生产工艺对690 MPa级工程机械用钢组织与力学性能的影响  

Effects of Process on Microstructure and Mechanical Properties of 690MPa Grade Construction Machinery Steels

作　　者：惠亚军[1] 赵爱民[1] 赵征志[1] 黄耀[1] 李文远[1] 

机构地区：[1]北京科技大学冶金工程研究院,北京100083

出　　处：《机械工程材料》2013年第8期55-58,共4页Materials For Mechanical Engineering

摘　　要：利用控轧控冷工艺(TMCP)及与弛豫-析出-控制相变(RPC)技术相结合工艺制备了690MPa级高强度工程机械用钢,采用光学显微镜、扫描电镜和透射电镜等研究了不同生产工艺对钢组织和力学性能的影响。结果表明:TMCP工艺和TMCP+RPC工艺获得的试验钢组织都以板条贝氏体为主,同时含有少量粒状贝氏体和针状铁素体;与单纯的控轧控冷工艺相比,终轧后经弛豫处理的试验钢组织更加细小,因此其综合力学性能更优,屈服强度和抗拉强度分别达到715MPa与860MPa,伸长率达到20.6%。The 690 MPa grade structural steels for construction machinery were prepared using thermo mechanical control process （TMCP） and the process combined TMCP with relaxation-precipitation-controlling phase transformation technology （RPC）. The effects of different processes on the microstructure and mechanical properties of the steels were investigated by optical microscopy （OM）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM）. The results show that the microstructure of the steels prepared by TMCP and TMCPq-RPC process was mainly composed of lath bainite and a small amount of granular bainite and acicular ferrite. Compared to the TMCP, the steel prepared by TMCP--RPC technology had finer microstructure, and so it had the better comprehensive mechanical properties with a yield strength of 715 MPa and a tensile strength of 860 MPa and a elongation of 20. 6 %.

关 键 词：弛豫-析出-控制相变技术 超低碳贝氏体 工程机械 微观组织 

分 类 号：TG142.1[一般工业技术—材料科学与工程]