文献类型：期刊文献

中文题名：Optimizing crack initiation energy in austenitic steel via controlled martensitic transformation

作者：Minghao Huang[1,2];Lingyu Wang[1];Chenchong Wang[1];Yizhuang Li[1];Jinliang Wang[3];Jiahua Yuan[1];Jun Hu[1];Mingxin Huang[4];Wei Xu[1]

机构：[1]State Key Laboratory of Rolling and Automation,Northeastern University,Shenyang 110819,China;[2]Advanced Materials Additive Manufacturing Innovation Research Center,Hangzhou City University,Hangzhou 310015,China;[3]School of Mechanical and Power Engineering,Guangdong Ocean University,Zhanjiang 524000,China;[4]Department of Mechanical Engineering,The University of Hong Kong,Hong Kong 999077,China

年份：2024

卷号：198

期号：31

起止页码：231

中文期刊名：Journal of Materials Science & Technology

外文期刊名：材料科学技术(英文版)

收录：CSCD2023_2024、CSCD

基金：supported by the National Natural Science Foundation of China(No.52201112,U22A20106,and 52071066);the China Postdoctoral Science Foundation(2022M710627);the support from the Innovation and Technology Fund(MHP-064-20);the support from the National Natural Science Foundation of China(No.52101133).

语种：英文

中文关键词：Charpy impact energy;Crack initiation energy;Deformation induced martensitic transformation;Stacking fault energy;Austenitic steels

中文摘要：Although the seemingly negative effect of deformation-induced martensite(DIM)volume fraction on the impact toughness of austenitic steels has been well documented,it relies mostly on analyzing crack propagation without explicitly considering the crack initiation process which,however,plays a crucial role in these ductile alloys.The dependence of crack initiation energy(Ei)on martensitic transformation mechanisms is still ambiguous,inhibiting the precise design of damage-tolerant and ductile alloys.Here,we explore the temperature-dependent crack initiation energy of a SUS321 stainless steel at various temperatures(25,-50,and-196℃).Contrary to the crack propagation energy(Ep),the Ei has a weak correlation with the volume fraction ofα′-martensite but a strong correlation with the martensitic transformation rate.Also contrary to the traditional viewpoint of Ep consideringε-martensite as a detrimental phase,a high volume fraction ofε-martensite turns out to be beneficial to the increase of Ei,thereby enhancing impact toughness.As such,an optimal value(15 mJ/m^(2))for the stacking fault energy(SFE),which dictates theγ→ε→α′transformation sequence,is given as a new design guideline for enhancing the Ei and consequently the impact toughness of ductile steels.The generality of this guideline is further validated in multiple austenitic steels with different compositions and grain sizes.