Journal articles: 'Martensitic stainless steel Metallography'

1

Ye, Youjun, Jing Li, Xingxing Lv, and Lin Liu. "Study on Failure Mechanism and Phase Transformation of 304 Stainless Steel during Erosion Wear." Metals 10, no. 11 (October 27, 2020): 1427. http://dx.doi.org/10.3390/met10111427.

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In this paper, the failure mechanism and phase transformation process of 304 stainless steel during the erosion wear process were studied with a rotary erosion wear test device. The surface morphologies of the worn 304 stainless steel were investigated by scanning electron microscopy (SEM). The metallographic structures of the nonworn and worn 304 stainless steel were analyzed by optical microscope (OM) and transmission electron microscopy (TEM). In addition, the surface hardness on different areas of the sample was also measured. The results demonstrated that the failure mechanism of 304 stainless steel during the process of erosion wear was cutting and spalling caused by plastic deformation. The high-density dislocations move along the slip planes between slip lines, which resulted in the formation of martensite phase between the slip lines. Meanwhile, the martensitic transformation on the worn surface caused by severe plastic deformation was the coordination of dislocation martensite and twin martensite.

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Triadi, Syahwira Taqwa, Cherly Selindiana, Hermawan Judawisastra, Aditianto Ramelan, and Rochim Suratman. "Dynamic Plastic Deformation Induced by Repetitive Hammering on Cr-Mn Austenitic Stainless Steel." Metalurgi 37, no. 1 (June 23, 2022): 7. http://dx.doi.org/10.14203/metalurgi.v37i1.618.

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Austenitic stainless steels have advantages, such as high ductility and good corrosion resistance. The cold working process can increase the hardness and strength of the material. However, because a metastable austenite phase occurs in that material, there is a phase change of γ austenite to α’-martensite and ε-martensite, which will reduce the ductility and its corrosion resistance. The strengthening process with dynamic plastic deformation (DPD) can prevent the formation of martensitic phases through repeated impact at high strain rates. This study analyzed microstructures and hardness evaluation on Cr-Mn austenitic stainless steel due to dynamic plastic deformation through the repetitive hammering method. Repetitive hammering with a strain rate of 6,2 s-1 on Cr-Mn austenitic stainless steels was carried out on five specimens with variations in the impact of 50, 100, 150, 250, and 350 times with impact energy of 486 J/cm2, 2.207 J/cm2, 2.569 J/cm2, 6.070 J/cm2, and 11.330 J/cm2 respectively. Microstructure, hardness, and XRD (X-ray diffraction) analyses were carried out on specimens before and after repetitive hammering. Metallography was carried out to observe the microstructure using an optical microscope. The hardness was tested through the Rockwell A hardness test. XRD examination was used to identify the phases formed and indications of nano-twins. The repetitive hammering process up to 350 times has succeeded in increasing hardness from 53.5 HRA to 71.6 HRA. Plastic deformation introduced by repetitive hammering produced slip bands, cross bands, wavy bands, and indication of nano-twins formation and increased the hardness.

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Chen, Lei, Ren Bo Song, Fu Qiang Yang, and Yu Pei. "Working Hardening Mechanism and Aging Treatment Behaviors of D631 Precipitation Hardening Stainless Steel Wire." Materials Science Forum 788 (April 2014): 362–66. http://dx.doi.org/10.4028/www.scientific.net/msf.788.362.

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Precipitation hardening stainless steel has the advantages of both austenitic stainless steel and martensitic stainless steel, including good corrosion resistance, excellent processability and high strength. With the evolution of microstructure and properties of semi-austenitic precipitation hardening stainless steel (D631) during drawing process and aging treatment, the working hardening behaviors, law of phase transition, dissolution and precipitation state of alloying element are investigated to gain the toughness mechanism of D631. The results show that the tensile strength increases with the increase of the reduction of area, on the contrary, the plasticity decreases gradually. The tensile strength is 1529 MPa while the reduction of area is 54%. By means of X-ray diffraction (XRD) and metallograpic observation, the content of martensite increases with the increase of deformation, and makes the higher strength and lower plasticity. The alloying element dissolved in the matrix precipitates in fine particles by aging treatment, resulting in a higher strength of 1948MPa.

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Zhang, Hong Xia, Wu Yi Chen, Xiu Zhuo Fu, and Li Xia Huang. "Temperature Measurement and Burn Mechanism of Stainless Steel 1Cr11Ni2W2MoV in Grinding." Materials Science Forum 723 (June 2012): 433–38. http://dx.doi.org/10.4028/www.scientific.net/msf.723.433.

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An experimental study was carried out to investigate the temperature measurement method and burn mechanism in the surface grinding of a stainless steel 1Cr11Ni2W2MoV with SG abrasive wheels. The temperature response at the wheel-workpiece interface was measured using a pair of thermocouple composed of the workpiece material and a single enameled constantan wire which was implanted in the workpiece. Changes in the ground surface morphology and metallography of the specimens in different grinding conditions were analyzed. Plastically deformed coating layers and micro-cracks were observed on ground surface by SEM (Scanning Electronic Microscopy) when grinding burn occurs. Grinding burn mechanism was unveiled from a metallographic point of view. When the average temperature exceeded phase alteration temperature of 1Cr11Ni2W2MoV, the original gray strip martensite structure was replaced by tempered sorbite structure, which caused a sharp reduction of the workpiece surface hardness. The results provided a theoretical and experimental basis for technical optimization in the grinding of high temperature stainless steel with high efficiency and high quality.

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Zhao, Xuehui, Wei Huang, Guoping Li, Yaorong Feng, and Jianxun Zhang. "Effect of CO2/H2S and Applied Stress on Corrosion Behavior of 15Cr Tubing in Oil Field Environment." Metals 10, no. 3 (March 23, 2020): 409. http://dx.doi.org/10.3390/met10030409.

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The corrosion behavior of a 15Cr-6Ni-2Mo martensitic stainless steel (15Cr stainless steel) in a CO2/H2S environment was investigated by conducting high-temperature/high-pressure immersion tests combined with scanning electron microscopy and metallographic microscopy. The presence of H2S decreased the corrosion resistance of the 15Cr tubing steel. The critical H2S partial pressure (PH2S) for stress corrosion cracking in the 15Cr tubing steel in the simulated oil field environment with a CO2 partial pressure of 4 MPa and an applied stress of 80% σs was identified. The 15Cr tubing steel mainly suffered uniform corrosion with no pitting and cracking when the PH2S was below 0.5 MPa. When the PH2S increased to 1 MPa and the test temperature was 150 °C, the pitting and cracking sensitivity increased. The stress corrosion cracking at a higher PH2S is attributed to the sulfide-induced brittle fracture.

