects on microstructure and mechanical properties. This paper presents, within the European MUSIC project, an overview of the preliminary correlations obtained studying both castings with defect generator geometry, referred to as Horse-shoe Reference Castings, and industrial demonstrators, referred to as Gear Box Housing. The deduced correlations between static mechanical properties and casting defects highlighted interesting trends in both cases.
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Jiang, Meng, Yang Yang, and Hong Feng Zhang. "Design of Time-Lapse Core-Pulling Mechanism with Side Slide in Die-Casting Die." Advanced Materials Research 557-559 (July 2012): 1235–38. http://dx.doi.org/10.4028/www.scientific.net/amr.557-559.1235.
Full textAbstract:
In the process of die-casting die design, the die castings should be usually left in the moving die in order to design ejecting mechanism conveniently when open mould. For the special structure of die castings, when lateral side core-pulling mechanism and larger wrapping force on the fixed-die core than on the moving-die core are required, the time-lapse core-pulling mechanism with side slide block can be adopted, which can make die castings left in the moving-die after open mould, and assure die castings production to do successfully. Time-lapse core-pulling mechanism with side slide block is ingenious and simple, and doesn’t increase the production cost of die casting die, and has certain reference value to the design of it.
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Lin, Xuedong, Changming Liu, Linxian Che, and Jian Sun. "Study on the preparation technology of centrifugal Al-18Si-X composite reinforced with in situ particles." Journal of Physics: Conference Series 2338, no. 1 (September 1, 2022): 012014. http://dx.doi.org/10.1088/1742-6596/2338/1/012014.
Full textAbstract:
Abstract Al-18Si-X (X=Mg, Ti, Ni) composite tubular castings were prepared by centrifugal casting. The microstructure of cylindrical casting of Al-18Si-X composite was observed along the radial direction, and the segregation behavior and distribution characteristics of primary particles formed in different alloys under the action of centrifugal field were studied. The results show that the in situ particles in Al-18Si-7Mg, Al-18Si-7Ti, and Al-18Si-7Ni tubular castings have different segregation behaviors under the action of centrifugal field, which results in the formation of particle reinforcing layers in different regions of the castings. It is found that the volume fraction, size and particle morphology of primary particles in particle reinforcement layer of different castings are different.
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Vasková, I., M. Hrubovčáková, J. Malik, and Š. Eperješi. "Influence of Technological Parameters of Furane Mixtures on Shrinkage Creation in Ductile Cast Iron Castings." Archives of Metallurgy and Materials 59, no. 3 (October 28, 2014): 1037–40. http://dx.doi.org/10.2478/amm-2014-0174.
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Abstract Ductile cast iron (GS) has noticed great development in last decades and its boom has no analogue in history humankind. Ductile iron has broaden the use of castings from cast iron into areas, which where exclusively domains for steel castings. Mainly by castings, which weight is very high, is the propensity to shrinkage creation even higher. Shrinkage creation influences mainly material, construction of casting, gating system and mould. Therefore, the main realized experiment was to ascertain the influence of technological parameters of furane mixture on shrinkage creation in castings from ductile iron. Together was poured 12 testing items in 3 moulds forto determine and compare the impact of various technological parameters forms the propensity for shrinkage in the casting of LGG.
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Gavariev, R. V., and I. A. Savin. "Improvement of Surface Quality of Casting Produced by Casting under Pressure." Solid State Phenomena 265 (September 2017): 988–93. http://dx.doi.org/10.4028/www.scientific.net/ssp.265.988.
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The article considers the surface roughness of compression molds castings received by casting under pressure depending on the condition of the form-building surface. The technological process of casting under pressure is presented for the "Strike plate" product, concrete technological parameters values are specified. The pilot studies of the roughness of the castings throughout the entire period of operation of a compression mold are conducted. Based on the received values the recommendations about improvement of quality of a surface of castings by drawing sheetings are submitted by phisical vapour deposition method.
