高强Q&P钢中残留奥氏体的TRIP行为  

TRIP effect of retained austenite in high strength Q&P steel

作　　者：田敬成[1] 孙艳波[1] 滕敦波[1] 乔玉新[1] Tian Jingcheng;Sun Yanbo;Teng Dunbo;Qiao Yuxin(College of Engineering,Yantai Nanshan University,Yantai Shandong 265713,China)

机构地区：[1]烟台南山学院工学院

出　　处：《金属热处理》2019年第7期169-172,共4页Heat Treatment of Metals

基　　金：山东省自然科学基金(ZR2018MEM007)

摘　　要：用EBSD和XRD表征了Q&P钢不同应变量下的残留奥氏体(RA)演变情况,分析探讨了其演变机制。结果表明:淬火温度为200℃时,Q&P钢具有良好的综合力学性能,抗拉强度达到1605 MPa,伸长率达到12%。RA主要呈粒状均匀分布在铁素体和马氏体的边界处,尺寸在0.2~0.5μm。随变形的进行,RA的含量呈现逐渐降低的趋势,且前期的降低幅度较大;经8%的应变后,62%的RA发生了TRIP效应,应力也基本达到稳态值。试样拉断后,断口附近的RA含量约2.8%,整个单向拉伸过程68%的RA发生了TRIP效应。The retained austenite evolution process of a Q&P steel under different deformation amounts was characterized by using X-ray diffraction(XRD)and electron back-scatter diffraction(EBSD),and the corresponding evolution mechanism was discussed.The results indicate that the optimal mechanical properties can be obtained by quenching at 200℃,where the tensile strength reaches 1605 MPa and the elongation reaches 16%.The retained austenite exists at the boundaries between ferrite and martensite laths,with sizes of 0.2-0.5μm.With the progress of deformation,the fraction of RA shows a trend of gradually decreasing,and has larger reduction in the early stage.After8%strain,the TRIP effect occurs in 62%of the RA,and the stress basically reaches the steady-state value.After the specimen broken,the RA content near the fracture is about 2.8%,and the TRIP effect occurs in 68%of the RA in the whole uniaxial tensile process.

关 键 词：高强Q&P钢 残留奥氏体 演变机制 马氏体 

分 类 号：TG156.31[金属学及工艺—热处理]