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Bobir, S. V., I. Yu Prikhodko, D. V. Loshkarev, S. S. Zakharchuk, and P. V. Krot. "Analysis of the amount of retained austenite in the structure of steel rolls for sheet rolling." Fundamental and applied problems of ferrous metallurgy, no. 34 (2020): 256–64. http://dx.doi.org/10.52150/2522-9117-2020-34-256-264.

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The amount of residual austenite in martensitic roll steels is an important technological parameter of heat treatment, which affects the performance properties of the rolls. But determining its amount in roll steels is a complex and not fully solved scientific and technical problem. The aim of the work was to comparatively analyze the amount of residual austenite in the structure of alloy steel rolls by X-ray diffraction, ultrasonic methods and metallography analysis. However, the qualitative difference of microstructures in the content of the light phase - austenite, confirms the results of X-ray diffraction analysis. No correlation was found between the austenite content in the samples and their hardness. It was found that the X-ray method, based on the comparison of the intensities of the α- and γ-phase lines of iron, overestimates the value of the amount of residual austenite in some samples of roll steels. The results of the analysis of residual austenite by ultrasound rate showed better convergence. The amounts of residual austenite, calculated on the sample of stainless steel (100% γ-Fe), had reduced values (2.6-4.5%). The most accurate results on the amount of residual austenite gave the use of the established regression dependence with the selected standard (2.7-7.8%). This dependence is obtained at the speed of sound in austenite ~ 4000 m / s. It is determined that the application of the ultrasonic method allows to determine the content of residual austenite in the samples of roll steels quite quickly and accurately.

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Zhang, Huayu, Zhiheng Wei, Fengqin Xie, and Baohai Sun. "Assessment of the Properties of AISI 410 Martensitic Stainless Steel by an Eddy Current Method." Materials 12, no. 8 (April 19, 2019): 1290. http://dx.doi.org/10.3390/ma12081290.

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Based on electromagnetic theory, metallurgical characteristics can be detected by eddy current nondestructive testing technology. In this study, the relationship between the surface microstructure and the eddy current output of martensitic stainless steel AISI 410 was studied using this technology at different quenching temperatures. The mechanical properties include material hardness, microstructure types and microstructural changes after thermal treatment was evaluated. Using Vickers hardness as the surface hardness index of AISI 410 steel, the relationship between eddy current output signal, in terms of impedance and inductance, and sample surface hardness was studied and the effects of different quenching temperatures on the steel’s surface hardness was examined. In addition, the change of microstructure types of AISI 410 steel after thermal treatment was detected by the eddy current nondestructive testing method, and the results were verified by metallographic microscopy.

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Berecz, Tibor, Éva Fazakas, Enikő Réka Fábián, Péter Jenei, and János Endre Maróti. "Investigation of Thermally Induced Deterioration Processes in Cold Worked SAF 2507 Type Duplex Stainless Steel by DTA." Crystals 10, no. 10 (October 14, 2020): 937. http://dx.doi.org/10.3390/cryst10100937.

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Thermally induced deterioration processes were studied in cold worked (up to 60% deformation) SAF 2507 type super-duplex stainless steel (SDSS) by differential thermal analysis (DTA). DTA results revealed two transformations. Parent and inherited phases of these transformations were examined by other methods too, such as micro-hardness tests, optical metallography and X-ray diffraction (XRD). Finally, these transformations were identified as the formation of α’- and σ-phases. Formation of strain-induced martensite (SIM) and recrystallization were not experienced until 1000 °C, despite high degree of cold working. Activation energies of the σ-phase precipitation and α’-phase formation were determined from the Kissinger plot, through DTA measurements—they are 275 and 220 kJ/mol, respectively—in good agreement with the values found in the literature.

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Al Jabbari, Youssef S., Raymond Fournelle, Sara M. Al Taweel, and Spiros Zinelis. "Failure analysis of eleven Gates Glidden drills that fractured intraorally during post space preparation. A retrieval analysis study." Biomedical Engineering / Biomedizinische Technik 63, no. 4 (July 26, 2018): 407–12. http://dx.doi.org/10.1515/bmt-2016-0245.

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Abstract The purpose of this study was to determine the failure mechanism of clinically failed Gates Glidden (GG) drills. Eleven retrieved GG drills (sizes #1 to #3) which fractured during root canal preparation were collected and the fracture location was recorded based on macroscopic observation. All fracture surfaces were investigated by a SEM. Then the fractured parts were embedded in acrylic resin and after metallographic preparation, the microstructure and elemental composition was evaluated by SEM and EDS. The Vickers hardness (HV) of all specimens was also determined. Macroscopic examination and SEM analysis showed that the drills failed near the hand piece end by torsional fatigue with fatigue cracks initiating at several locations around the circumference and propagating toward the center. Final fracture followed by a tensile overloading at the central region of cross section. Microstructural analysis, hardness measurements and EDS show that the drills are made of a martensitic stainless steel like AISI 440C. Based on the findings of this study, clinicians should expect fatigue fracture of GG drills that have small size during root canal preparation. Selection of a more fatigue resistant stainless steel alloy and enhancing the instrument design might reduce the incidence of quasi-cleavage fracture on GG drills.

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Dineshraj, S., Mayukh Acharya, Alok Agarwal, S. Girikumar, Govind, S. C. Sharma, and Koshy M. George. "Development of Hot Isostatic Pressing Technology for Investment Cast Products." Materials Science Forum 830-831 (September 2015): 19–22. http://dx.doi.org/10.4028/www.scientific.net/msf.830-831.19.

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Hot isostatic pressing (HIPping) technology is used for healing the casting defects for aerospace applications. Castings used for aerospace applications like turbo-pumps need to meet very stringent quality requirements. Complexity of the castings used in these applications, makes it difficult to meet the quality requirements in all the areas. Defects like gas holes, shrinkages, cavities etc. may occur in few locations and need to be repaired by welding or healed by HIPping. In the present study, we attempted to simulate the defect healing capability of HIP in a systematic manner. Artificial defects were created in Austenite-Martensite grade stainless steel cast rod. These rods were then subjected to HIP prcoss cycle at 1150 °C and at a pressure of 1620 bar. Healing of the defects was ensured through X-ray radiography. Detailed microstructural analysis using optical metallography and scanning electron microscopy (SEM) with EDX was carried out before and after HIPping, to understand the defect healing mechanisms. These results are discussed in detail here.