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Jiang, Yan, Yong Su, Ping Hu, and Wen Ping Chen. "Die Casting Mold Design of Auto Oil Pump Bracket." Advanced Materials Research 652-654 (January 2013): 2460–64. http://dx.doi.org/10.4028/www.scientific.net/amr.652-654.2460.
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This paper introduces a die-casting mold design process. On the basis of the shape of Car oil pump support, central of castings’ side face was selected as the mold joint; due to the design requirements of pouring system, we chosen bias running system. Castings’ size was calculated by requirement of die casting machine, then accomplished designs of molding and structure’s components. Because through holes which on the side face of castings are not deep, angular pin core puller is competent, at last, the final assembly of the mold and the simulation is completed.
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Bauer, Branko, Ivana Mihalic Pokopec, Mitja Petrič, and Primož Mrvar. "Effect of Si and Ni Addition on Graphite Morphology in Heavy-Section Spheroidal Graphite Iron Parts." Materials Science Forum 925 (June 2018): 70–77. http://dx.doi.org/10.4028/www.scientific.net/msf.925.70.
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Metallographic analysis is applied to the study of the chunky graphite morphology in heavy-section castings of spheroidal graphite cast irons. Three castings with different Si and Ni content were prepared. Three positions in casting from the edge to the centre, with different cooling rates, were chosen for microstructure observation. The effect of the Si and Ni content on the graphite morphology and mechanical properties of heavy-section spheroidal graphite cast iron parts were investigated. Cerium containing commercial inoculant was used for in-stream inoculation. Chunky graphite area was estimated in micro-and macrostructure. Mechanical properties were determined on tensile test bars taken from the centre of the casting. Macro-and microstructure examination showed that the castings with high Si-content and Ni addition had chunky graphite present, while the castings produced by use of low Si and Ni containing charge had no chunky graphite. High Si-content is strong chunky graphite promoter, especially in castings with slow cooling rate. Ni addition also promotes chunky graphite formation, but only in thermal centre of the casting (where the cooling rate is the lowest). The elongation is severely lowered when chunky graphite appears in the microstructure.
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Yu, Hai Liang, Jin Wu Kang, and Tian You Huang. "Simulation and Control of Distortion of Hydro Turbine Blade Steel Casting in Heat Treatment Process." Materials Science Forum 706-709 (January 2012): 1580–85. http://dx.doi.org/10.4028/www.scientific.net/msf.706-709.1580.
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Blades are key part of hydro turbines, which often distorts during heat treatment process for their special structures. In this paper, thermal fluid finite element simulation of the forced air cooling process of a blade casting was carried out under a variety of distances between fans and blades, air speeds, groups of fans and circumstance temperatures. The temperature fields of blade castings were obtained. A novel parameter, temperature difference between surfaces of castings along thickness direction, was proposed to analyze the distortion of blade castings. The distortion behavior of blade castings with martensitic stainless steel were discussed, which is in good agreement with distortion regularity of the experimental ones. The temperature differences between blade casting surfaces are always greater than zero, resulting in distortion which could be divided into three stages. Finally, we focused on discussing the control methods of distortion behavior of blade castings which could be operated in actual production.
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Vanko, Branislav, Ladislav Stanček, and Roman Moravčík. "EN AW-2024 Wrought Aluminum Alloy Processed by Casting with Crystallization under Pressure." Strojnícky casopis – Journal of Mechanical Engineering 67, no. 2 (November 1, 2017): 109–16. http://dx.doi.org/10.1515/scjme-2017-0024.
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AbstractBy using the wrought aluminum alloys can be created castings with higher mechanical properties than the castings made of standard foundry aluminum alloys, but it is necessary to handle the process of making sound castings without any defects such as hot tears and shrinkage porosity. In experiments, we have been studied of wrought aluminum alloy EN AW-2024 which has been processed by the casting with crystallization under pressure with forced flow. Castings were heat treated by standard T6 heat treatment.
