文献类型：期刊文献

英文题名：Response of hydrogen diffusion and hydrogen embrittlement to Cu addition in low carbon low alloy steel

作者：Wang, Jinliang[1];Xu, Ning[2];Wu, Tong[1];Xi, Xiaohui[1];Wang, Gui[1];Chen, Liqing[2]

机构：[1]Guangdong Ocean Univ, Sch Mech Engn, Zhanjiang 524088, Peoples R China;[2]Northeastern Univ, State Key Lab Rolling & Automation, Shenyang 110819, Peoples R China

年份：2023

卷号：195

外文期刊名：MATERIALS CHARACTERIZATION

收录：SCI-EXPANDED(收录号：WOS:000891385500004)、、EI(收录号：20224913208045)、Scopus(收录号：2-s2.0-85143128901)、WOS

基金：Acknowledgements This work is supported by the National Natural Science Foundation of China (Grant No: 52101133) , Guangdong Basic and Applied Basic Research Foundation (Grant No: 2021A1515110581) . the Science and Technology Projects of Zhanjiang (Grant No: 2021E05003 and 211019116630767) and the program for scientific research start-up funds of Guangdong Ocean University.

语种：英文

外文关键词：Low carbon low alloy steel; Retained austenite; Cu-rich precipitate; Hydrogen embrittlement; Slow-strain-rate tensile (SSRT) test; Impact test; Hydrogen permeation test

外文摘要：Hydrogen embrittlement (HE) has arisen as a critical issue for the development of high strength steel. The austenite and Cu-rich precipitates can provide stable trapping sites for diffusible hydrogen, and thus improved the resistance to HE. But the research on the synergistic effect of Cu and austenite on HE in low carbon low alloy steel has not been actively reported. In this study, four steels with varying Cu addition (0-3 wt%) were fabricated, and their resistance to HE was evaluated. The role of Cu addition was investigated by the ductile-brittle transition temperature (DBTT) value obtained from Charpy impact test and the loss of elongation measured from slow -strain-rate tensile (SSRT) test after hydrogen charging. Also, the hydrogen diffusivity and concentration were evaluated by electrochemical hydrogen permeation test. Cu addition resulted in a first decrease and subsequent increase of effective diffusion coefficient (Deff), elongation loss and DBTT, and the minimum value was achieved in steel with 1.5 wt% Cu addition, indicating a higher resistance to HE. The unraveled mechanism was that Cu addition increased the content of retained austenite, which impeded the diffusion of hydrogen during defor-mation. But the stability of retained austenite decreased when the content of retained austenite reached a high value, which led to martensitic transformation and accordingly increased HE susceptibility. Moreover, Cu addition promoted the formation of Cu-rich precipitates in which Cu cluster/bcc Cu-rich precipitate coherent/ semi-coherent with matrix can be strong trapping sites for hydrogen, and fcc Cu-rich precipitate acted as weak trapping sites for hydrogen. In addition, a higher density of dislocations was found in the steel with 1.5 wt % Cu addition, which may contribute to lower Deff and higher density of hydrogen traps (NT). The present work suggested that Cu addition can enhance the resistance to HE during tensile and impact processes for the design of high strength steel.