W.F. Zhang
,
Y.M. Chen and J.H. Zhu(State Key Laboratory for Mechanical Behavior of Materials
,
Xi'an Jiaotong University
,
Xi'an 710049
,
China)
金属学报(英文版)
A new non-uniform yield phenomenon is found during tension of austenite stainless steel at -190℃, which consists of elasto-plastic instability ξph and stress plateau ξL resulting from strain-induced martensite transformation. It is essentially different from non-uniform yield that is related to dislocation obstacles. The experimental results show that ξph and ξL increase with increaslng strain rate, and ξph, increases but ξL decreases with increasing prestmin.Tronsformation enengy of strain-induced martensite keeps a constant, 3.85×106J/m3, with increasing strain at the stages of both elasto-plastic instability and stress plateau.
关键词:
non-uniform yield
,
null
,
null
,
null
程晓娟
,
王弘
,
康国政
,
董亚伟
,
刘宇杰
金属学报
doi:10.3321/j.issn:0412-1961.2009.07.009
利用OM,SEM和XRD对单轴非对称应力循环下304不锈钢棘轮变形过程中的微观组织变化进行了实验观察.结果表明:304不锈钢棘轮变形过程中,当棘轮应变达到一定值后会产生应变诱发马氏体相变,形成板条状马氏体,并且随循环周次的增加,形成的应变诱发马氏体相对量逐渐增加.因马氏体相变而诱发的塑性变形对总的棘轮变形量产生一定的影响,材料的棘轮应变应由两部分组成,即应力引起的塑性应变和相变诱发的塑性应变.
关键词:
304不锈钢
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棘轮变形
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应变诱发马氏体相变
,
单轴应力循环
,
相变诱发塑性