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Impero, Filomena, Fabio Scherillo, Antonello Astarita, Kathryn A. Beamish, Michele Curioni, Antonino Squillace, and Xiao Rong Zhou. "Study of the Metallurgy of a Dissimilar Ti-6Al-4V – Stainless Steel Linear Fiction Welded Joints." Key Engineering Materials 651-653 (July 2015): 1427–32. http://dx.doi.org/10.4028/www.scientific.net/kem.651-653.1427.

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This paper deals with the investigation of the metallurgy of a dissimilar Ti-6Al-4V-stainless steel joint linear friction welded. In particular two different stainless steel were considered: AISI 304 and AISI 316. These two alloys differs in the Molybdemun content. Metallographic observations, EDS analysis and Vickers Microhardness measurements were carried out, particular attention was focused on the study of the intermetallic compounds and on the microstructures of the different zones produced by the process. As usual for solid state welding processes, three different zones can be identified: the parent material, the heat affected zone (HAZ) and the thermo-mechanical affected zone (TMAZ), furthermore a very thin joining line, rich of intermetallic compounds, was also observed. In this zone diffusive phenomena also occurred resulting in a variation of the alpha phase content on the titanium side.In the TMAZ, the bimodal microstructure of the parent material was deformed and the presence of elongated alpha grains with broken beta-phase particles was established. Moreover it was observed that in the weld region, exposure to supertransus temperatures (995°C) combined with hot-deformation working and rapid cooling after joining induced the recrystallization of a martensitic beta grain structure. Concerning the joint between Ti-6Al-4V and AISI 316 some cracks were observed within the weld line, this due to the presence of brittle intermetallics compounds in this zone. The formation of these intermetallics was promoted by the presence of Molybdenum.

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Secosan, Evelina Roxana, Relu Costel Ciubotariu, Vasile Cojocaru, Doina Frunzaverde, and Constantin Viorel Câmpian. "Study Regarding the Cavitation Erosion Behaviour and Residual Stresses of Impact Resistant Hardfacing Materials." Advanced Materials Research 1029 (September 2014): 146–51. http://dx.doi.org/10.4028/www.scientific.net/amr.1029.146.

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In the last twenty years the cavitation erosion resistance of various welded materials was subject of extensive studies. Despite these, the research field is still opened. The multitude of materials used for the fabrication of hydraulic equipment and the variety of the operating conditions in hydropower units require adapted solutions. This paper presents the investigations made on welded overlays realized using an impact resistant hardfacing alloy, recommended by manufacturers for protection against cavitation erosion. The material was characterized by metallographic investigations (light microscopy, scanning electron microscopy and EDX–analyse), Vickers micro hardness tests, residual stresses measurements carried out by the hole-drilling strain-gage method and cavitation erosion tests using the vibratory method. The results of the cavitation erosion tests were correlated to the behaviour of the martensitic stainless steel 1.4313 (grade X3CrNiMo13-4 corresponding to EN 10088-3) frequently used for the manufacturing of the hydraulic turbine components.

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Adjamskiy, Sergey, Rostislav Podolskyi, and Ganna Kononenko. "Investigation of plastic properties of AISI 316l steel by method of registration of macrolocalization fields." System technologies 4, no. 135 (April 5, 2021): 3–11. http://dx.doi.org/10.34185/1562-9945-4-135-2021-01.

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Selective laser melting is one of the modern methods of manufacturing parts in the production of machine-building equipment, a special place is occupied by complex technological processes used in the manufacture of high-load units of pneumatic-hydraulic system from heat-resistant alloys. The research was carried out on samples made of powder material - stainless steel AISI 316L martensite class. Metallographic studies showed that the density of the sample is 99.83%, the structure of the samples is a martensitic structure of equilibrium constructed tracks. Tests to determine the mechanical properties were performed in accordance with ISO 6892 on an INSTRON test machine. From the tensile diagram it was found that the yield strength was 376.56 MPa, the maximum point of temporary resistance of the sample - 615, 40 MPa 319 seconds after the start of the test. The control of the surface roughness was performed using a BioBase device. The working area of the tensile sample consisted of two areas: a roughness area of 5 μm, which accounted for 80% of the working part of the sample (zones A and Б) and 20% of the working part of the sample (zone Б), the roughness was 17 μm. According to the results of microstructure studies and studies by the method of registration of macrolocalization fields of the working zone of the samples, it was found that the destruction began from the surface of the samples from microconcentrators due to different roughness. It is established that the surface and subsurface layer with increased roughness in comparison with the main body has a smaller elongation by 10.84%. From microstructural studies of the working zone in the area of the gap, it was found that the destruction began from the surface of the samples between zones A and Б. During the research in zone A and Б, one of the concentrators of the gap was detected. As a result of the study, it was found that the destruction began with the surface of the samples and the place of change of its roughness. The mechanism of deformation of the sample from AISI 316L steel is shown, the scheme of extraction of tail sections of tracks and crack propagation in the conditions of tensile testing of the sample is constructed.

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Strobl, Susanne, Roland Haubner, and Wolfgang Scheiblechner. "New Steel Combinations Produced by the Damascus Technique." Advanced Engineering Forum 27 (April 2018): 14–21. http://dx.doi.org/10.4028/www.scientific.net/aef.27.14.

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Multilayered forged steel plates, which combine the properties of diverse steel qualities, are referred to as Damascus steels. Since the 3rd century AD blades and weapons have been produced by the Damascus technique in Europe. In this work four different steel combinations were investigated. Combining Fe with carbon steel C60 resulted in a ferritic-pearlitic microstructure. By forging two heat-treatable steels C40 and C60 martensite with an inhomogeneous carbon distribution was formed. Combining Fe with an austenitic stainless steel showed ferrite and austenite with grain boundary carbides and segregation bands. The last combination of two cold working steels K110 and K600 led to a complex microstructure with martensite, retained austenite and two special types of carbides. After metallographic preparation and using of different etchants the various microstructures were characterized by light optical microscopy and confirmed by Vicker ́s microhardness measurements. Of high interest are the interfaces and the quality of the weld between the individual steel layers. In some regions oxidation and carbon diffusion were observed.

