Effect of Dynamic Strain Aging on Hardness in the Heat-Affected Zone of SUS316 Steel Welds  

作　　者：Lina Yu Kazutoshi Nishimoto Kazuyoshi Saida 

机构地区：[1]Graduate School of Engineering,Osaka University,Osaka 565-0871,Japan

出　　处：《材料科学与工程（中英文A版）》2023年第1期13-25,共13页Journal of Materials Science and Engineering A

基　　金：supported by Kansai Electric Power Co.,Inc.,Japan.The authors gratefully acknowledge the assistance of Mr.Ikumi Asai,who holds a Master’s degree from the Graduate School of Engineering,Osaka University,Japan.

摘　　要：DSA(dynamic strain aging)phenomenon in SUS316 steel was investigated using isothermal and non-isothermal tensile tests of simulated HAZ(heat-affected zone)thermal cycles.Isothermal tensile tests were performed on SUS316 in the peak temperature range of 20-700°C,with strain rates varying from 4.2×10^(-3)to 4.2×10^(-5)s^(-1).Based on the appearance of discontinuous plastic flows,expressed as serrations,and the hardening phenomenon of the tensile samples,the conditions for the occurrence of DSA in the SUS316 steel were investigated.Furthermore,the extent of hardening due to DSA was evaluated by comparing the hardness values of the SUS316 and SUS316EHP steels after the tensile tests.To confirm the effect of DSA on hardness in the HAZ of the welded SUS316 steel,non-isothermal tensile tests of the simulated HAZ thermal cycles were performed using a Thermec Master.The relationship between the increase in Vickers hardness due to DSA and the strain in the HAZ was determined;the effect of DSA on hardness in the HAZ could be predicted.The DSA in SUS316 steel was found to be mainly attributed to the dynamic interaction of dislocations with C and N interstitial atoms during high-temperature deformation.

关 键 词：Dynamic strain aging HARDNESS SERRATION heat-affected zone SUS316 

分 类 号：TG1[金属学及工艺—金属学]