贝氏体等温温度对0.2C-1.5Si-2Mn-0.43Cu-0.26NiTRIP钢组织和性能的影响  

Effect of bainite isothermal temperature on microstructure and properties of 0.2C-1.5Si-2Mn-0.43Cu-0.26Ni TRIP steel

作　　者：周开春[1] 赵爱民[1] 尹鸿祥[1] 赵征志[1] 丁然[1] 丁箫楠[1] 

机构地区：[1]北京科技大学冶金工程研究院,北京100083

出　　处：《材料热处理学报》2015年第10期128-133,共6页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(51271035);教育部高等学校博士学科点专项科研基金(20110006110007)

摘　　要：应用CCT-AY-Ⅱ型钢板连续退火机、X射线衍射、扫描和透射电镜、EBSD和拉伸试验等研究了TRIP钢（0.2C-1.5Si-2Mn-0.43Cu-0.26Ni）贝氏体区（350~470℃）等温处理对组织和性能的影响。结果表明：在贝氏体等温温度为410℃时,TRIP钢综合力学性能最佳,抗拉强度达到1088 MPa,伸长率16.88%,强塑积18365 MPa·%。残留奥氏体在TRIP钢中存在的形态有粗大块状、薄膜状和细小粒状。其中薄膜状的残留奥氏体属于亚稳奥氏体,形变过程中发生渐进式转变,极大地发挥TRIP效应。残留奥氏体中的碳含量和薄膜厚度是决定残留奥氏体稳定性的关键因素。Microstructure and mechanical properties of the TRIP steel（ 0. 2C-1. 5Si-2Mn-0. 43Cu-0. 26Ni） austempered at isothermal bainite temperature（ IBT,350-470 ℃） were researched by means of CCT-AY-Ⅱ type continuous annealing simulation machine,X-ray diffraction,scanning electron microscopy,transmission electron microscopy,electron backscatter diffraction,and tensile test. The results show that when austempering at 410 ℃,the excellent mechanical properties including a good tensile strength（ 1088 MPa）,high elongation（ 16. 88%） and strength-ductility product（ 18365 MPa·%） can be obtained,. It is found that the retained austenite can be in the form of relative large blocks,thin films and small particles. The film-like metastable austenite is easier to transform during the deformation,so it will play a major role in exerting TRIP effect. The stability of the residual austenite is mainly determined by the carbon content and the film thickness of residual austenite.

关 键 词：TRIP钢 亚稳奥氏体 贝氏体等温温度 显微组织 力学性能 

分 类 号：TG142.1[一般工业技术—材料科学与工程]