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Rodelas, J. M., M. C. Maguire, and J. R. Michael. "Martensite Formation in the Metallographic Preparation of Austenitic Stainless Steel Welds." Microscopy and Microanalysis 19, S2 (August 2013): 1748–49. http://dx.doi.org/10.1017/s1431927613010738.

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Lopez, Juan Manuel Salgado, María Inés Alvarado, Hector Vergara Hernandez, José Trinidad Perez Quiroz, and Luis Olmos. "Failure of Stainless Steel Welds Due to Microstructural Damage Prevented by In Situ Metallography." Soldagem & Inspeção 21, no. 2 (June 2016): 137–45. http://dx.doi.org/10.1590/0104-9224/si2102.03.

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Abstract In stainless steels, microstructural damage is caused by precipitation of chromium carbides or sigma phase. These microconstituents are detrimental in stainless steel welds because they lead to weld decay. Nevertheless, they are prone to appear in the heat affected zone (HAZ) microstructure of stainless steel welds. This is particularly important for repairs of industrial components made of austenitic stainless steel. Non-destructive metallography can be applied in welding repairs of AISI 304 stainless steel components where it is difficult to ensure that no detrimental phase is present in the HAZ microstructure. The need of microstructural inspection in repairs of AISI 304 is caused because it is not possible to manufacture coupons for destructive metallography, with which the microstructure can be analyzed. In this work, it is proposed to apply in situ metallography as non-destructive testing in order to identify microstructural damage in the microstructure of AISI 304 stainless steel welds. The results of this study showed that the external surface micrographs of the weldment are representative of HAZ microstructure of the stainless steel component; because they show the presence of precipitated metallic carbides in the grain boundaries or sigma phase in the microstructure of the HAZ.

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Zhang, Zhuwu, Guangguo Pan, Yan Jiang, Song Chen, Song Zou, Wei Li, Chengwei Xu, and Jingwei Zhang. "Microstructure and Pitting Corrosion of Austenite Stainless Steel after Crack Arrest." Materials 12, no. 24 (December 4, 2019): 4025. http://dx.doi.org/10.3390/ma12244025.

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With synergy of plastic deformation near crack tip and pulse current treatment, complex phase transformation and recrystallization occur in the metallographic structure, with the austenite transforming to fine grain structure and deformation-induced martensite; but, without the plastic deformation, the phase transformation, and recrystallization it was difficult for the crack arrest process to take place only undergoing the pulse current treatment. The nano-indentation experiment showed that the phase transformation region contained the maximum residual compressive stress consisting of four parts: the plastic stress, the explosion stress, the thermal stress, and the transformation stress, which was beneficial to restrain the crack growth. However, the solidification structure and the deformation-induced martensite structure was vulnerable to pitting corrosion through scanning microelectrode technology (SMET) and pitting corrosion experiment, but the pitting corrosion resistance could be improved through the solution heat treatment.

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Tharaknath, S., H. Dineshkumar, G. Purushothaman, C. Kannadhasan, and S. Silambarasan. "Functionally Graded Martensitic Stainless Steel." IOSR Journal of Mechanical and Civil Engineering 11, no. 5 (2014): 46–49. http://dx.doi.org/10.9790/1684-11564649.

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Santos, T. F. A., and M. S. Andrade. "Internal Friction on AISI 304 Stainless Steels with Low Tensile Deformations at Temperatures between−50 and 20C." Advances in Materials Science and Engineering 2010 (2010): 1–8. http://dx.doi.org/10.1155/2010/326736.

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Austenitic stainless steels specimens were deformed by tension in temperatures in the range of−50Cto 20Cand 0.03 to 0.12 true strain, in order to obtain different volumetric fractions ofε(hexagonal close packed) andα′(body centered cubic) strain induced martensites. The morphology, distribution and volumetric fractions of the martensites were characterized by metallography and dilatometry analysis and quantified by ferrite detector measurements. The damping behavior of specimens with different volumetric fractions of martensites was studied in an inverted torsion pendulum in the 40Cto 400Crange. Theε- andα′-martensites reversion was observed in the temperature range of 50C–200Cand 500C–800C, respectively, by dilatometry. Internal friction curves in function of temperature of the deformed samples presented internal friction peaks. The first internal friction peak is related to sum of the amount ofε- andα′-martensites. For low deformations it aligns around 130Cand it is related only to theε→γreverse transformation. The peak situated around 350Cincreases with the specimen degree of deformation and is, probably, related to the presence ofα′/γinterfaces, and deformed austenite.

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Drahokoupil, Jan, Petr Haušild, Vadim Davydov, and P. Pilvin. "Phase Transformation in Austenitic Steel Induced by Plastic Deformation." Solid State Phenomena 163 (June 2010): 295–98. http://dx.doi.org/10.4028/www.scientific.net/ssp.163.295.

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Kinetics of deformation induced martensitic transformation in metastable austenitic AISI 301 steel was characterized by several techniques including classical light metallography, X-ray diffraction, neutron diffraction and electron back scattered diffraction. In order to characterize the martensitic transformation, several specimens were tensile pre-deformed to 5%, 10% and 20% of plastic deformation and compared with non-deformed state. During straining, the volume fraction of α’-martensite rapidly prevails over the volume fraction of original austenite and reach the value circa 70%.

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Liu, Jing, Ke Zhang, and Guo Liang Xie. "Effect of Cr and Ni Contents on Microstructure and Properties of High Boron Stainless Steel Composite Plate." Advanced Materials Research 535-537 (June 2012): 883–87. http://dx.doi.org/10.4028/www.scientific.net/amr.535-537.883.

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Two high boron alloyed stainless steel composite plates(HBASSCP) which have different Cr and Ni contents were prepared by composite casting and hot rolling process. By means of metallographic observation and x-ray diffraction analysis, the matrix microstructure of calding and core is ferrite and the boride phase in core material is identified as brittle Fe2B for HBASSCP which has lower Cr and Ni contents, while the matrix microstructure of calding and core and the boride phase are mainly austenite and (Fe,Cr)2B respectively for HBASSCP which has higher level of Cr and Ni contents. After solution treatment, ferrite had changed into martensite which do not have plasticity for composite plate with lower Cr and Ni contents, but the elongation and the tensile strength of HBASSCP with high contents of Ni and Cr has reached up to 12.45 % and 558MP respectively. The mechanical properties has met ASTM standard specification for borated stainless steel plate for nuclear application.

