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Analysis of the strain induced martensitic transformation in austenitic steel subjected to dynamic perforation  [cached]
Rodríguez-Martínez J.A.,Rusinek A.,Pesci R.,Zaera R.
EPJ Web of Conferences , 2012, DOI: 10.1051/epjconf/20122604036
Abstract: An experimental and numerical analysis on the martensitic transformation in AISI 304 steel sheets subjected to perforation by conical and hemispherical projectiles is reported. Two target thicknesses are considered, 0.5 and 1.0 mm, and impact velocities range from 35 to 200 m/s. The perforation mechanisms are identified and the effect of the projectile nose-shape on the ability of the target for energy absorption is evaluated. Martensite has been detected in all the impacted samples and the role played by the projectile nose-shape on the transformation is highlighted. A 3D model implemented in ABAQUS/Explicit allowed to simulate the perforation tests. The material is defined through a constitutive description developed by the authors to describe the strain induced martensitic transformation taking place in metastable austenitic steels at high strain rates. The numerical results are compared with the experimental evidence and satisfactory matching is obtained. The numerical model succeeds in describing the perforation mechanisms associated to each projectile-target configuration analysed.
Effects of Plastic Deformation and Stresses on Dilatation during the Martensitic Transformation in a B-bearing Steel

MCSomani,LPKarjalainen,MOldenburg,MEriksson,

材料科学技术学报 , 2001,
Abstract: To provide data for improved modelling of the behaviour of steel components in a simultaneous forming and quenching process, the effects of plastic deformation and stresses on dilatation during the martensitic transformation in a B-bearing steel were investigated. It was found that plastic deformation of austenite at high temperatures enhances ferrite formation significantly, and consequently the dilatation decreases markedly even at a cooling rate of 280 degreesC/s. The created ferritic-martensitic microstructure possesses clearly lower hardness and strength than the martensitic structure. Elastic stresses cause the preferred orientation in martensite to be formed so that diametric dilatation can increase by nearly 200% under axial compression.
Martensitic Transformation in Ultrafine-Grained Stainless Steel AISI 304L Under Monotonic and Cyclic Loading  [PDF]
Andreas B?hner,Thomas Niendorf,Doris Amberger,Heinz Werner H?ppel,Mathias G?ken,Hans Jürgen Maier
Metals , 2012, DOI: 10.3390/met2010056
Abstract: The monotonic and cyclic deformation behavior of ultrafine-grained metastable austenitic steel AISI 304L, produced by severe plastic deformation, was investigated. Under monotonic loading, the martensitic phase transformation in the ultrafine-grained state is strongly favored. Under cyclic loading, the martensitic transformation behavior is similar to the coarse-grained condition, but the cyclic stress response is three times larger for the ultrafine-grained condition.
MORPHOLOGY OF MARTENSITE IN 7CrSiMnMoV STEEL AND ITS STRENGTH-TOUGHNESS
WANG Ruixiang GU Nanju YIN Fuxing Hebei Institute of Technology,Tianjin,China,
WANG Ruixiang GU Nanju YIN Fuxing Hebei Institute of Technology
,Tianjin,China

金属学报(英文版) , 1991,
Abstract: The morphology and substructure of martensites in 7CrSMnMoV steel were observed under optical or electron microscope,and martensitic transformation with its morphology was also analysed.In the normally quenched steel three types of martensites are found,including the wide lath one of dislocation substructure formed preferentially along grain boundaries,the thinner inner laths and the twinning martensite plate in interior of grain.Therefore,an at- tempt was made to substitute lower bainite,formed by short-term isothermal quenching.for intergranular martensite,it is believed that the morphology would be very influential to the stength-toughness of the steel.
MORPHOLOGY OF MARTENSITE IN 7CrSiMnMoV STEEL AND ITS STRENGTH-TOUGHNESS
7CrSiMnMoV钢的马氏体形态及其强韧性研究

WANG Ruixiang,GU Nanju,YIN Fuxing Hebei Institute of Technology,Tianjin,
王瑞祥
,谷南驹,殷福星