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Скрябин, М. Л. "Effect of the chemical composition of 35HGSL steel on shrinkage, casting defects and microstructure." Informacionno-technologicheskij vestnik, no. 1(23) (March 11, 2020): 171–79. http://dx.doi.org/10.21499/2409-1650-2020-23-1-171-179.
Full textAbstract:
Стальные отливки на сегодняшний день стали неотъемлемой частью современного литейного производства. В процессе получения отливок неизбежно появляются какие-либо дефекты. В данной работе рассмотрены причины образования дефектов при изготовлении отливок из стали 35ХГСЛ при литье по выплавляемым моделям. Также рассмотрены особенности отвода теплоты от отливки при первичной и вторичной кристаллизации. Приведена классификация зон отливок по ориентации кристаллов в отливках. Выявлена закономерность влияния интенсивности охлаждения на характер усадки. Today, steel castings have become an integral part of modern foundry production. In the process of obtaining castings, any defects inevitably appear. In this paper, we consider the production reasons for the formation of defects in the manufacture of castings made of 35XGSL steel when casting on investment models. The features of heat removal from the casting during primary and secondary crystallization are also considered. The classification of casting zones by the orientation of crystals in castings is given. The regularity of the influence of the cooling intensity on the shrinkage character is revealed.
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Nadolski, M., Z. Konopka, M. Łągiewka, and A. Zyska. "The Influence of the Method of Mould Filling on the Quality of Castings Made of EN AC-44000 or EN AC-46200 Alloy." Archives of Foundry Engineering 14, no. 4 (December 1, 2014): 73–76. http://dx.doi.org/10.2478/afe-2014-0089.
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Abstract The performed examinations concerning the process of filling the plaster ceramic moulds with aluminium alloys allowed to assess the influence of various methods of introducing the metal into the mould cavity on the macro- and microstructure of the obtained experimental castings. The comparison was performed for castings with graded wall thickness made either of EN AC-44000 alloy or of EN AC-46000 alloy, produced either by gravity casting, or by gravity casting with negative pressure generated around the mould (according to the Vacumetal technology), or by counter-gravity casting. It was found that the silicon crystals grow in size with an increase in wall thickness due to the slower cooling and solidification of castings
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Pasko, Ján, Stefan Gaspar, and Juraj Ružbarský. "Die Casting Defects of Castings from Silumin." Applied Mechanics and Materials 510 (February 2014): 91–96. http://dx.doi.org/10.4028/www.scientific.net/amm.510.91.
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The production of die castings cast into a metal mold has in recent years achieved an expansive growth in the volume as well as the range of production and that is particularly in aviation and automobile industry. A primary criterion for achieving reliability, efficiency and quality of production is to ensure minimization of the castings defects occurrence. For this reason it is necessary to describe the type, scope and frequency of die castings defects and to define the cause of their occurrence.
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Vanko, B., and L. Stanček. "Utilization of Heat Treatment Aimed to Spheroidization of Eutectic Silicon for Silumin Castings Produced by Squeeze Casting." Archives of Foundry Engineering 12, no. 1 (January 1, 2012): 111–14. http://dx.doi.org/10.2478/v10266-012-0021-1.
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Utilization of Heat Treatment Aimed to Spheroidization of Eutectic Silicon for Silumin Castings Produced by Squeeze Casting This paper describes the possibility of using very short periods of solution annealing in the heat treatment of unmodified hypoeutectic silumin alloy AlSi7Mg0,3 casted by method of casting with crystallization under pressure with forced convection (direct squeeze casting process). Castings prepared at different casting parameters were subjected to special heat treatment called SST (Silicon Spheroidization Treatment), which were originally used only for the modified silumin alloys to spheroidization of eutectic silicon. Temperature holding time in solution annealing of T6 heat treatment is limited in the SST process to only a few minutes. It was studied the effect of casting parameters and periods of solution annealing on ultimate strength, yield strength, and especially ductility that in the unmodified silumin alloy castings is relatively low.