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Cukor, Goran, Graciela Šterpin-Valić, Tihana Kostadin, and Marko Fabić. "Sustainable Turning of Martensitic Stainless Steel." Transactions of FAMENA 43, no. 3 (November 22, 2019): 1–12. http://dx.doi.org/10.21278/tof.43301.

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Moustafa, I. M., N. ElBagoury, M. I. Ammar, S. A. Ibrahim, and A. A. Nofal. "Solidification mechanism of martensitic stainless steel." Ironmaking & Steelmaking 28, no. 5 (October 2001): 404–11. http://dx.doi.org/10.1179/irs.2001.28.5.404.

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Goh, G. K. L., and L. C. Lim. "Embrittlement of brazed martensitic stainless steel." Materials Science and Technology 14, no. 3 (March 1998): 251–56. http://dx.doi.org/10.1179/mst.1998.14.3.251.

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Zhang, K. Y., Y. S. Pyoun, X. J. Cao, B. Wu, and R. Murakami. "FATIGUE PROPERTIES OF SUS304 STAINLESS STEEL AFTER ULTRASONIC NANOCRYSTAL SURFACE MODIFICATION (UNSM)." International Journal of Modern Physics: Conference Series 06 (January 2012): 330–35. http://dx.doi.org/10.1142/s201019451200339x.

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The changing of materials surface properties method always was taken into improving the fatigue strength. In this paper, an ultrasonic nanocrystal surface modification(UNSM) technique was used on the SUS 304 stainless steel to form a nanostructured surface layer with different static load(70N, 90N, 110N, 130N) and the vibration strike number was about 20,000times/mm2. The untreated and different condition specimens fatigue strength was all tested by a dual-spindle rotating bending fatigue test machine. SPring-8(a large synchrotron radiation facility) was used to test the surface nanocrystallization components. The X-ray diffraction (XRD), the scanning electron microscopy (SEM), optical microscope and a micro-Vickers hardness tester (MVK-E3, Akashi) were separately used to get the surface residual stresses, fracture surface after fatigue testing, metallographic structure and the microhardness of the nanostructured surface layer. The result showed that martensite transformation took place on the surface of specimens, the surface residual stresses had only a small increase and some cracks occurred between the martensite layer and the austenite layer, but the fatigue strength of 90N improved 81%.

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Zhu, Shi Dong, Jin Ling Li, Hai Xia Ma, and Li Liu. "Pitting Resistance of Domestic Super Martensitic Stainless Steel 00Cr13Ni5Mo2." Advanced Materials Research 834-836 (October 2013): 370–73. http://dx.doi.org/10.4028/www.scientific.net/amr.834-836.370.

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Pitting resistance of super martensitic stainless steel 00Cr13Ni5Mo2 made in China has been investigated by employing electrochemical technology and chemical immersion methods. The results showed that pitting potential of super martensitic stainless steel decreased with the increasing of NaCl concentration and temperature, respectively. And corrosion rate of super martensitic stainless steel increased with the increasing of temperature. Furthermore, compared to super martensitic stainless steel made in Japan, the domestic one was better in terms of pitting potential, pitting corrosion rate and the density of the pits, but worse in terms of the depth of the pits.

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Li, J. L., C. T. Qu, S. D. Zhu, L. Liu, and Z. Q. Gao. "Pitting corrosion of super martensitic stainless steel 00Cr13Ni5Mo2." Anti-Corrosion Methods and Materials 61, no. 6 (October 28, 2014): 387–94. http://dx.doi.org/10.1108/acmm-08-2013-1293.

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Purpose – The purpose of this study was to investigate the pitting resistance and assess the critical pitting temperature (CPT) of a super martensitic stainless steel, 00Cr13Ni5Mo2, made in China, considering especially the difference in the pitting corrosion resistance between the domestic super martensitic stainless steel and an imported one. Design/methodology/approach – Potentiodynamic sweep tests were applied to investigate the effects of four NaCl concentrations (weight per cent) of 1, 3.5, 9 and 17, and four testing temperatures of 30, 50, 75 and 90°C on the pitting resistance of the domestic super martensitic stainless steel in the presence of CO2. Potentiostatic sweep tests were utilized to determine the CPT. Furthermore, chemical immersion exposures, implemented according to the appropriate standard were used to evaluate the difference in the pitting corrosion resistance between the domestic super martensitic stainless steel and an imported one. In addition, the morphology of pits was analyzed using a scanning electron microscope. Finding – The pitting potential of the domestic super martensitic stainless steel decreased with an increase in NaCl concentration and temperature in the presence of CO2. The CPT of the domestic super martensitic stainless steel measured by potentiostatic polarization was 41.16°C. Two types of typical corrosion pits, closed pits formed at 35°C and open pits formed at 50°C, were observed. Furthermore, compared to the super martensitic stainless steel made in Japan, the domestic one was better in terms of pitting potential, corrosion rate and the density of the pits, but worse in terms of the depth of the pits, which may result in a risk of corrosion perforation of tubing and casings. Originality/value – The paper highlights that chloride ions, temperature and the presence of CO2 play an important role on the pitting resistance of super martensitic stainless steel.

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Yilmaz, R., and Ali Türkyilmazoglu. "Tensile Properties of Martensitic Stainless Steel Weldments." Advanced Materials Research 23 (October 2007): 319–22. http://dx.doi.org/10.4028/www.scientific.net/amr.23.319.

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In this study, AISI 420 martensitic stainless steels were welded by GTAW (gas tungsten arc welding) using ER 316L consumables. Pure argon, argon + 25% He and argon + 5% N2 were used as shielding gases. The obtained results indicated that shielding gases have some effect on the properties of the martensitic stainless steel weldments. The use of argon+5%N2 provides the highest tensile strength values and higher microhardness profile compared to the other shielding gas composition used.

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Otsuka, Teppei, and Tetsuo Tanabe. "Hydrogen Release from Ferritic/Martensitic Stainless Steel." Fusion Science and Technology 54, no. 2 (August 2008): 541–44. http://dx.doi.org/10.13182/fst08-a1873.

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Oda, Yoshiyuki, and Nobusuke Hattori. "406 Fatigue Properties of Martensitic Stainless Steel." Proceedings of Conference of Kyushu Branch 2010.63 (2010): 131–32. http://dx.doi.org/10.1299/jsmekyushu.2010.63.131.

