Effects of Craddition on Charpy impact energy in austenitic 0.45C-24Mn-(0,3,6)Cr steels

作     者：Seok Gyu Lee Bohee Kim Min Cheol Jo Kyeong-Min Kim Junghoon Lee Jinho Bae Byeong-Joo Lee Seok Su Sohn Sunghak Lee Seok Gyu Lee;Bohee Kim;Min Cheol Jo;Kyeong-Min Kim;Junghoon Lee;Jinho Bae;Byeong-Joo Lee;Seok Su Sohn;Sunghak Lee

作者机构：Center for Advanced Aerospace MaterialsPohang University of Science and TechnologyPohang37673South Korea Steel Products Design TeamHyundai SteelDangjin31779South Korea Steel Products Research Group 1Technical Research LaboratoriesPOSCOGwangyang57807South Korea Department of Materials Science and EngineeringKorea UniversitySeoul02841South Korea 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2020年第47卷第15期

页      面：21-30页

核心收录：

学科分类：08[工学] 0817[工学-化学工程与技术] 0806[工学-冶金工程] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 0703[理学-化学] 0802[工学-机械工程] 0801[工学-力学（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：supported financially by the Korea University Grant for the eighth author, the Ministry of Knowledge Economy (No. 10044574-2013-45) Brain Korea 21 Plus Project for Center for Creative Industrial materials Korea Institute for Advancement of Technology (KIAT) grant funded by the Korea Government (MOTIE) (No. P0002020, The Competency Development Program for Industry Specialist)。 

主　　题：Austenitic high-Mn steels Charpy impact energy Split Hopkinson pressure bar Twinning induced plasticity(TWIP) Transformation induced plasticity(TRIP) Stacking fault energy(SFE) 

摘      要：Effects of Cr addition(0,3,and 6 wt%) on Charpy impact properties of Fe-C-Mn-Cr-based steels were studied by conducting dynamic compression tests at room and cryogenic temperatures.At room temperature,deformation mechanisms of Charpy impacted specimens were observed as twinning induced plasticity(TWIP) without any transfo rmation induced plasticity(TRIP) in all the steels.At cryogenic temperature,many twins were populated in the Cr-added steels,but,interestingly,fine ε-martensite was found in the OCr steel,satisfying the Shoji-Nishiyama(S-N) orientation relationship,{111}γ//{0002}ε and γ//ε.Even though the cryogenic-temperature staking fault energies(SFEs) of the three steel were situated in the TWIP regime,the martensitic transformation was induced by Mn-and Cr-segregated bands.In the OCr steel,SFEs of low-(Mn,Cr) bands lay between the TWIP and TRIP regimes which were sensitively affected by a small change of SFE.The dynamic compressive test results well showed the relation between segregation bands and the SFEs.Effects of Cr were known as not only increasing the SFE but also promoting the carbide precipitation.In order to identify the possibility of carbide formation,a precipitation kinetics simulation was conducted,and the predicted fractions of precipitated M23C6 were negligible,0.4-1.1×10-5,even at the low cooling rate of 10℃/s.