金属学报 , 1991,
Abstract: The morphology and substructure of martensites in 7CrSiMnMoV steel were observed under optical or electron microscope, and martensitic transformation with its morphology was also analysed. In the normally quenched steel three types of martensites are found, including the wide lath one of dislocation substructure form- ed preferentially along grain boundaries, the thinner inner laths and the twinning martensite plate in interior of grain. Therefore, an attempt was made to substitute lower bainite, formed by short-term isothermal quenching, for intergranular marten- site, it is believed that the morphology would be very influential to the strength- toughness of the steel.
Efeito do gradiente de martensita induzida por deforma??o sobre o fen?meno de delayed cracking em a?os inoxidáveis austeníticos
Santos, Marta Ribeiro dos;Alves, Hélio José Batista;Lopes, Robson Guimar?es;Gonzalez, Berenice Mendon?a;
Rem: Revista Escola de Minas , 2007, DOI: 10.1590/S0370-44672007000100026
Abstract: the main objective of this work was to study the delayed cracking phenomenon in metastable austenitic stainless steels when they were significantly deformed by deep drawing. during the forming operations, the austenite of these steels has transformed substantially to martensite. the volume fraction of this phase has changed with the cup height and chemical composition. copper is an alloying element able to turn the steels less prone to the cracking by inhibiting the martensitic transformation. martensite gradients throughout the drawn and redrawn cups wall were determined for one conventional and a copper-added austenitic stainless steel and their effects on the delayed cracking phenomenon were evaluated.
MORPHOLOGY AND SUBSTRUCTURE OF JUJUBE-STONE-LIKE MARTENSITE IN ULTRAHIGH CARBON STEEL
超高碳钢中枣核状马氏体形态及亚结构

ZHANG Zhanling School of Materials Science,Engineering,Henan University of Science,Technology,Luoyang LIU Yongning,YU Guang,ZHU Jiewu,HE Tao State Key Laboratory for Mechanical Behavior of Materials,Xi''an Jiaotong University,Xi''an,
张占领
,柳永宁,于光,朱杰武,何涛

金属学报 , 2009,
Abstract: In the martensitic transformation of an ultrahigh carbon steel (UHCS) containing 1.58%C, a kind of jujube-stone-like martensite has been observed in addition to lath and twinning martensites. The substructure of the jujube-stone-like martensite is high density dislocation with 1013/cm2 and no twin has been found. Theoretical analysis based on a disc-like martensite grain shows that the strain energy is not relative to the critical thickness of the disc (2t0*) but relative to the critical diameter of the disc (2r0*), and the critical nucleation energy ΔG* is inversely related to the square of the critical aspect ratio, t0*/r0*, of martensitic grains. When t0*/r0*<1, martensitic nucleus is disc shape, t0*/r0*>1, the nucleus is jujube--stone--like and t0*/r0*>>1, the nucleus is rod shape.
RESEARCH ASPECTS OF TRANSFORMATION AND APPLICATION OF BAINITE AND MARTENSITE
贝氏体与马氏体相变及应用的研究

FANG Hongsheng,YANG Zhigang,WANG Jiajun,ZHENG Yankang,
方鸿生
,杨志刚,王家军,郑燕康

金属学报 , 1996,
Abstract: The key and most recent research results on bainite transformation obtained by Phase Transformation and Multi-Phase New Materials Research Group of Tsinghua University have been generalized in this paper,including the objective and popular existence of three-dimensional super and nanometer scale ledges, the mobility of ledge risers, internal ultra fine structure of bainitic plates, the characteristic and nature of bainitic surface reliefs, the source and formation models of bainitic carbide, STM and AFM studies of martensitic surface reliefs, etc. The sympathetic nucleation and ledgewise growth (SNLG) formation mechanism of bainite has been further described, and applied to interpret the multi-layer complicated substructure. Also the industrial application of air-cooled bainitic/martensitic duplex phase steel has been related.Correspondent: WANG Jiajun, associate professor, (Department of Materials Science and Engineering,Tsinghua University, Beijing 100084)
SOME ASPECTS OF PROGRESS AND PERSPECTIVE IN MARTENSITIC TRANSFORMATION
XU Zuyao Shanghai Jiaotong University,Shanghai,China,
T.Y.Hsu

金属学报(英文版) , 1991,
Abstract: Progress and perspective in martensitic transformations are described,including the definition and the thermodynamics of martensitic transformatian,the effect of austenite state on martensitic transformation,kinetics,nucleation and growth the as well as the crystallography of martensitic transformation.
STRAIN INDUCED MARTENSITIC TRANSFORMATION IN FATIGUE CRACK TIP ZONE FOR AN ULTRA-HIGH STRENGTH STEEL
超高强度钢疲劳塑性区内的应变诱发马氏体相变

GAO Huilin,TAN Yuxu,Xi'an Jiaotong UniversityWANG Xiaotian Professor,
高惠临
,谈育煦,王笑天

金属学报 , 1988,
Abstract: The retained austenite at the fatigue plastic zone in a low-carbon mar-rensitic ultra-high strength steel transforms to martensite was observed. The influenceof this strain induced transformation on the fatigue behavior of the steel has beendiscussed.
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