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Yang, J. R., T. H. Yu, and C. H. Wang. "Martensitic transformations in AISI 440C stainless steel." Materials Science and Engineering: A 438-440 (November 2006): 276–80. http://dx.doi.org/10.1016/j.msea.2006.02.098.

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Gupta, C., and J. K. Chakravartty. "Alloy softening in a martensitic stainless steel." physica status solidi (a) 206, no. 4 (April 2009): 685–90. http://dx.doi.org/10.1002/pssa.200824289.

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Selokar, Ashish, D. B. Goel, and Ujjwal Prakash. "A Comparative Study of Cavitation Erosive Behaviour of 23/8N Nitronic Steel and 13/4 Martensitic Stainless Steel." Advanced Materials Research 585 (November 2012): 554–58. http://dx.doi.org/10.4028/www.scientific.net/amr.585.554.

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Abstract: Hydroturbine blades in hydroelectric power plants are subjected to erosion. Currently these blades are made of 13/4 martensitic stainless steel (ASTM grade A743). This steel suffers from several maintenance and welding related problems. Nitronic steels are being considered as an alternative to martensitic stainless steels since they have good weldability. In present work, erosive behaviour of 13/4 Martensitic and Nitrogen alloyed austenitic stainless steel (23/8N steel) has been studied. Cavitation erosion tests were carried out in distilled water at 20 KHz frequency at constant amplitude. Microstructure of eroded surface, mechanical properties and erosion rate were characterized. It was observed that 23/8N steel possesses excellent resistance to erosion in comparison to 13/4 martensitic steels. 23/8N steel showed good hardness coupled with high tensile toughness and work hardening ability, leading to improved erosion resistance.

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Wang, W. F. "Oxygen Content and Metallography of Atomized 304L Stainless Steel Powder." Powder Metallurgy 37, no. 1 (January 1994): 33–36. http://dx.doi.org/10.1179/pom.1994.37.1.33.

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Mészáros, István. "Thermal Induced Phase Transformations in Duplex Stainless Steel." Materials Science Forum 729 (November 2012): 109–13. http://dx.doi.org/10.4028/www.scientific.net/msf.729.109.

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The aim of this work is to study the microstructural changes in 2507 type superduplex stainless steel due to heat treatments. Two series of specimens were studied. The first series were heat treated isothermally at 800 °C for different times up to 42 minutes. The second ones were heat treated isochronically for 20 minutes in the temperature range of 720-900 °C. The microstuctural changes were investigated by metallography and by magnetic tests. The first magnetization curves and the saturation magnetization loops were measured by a double yoke DC magnetometer.

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Jazaeri, Hedieh, P. Bouchard, Michael Hutchings, Mike Spindler, Abdullah Mamun, and Richard Heenan. "An Investigation into Creep Cavity Development in 316H Stainless Steel." Metals 9, no. 3 (March 12, 2019): 318. http://dx.doi.org/10.3390/met9030318.

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Creep-induced cavitation is an important failure mechanism in steel components operating at high temperature. Robust techniques are required to observe and quantify creep cavitation. In this paper, the use of two complementary analysis techniques: small-angle neutron scattering (SANS), and quantitative metallography, using scanning electron microscopy (SEM), is reported. The development of creep cavities that is accumulated under uniaxial load has been studied as a function of creep strain and life fraction, by carrying out interrupted tests on two sets of creep test specimens that are prepared from a Type-316H austenitic stainless steel reactor component. In order to examine the effects of pre-strain on creep damage formation, one set of specimens was subjected to a plastic pre-strain of 8%, and the other set had no pre-strain. Each set of specimens was subjected to different loading and temperature conditions, representative of those of current and future power plant operation. Cavities of up to 300 nm in size are quantified by using SANS, and their size distribution, as a function of determined creep strain. Cavitation increases significantly as creep strain increases throughout creep life. These results are confirmed by quantitative metallography analysis.

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Kumar, Anish, B. Sasi, Govind K. Sharma, B. Purnachandra Rao, and T. Jayakumar. "Nondestructive Evaluation of Austenitic Stainless Steel Welds." Advanced Materials Research 794 (September 2013): 366–74. http://dx.doi.org/10.4028/www.scientific.net/amr.794.366.

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The paper presents advanced ultrasonic and eddy current NDE techniques developed in the authors laboratory for nondestructive evaluation of austenitic stainless steel welds. The paper discusses the performance and comparison of 2D discrete wavelet transform (DWT) and de-noising methods applied on eddy current images obtained from stainless steel weld pad with machined longitudinal notches and a systematic approach for eddy current defect characterisation in weld pads by neural network. The simulation and experimental results on the effect of elastic anisotropy on ultrasonic phased array inspection in austenitic stainless steel weld are also discussed. A guided wave based ultrasonic method developed for detection of defects in stainless steel welds and its validation with complimentary techniques such as radiography and in-situ metallography are also presented.

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Karadas, Riza, Ozgur Celik, and Huseyin Cimenoglu. "Low Temperature Nitriding of a Martensitic Stainless Steel." Defect and Diffusion Forum 312-315 (April 2011): 994–99. http://dx.doi.org/10.4028/www.scientific.net/ddf.312-315.994.

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Nitriding is as an effective technique applied for many years to improve the surface hardness and wear resistance of low carbon and tool steels [1]. In the case of stainless steels, increase of surface hardness and wear resistance accompany by a drop in corrosion resistance due to the precipitation of CrN. In this respect, many attempts have been made to modify the surfaces of austenitic stainless steels to increase their surface hardness and wear resistance without scarifying the corrosion resistance [2-6]. It is finally concluded that, nitriding at temperatures lower than conventional nitriding process (which is generally about 550°C) has potentiality to produce a nitrogen expanded austenite (also known as S-phase), on the surface without formation of CrN. Due to the superb properties of the S-phase, the low temperature nitrided austenitic stainless steels exhibit very high surface hardness, a good wear resistance, and more importantly, an excellent corrosion resistance. Recently some attempts have been made to apply low temperature nitriding to martensitic stainless steels, which are widely used in the industries of medicine, food, mold and other civil areas [7-9]. In these works, where nitriding has been conducted by plasma processes, superior surface hardness, along with excellent wear and corrosion resistances have been reported for AISI 410 and AISI 420 grade martensitic stainless steels. This work focuses on low temperature gas nitriding of AISI 420 grade martensitic stainless steel in a fluidized bed reactor. In this respect the microstructures, phase compositions, hardness, wear and corrosion behaviours of the original and nitrided martensitic stainless steels have been compared.

