摘要
通过微拉伸、电子背散射(EBSD)、透射电子显微镜(TEM)等手段,研究了具有亚稳奥氏体相的节约型双相不锈钢在1 000~1 200℃范围内不同固溶温度下的组织与性能的演变规律;探讨了固溶温度对形变诱导塑性(TRIP/TWIP)的作用机制。结果表明,随着固溶温度的升高,抗拉强度与伸长率均先升高后降低,而亚稳奥氏体相比例由74%(1 000℃)降低到37%(1 200℃);1 050℃固溶时,试验钢表现出最佳综合性能,抗拉强度达到960 MPa,伸长率达到62%,强塑积达到60 GPa·%。在经拉伸变形的微观结构中形变诱导马氏体与形变孪晶共存,表明试验钢中亚稳奥氏体相的变形机制主要受TRIP及TWIP共同控制,从而导致其塑性变形过程呈现多阶段应变硬化特征,而钢中铁素体相的变形机制主要变形为位错的滑移。
The evolution of microstructure and properties of a lean duplex stainless steel with metastable austenite phase at different solution temperatures of 1 000-1 200 ℃ were investigated by tension,transmission electron microscopy(TEM)and electron back-scattered diffraction(EBSD).The mechanism of solution temperature on the plasticity induced by deformation was discussed.The results show that with the increase of solution temperature,the tensile strength and elongation increased firstly and then decreased.The ratio of metastable austenite phase decreased from 74%(1 000 ℃)to 37%(1 200 ℃).When the solid solution was 1 050℃,the tested steel showed the best comprehensive performance with tensile strength of 960 MPa,elongation of 62% and the strength and ductility product of nearly60 GPa·%.Deformation induced martensite and deformation twins were found in the metastable austenite after tensile deformation,which indicated that the deformation mechanism of the metastable austenite in the present steel was mainly affected by both TRIP and TWIP,which led to the multi-stage strain hardening characteristics.On the other hand,the deformation mechanism of the ferrite phase was dominated by the slip of the dislocation.
出处
《钢铁》
CAS
CSCD
北大核心
2017年第4期55-60,99,共7页
Iron and Steel
基金
国家自然科学基金资助项目(51675467)
河北省自然科学基金资助项目(E2016203284)
河北省高等学校创新团队领军人才培育计划资助项目(LJRC012)
中国博士后科学基金资助项目(2016M600194)
关键词
节约型双相不锈钢
固溶温度
TWIP效应
TRIP效应
加工硬化
lean duplex stainless steel
solution temperature
twinning induced plasticity(TWIP)effect
transformation induced plasticity(TRIP)effect
work hardening