文献类型：期刊文献

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

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

机构：[1]Northeastern Univ, State Key Lab Rolling & Automation, Shenyang 110819, Peoples R China;[2]Hangzhou City Univ, Adv Mat Addit Mfg Innovat Res Ctr, Hangzhou 310015, Peoples R China;[3]Guangdong Ocean Univ, Sch Mech & Power Engn, Zhanjiang 524000, Peoples R China;[4]Univ Hong Kong, Dept Mech Engn, Hong Kong 999077, Peoples R China

年份：2024

卷号：198

起止页码：231

外文期刊名：JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY

收录：SCI-EXPANDED(收录号：WOS:001238666300001)、、EI(收录号：20241816015337)、Scopus(收录号：2-s2.0-85191655445)、WOS

基金：The research was financially supported by the National Natural Science Foundation of China (No. 52201112 , U22A20106 , and 52071066) , and the China Postdoctoral Science Foundation (2022M710627) . Mingxin Huang acknowledges the support from the Innovation and Technology Fund (MHP-064-20) . Jinliang Wang acknowledges the support from the National Natural Science Foundation of China (No. 52101133) .

语种：英文

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

外文摘要：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 (E-i) 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 degrees C). Contrary to the crack propagation energy (E-p), the E-i has a weak correlation with the volume fraction of alpha '-martensite but a strong correlation with the martensitic transformation rate. Also contrary to the traditional viewpoint of E-p considering epsilon-martensite as a detrimental phase, a high volume fraction of epsilon-martensite turns out to be beneficial to the increase of E-i, thereby enhancing impact toughness. As such, an optimal value (15 mJ/m(2)) for the stacking fault energy (SFE), which dictates the gamma ->epsilon ->alpha ' transformation sequence, is given as a new design guideline for enhancing the E-i 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. (c) 2024 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.