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Lee, Chi-Seung, Byung-Moon Yoo, Myung-Hyun Kim, and Jae-Myung Lee. "Viscoplastic damage model for austenitic stainless steel and its application to the crack propagation problem at cryogenic temperatures." International Journal of Damage Mechanics 22, no. 1 (March 5, 2012): 95–115. http://dx.doi.org/10.1177/1056789511434816.

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Austenitic stainless steel, or the so-called transformation-induced plasticity steel, exhibits high nonlinearity when strain-induced martensitic transformation occurs at various strain rates and temperatures, especially at cryogenic temperatures and high strain rates. The strong hardening, which is caused by the strain-induced martensitic transformation, is an important property of austenitic stainless steel. In this work, a viscoplastic model that considers the martensitic phase transformation of austenitic stainless steel is introduced in order to identify nonlinear mechanics, including the strong hardening phenomenon. In addition, the well-known damage mechanics approach is also used to predict material fractures under arbitrary loads. In order to apply the developed viscoplastic model to failures at the structural level, the crack propagation characteristics of an austenitic stainless steel plate are also predicted on the basis of the ABAQUS user-defined subroutine UMAT. In order to demonstrate the feasibility of the model, the simulation results are compared with the uniaxial tensile and crack propagation test results for the austenitic stainless steel plate.

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Tosapolporn, Pornpibunsompop. "Characterization of Welded Austenitic Stainless Steel Precipitation during Elevated Temperature." Applied Mechanics and Materials 446-447 (November 2013): 288–90. http://dx.doi.org/10.4028/www.scientific.net/amm.446-447.288.

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The precipitation characterization of SUS 310S weld metal was investigated by TG/DSC and metallography technique. SMAW was selected for this study and then cut with water jet avoiding thermal effect. Austenitic is the main microstructure of weld metal because of high Creqv./Nieqv. Precipitation launched higher both %mass change and heat consumed as well as the precipitation temperature was around 800 degree Celsius.

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Kusmoko, Alain, D. Dunne, H. Li, and D. Nolan. "Laser Cladding of Stainless Steel Substrates with Stellite 6." Materials Science Forum 773-774 (November 2013): 573–89. http://dx.doi.org/10.4028/www.scientific.net/msf.773-774.573.

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Stellite 6 coatings were produced using laser cladding of two different steel substrates (martensitic and austenitic stainless steels). The chemical composition and microstructure of these coatings were characterized by atomic absorption spectroscopy, optical microscopy and scanning electron microscopy. The microhardness of the coatings was measured and the wear mechanism of the coatings was examined using a pin-on-plate (reciprocating) wear testing machine. The results showed less cracking and pore development for Stellite 6 coatings applied to the martensitic stainless steel (SS) substrate. The wear test results showed that the weight loss for the coating on martensitic SS was significantly lower than for the austenitic SS substrate. It is concluded that the higher hardness of the coating on the martensitic SS, together with the harder and more rigid substrate increase the wear resistance of the Stellite 6 coating.

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42

Lin, Yu Li, Chih Chung Lin, An Chun Liu, and Hong Jen Lai. "TEM Microstructural Investigation of 0.63C-12.7Cr Martensitic Stainless Steel during Various Tempering Treatments." Advanced Materials Research 79-82 (August 2009): 2107–10. http://dx.doi.org/10.4028/www.scientific.net/amr.79-82.2107.

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Microstructure of 0.63C-12.7Cr martensitic stainless steel during various tempering treatments was investigated in this study. Results demonstrate that finely distributed primary carbides were observed on 0.63C-12.7Cr martensitic stainless steel. The matrix phase of 0.63C-12.7Cr martensitic stainless steel when tempered below 500 °C was identified as martensite. However, the matrix structure when tempered at 500 °C and 600 °C was found containing of both ferrite and martensite. On carbide particles, mixed of M7C3 and M23C6 particles were observed on all specimens when tempered at 200-600 °C. The amount of M7C3 carbides was found decreased as the tempered temperature was increased.

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Zhang, Jian Bin, Dong Mei Yu, Shao Rui Niu, and Gen Shun Ji. "Flow Behavior of 430 Ferritic Stainless Steel at Elevated Temperatures." Advanced Materials Research 721 (July 2013): 77–81. http://dx.doi.org/10.4028/www.scientific.net/amr.721.77.

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The tensile test of casting ferritic stainless steel was conducted on SHIMADZU AG-10 at different temperatures of 300, 500, 600, 700, 800, and 950°C, respectively. The engineering stress-strain curves with the thermal deformation at the different temperatures, the tensile strength and elongation curves were obtained. Metallographic test samples were prepared and the morphology of deforming zone was observed by optical microscopy. The experimental results showed that the tensile strength of the test samples decreased with increasing temperature. From 300 to 500°C, the work hardening occurred and the tensile strength increased with increasing engineering strain. The softening occurred and the tensile strength decreased with increasing engineering strain at temperatures from 600 to 950°C. The strength of 430 stainless steel decreased, and the plasticity increased with the increase in temperature. The fractures were basically intergranular fractures within the range of 300~950°C. A transition occurred to the form of fracture from the ductile to the brittle, which might be related to the nitrogen atom in the 430. Grain deformation along specimen tensile direction concentrated in the necking region, where appeared banded structure in martensite. The organization at the edge of the sample was fine, while the organization at the central region was coarser.

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44

Oktadinata, Herry, and Adi Ganda Putra. "MICROSTRUCTURE AND HARDNESS PROFILE OF DISSIMILAR LAP JOINT OF TYPE 304 STAINLESS STEEL TO SS400 CARBON STEEL." Metal Indonesia 41, no. 2 (December 31, 2019): 46. http://dx.doi.org/10.32423/jmi.2019.v41.47-54.

