摘要
制备了一种含回火马氏体组织的TRIP钢(TAM钢),利用拉伸试验机、金相显微镜以及XRD对其力学性能、微观组织特别是残留奥氏体进行了研究,并与传统的TRIP钢进行对比。结果表明:TAM钢的抗拉强度略低于传统的TRIP钢(TPF钢),但是其伸长率远远高于TPF钢,高达32%以上,且拥有良好的加工硬化;TAM钢的微观组织由多边形铁素体、贝氏体、残留奥氏体以及回火马氏体构成;TAM钢的残留奥氏体量和碳含量与TPF钢没有明显差异,但是其残奥分布位置却不同,TAM钢中有部分残奥分布在回火马氏体组织内。在此基础上通过SEM原位拉伸试验对TAM钢在变形过程中的裂纹扩展进行了观察,发现裂纹前端在扩展过程受阻于到回火马氏体。
A kind of TRIP steel containing annealed martensite was developed in the laboratory, mechanical properties, microstructure and retained austenite characteristics of the steel were studied by means of tensile tests, optical microscope and XRD. The results show that compared with traditional TRIP steel(TPF steel), the tensile strength of the TRIP-aided annealed martensitic (TAM) steel is slightly lower than that of TPF steel, however, its elongation is much higher, reaching to more than 32% , and work hardening performance is excellent. The microstructure of the TAM steel consists of polygonal ferrite, bainite, retained austenite and annealed martensite. No significant difference in the amount of retained austenite and its carbon content between TAM steel and TPF steel is observed, but the distribution of retained austenite varies for the two steels, some of retained austenite scatters within the annealed martensite for the TAM steel. On this basis, the in situ tensile test is employed to observe the crack propagation during deformation of TAM steel and the result shows that annealed martensite can block the crack propagation effectively.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2013年第2期42-46,共5页
Transactions of Materials and Heat Treatment
基金
国家自然科学基金资助项目(50804005)
关键词
TAM钢
回火马氏体
力学性能
微观组织
扫描原位拉伸
TAM steel
annealed martensite
mechanical property
microstructure
in-situ SEM tensile test