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Dissimilar metal welds between austenitic stainless steel and carbon steel are commonly used in oil and gas industries for certain reasons. The objective of this research is to asses the effect of filler metal and shielding gas on the microstructure and hardness of dissimilar lap joint of type 304 austenitic stainless steel to JIS SS400 low carbon steel. For the purpose of this investigation, the weldments were produced using flux-cored arc welding (FCAW). Three types of filler metals (E316L, E309L and E308L) and two different gas compositions (100%CO2 and 90%Ar+10%CO2) were selected to be used. Each of the weldments were analyzed on the microstructure characteristic and hardness profile of base metal (BM), heat affected zone (HAZ) and weld metal (WM) using optical microscope and microhardness Vickers. The metallographic examination revealed HAZ-SS400 contains martensites. Both HAZ-304 and WM show austenitic microstructure, with columnar and cellular sub-structures present at WM. The hardness profile of HAZ-304 is higher than BM-304, it may be attributed to the presence of the fine grains in HAZ-304 due to high temperature during welding. The hardness profile of WM-E309L exhibited the hardness from HAZ to WM tend to decrease linearly, while WM-E316L and WM-E308L showed the hardness from HAZ to WM also decreased but drastically dropped at fusion line (FL). The welds using E309L offer the best result in the point of view homogeneity of the hardness profile.

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45

Song, Ren Bo, Yu Pei, Yi Su Jia, Zhe Gao, Yang Xu, and Peng Deng. "Effect of Different Deformation on Microstructures and Properties in 304HC Austenitic Stainless Steel Wire." Materials Science Forum 788 (April 2014): 323–28. http://dx.doi.org/10.4028/www.scientific.net/msf.788.323.

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Two different components of Φ5.5mm 304HC stainless steel wires were drawn at room temperature. After the drawing tests, hard wires of Φ4.5mm, Φ3.8mm and Φ3.45mm were obtained. During the process of drawing, the stacking fault energy of the metastable austenitic stainless steel was low, which have caused strain-induced martensitic transformation. By XRD, TEM, martensitic volume fraction measurement, etc., the results show that the strain-induced martensitic transformations of the two different components were different significantly. When the deformation amount was controlled at 33% or less, a small amount of γ → α ' martensitic transformations of two steels has occurred. While the deformation arrived at 52% or more, a large amount of γ → α ' martensitic transformation has occurred. The stainless steel which has a higher Cu content will have a lower martensite content, which results from the reason that Cu has a strong inhibitory effect on the martensitic formation. In addition, the martensitic transformation can also influence properties. With the accumulation of strain, deformation mainly occurs in martensitic structure, which reduces the plasticity.

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Korneev, A. E., A. A. Korneev, A. S. Gugenko, and E. M. Simich-Lafitskaya. "Study of the effect of the deformation martensite on the corrosion resistance of NPP equipment and pipelines made of austenitic steels." Industrial laboratory. Diagnostics of materials 87, no. 3 (March 21, 2021): 29–34. http://dx.doi.org/10.26896/1028-6861-2021-87-3-29-34.

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Austenitic stainless steels are widely used in nuclear and thermal power engineering due to their high mechanical, corrosion and technological properties. We present the results of studying the effect of deformation martensite on the corrosion resistance of chromium-nickel steels of the austenitic class. Samples of heat exchange tubes of steam generators, tube bends, plates (constituents of steam turbines), safety valves used in NPP equipment were studied. The tests were carried out using metallographic, X-ray diffraction, atomic emission and atomic absorption spectral analyses. Electron microscopy was used to determine the content of the ferrite phase. It is shown that irregular dark gray spots located along a line parallel to the sample axis contain iron oxides. The appearance of such defects observed only on the outer surface of the products is attributed to the technology of their manufacture. It is also shown that severe plastic deformation which occurs during production or operation leads to formation of the deformation martensite which is subject to corrosion at this the corrosion cracking is accompanied by stress. The absence of δ-ferrite in the metal of samples is also revealed. The deformation martensite formed during operation of the product at the point of contact with a harder material leads to appearance of a large number of microcracks, which develop according to the fatigue mechanism under cyclic loading. The results obtained can be used to assess the probability of the formation of deformation martensite in chromium-nickel austenitic steels.

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47

Lin, Yu Li, Chih Chung Lin, Tsung Hsien Tsai, and Hong Jen Lai. "Microstructure and Mechanical Properties of 0.63C-12.7Cr Martensitic Stainless Steel during Various Tempering Treatments." Advanced Materials Research 47-50 (June 2008): 274–77. http://dx.doi.org/10.4028/www.scientific.net/amr.47-50.274.

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In this study, the microstructure and mechanical properties of 0.63C-12.7Cr martensitic stainless steel during various tempering treatments were investigated. Experimental results demonstrate that finely distributed primary carbides can be observed in 0.63C-12.7Cr martensitic stainless steel. It was also found that the measured hardness of 0.63C-12.7Cr martensitic stainless steel after 300°C tempered treatment for 60 minutes can still reach to 677Hv. The variation of measured hardness was found not significant during tempering treatments (200°C-500°C). Moreover, owing to lower concentration of C and Cr, the matensitic transformation temperature Ms can be increased to 96.4°C comparing to -127°C of SUS440C materials.

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Xu, Peng, Heng Ju, Cheng Xin Lin, and Chao Yu Zhou. "Coating of Fe-Mn-Si Shape Memory Materials on AISI 304 Stainless Steel by Laser Cladding Method." Applied Mechanics and Materials 477-478 (December 2013): 1393–96. http://dx.doi.org/10.4028/www.scientific.net/amm.477-478.1393.

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Using laser cladding method, the coating of Fe-Mn-Si shape memory materials (SMM) was prepared on the surface of AISI 304 stainless steel. The microstructure and microhardness of SMM laser cladding coating were measured by using a metallographic microscope and a scanning electron microscope, respectively. The phase composition was determined by X-ray diffraction. The wear resistance was evaluated on a high speed reciprocating friction tester. The results show that microhardness of the SMM coating is about Hv263, higher than that of the substrate (Hv225); the SMM coating is composed of ε-martensite and γ-austenite phases; the average friction coefficient of the substrate and SMM coating is about 0.85 and 0.71; the SMM laser cladding coating is of excellent wear resistance validated by friction coefficient, worn-out appearance and wear loss.

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Abd El-Hady, Mohamed. "Tempering of AISI 416 Martensitic Stainless Steel.(Dept.M)." MEJ. Mansoura Engineering Journal 20, no. 1 (April 3, 2021): 115–29. http://dx.doi.org/10.21608/bfemu.2021.160765.

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Chen, Wei, J. H. Luan, Lianyong Xu, Yongdian Han, Lei Zhao, Ji-Jung Kai, Bo Xiao, and Hongyang Jing. "Reversed austenite in additively manufactured martensitic stainless steel." Materials Science and Engineering: A 834 (February 2022): 142597. http://dx.doi.org/10.1016/j.msea.2022.142597.

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Journal articles on the topic 'Martensitic stainless steel Metallography'

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