调质工艺对Cr5钢组织和性能影响  

Influence of Tempering Temperature on Microstructure and Properties of Cr5 Steel

作　　者：元亚莎 王文焱[1] 岳宗格 岳慎伟 谢敬佩[1] 

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471023 [2]中信重工机械股份有限公司,河南洛阳471003

出　　处：《河南科技大学学报（自然科学版）》2014年第4期1-4,9,共5页Journal of Henan University of Science And Technology:Natural Science

基　　金：河南省重大科技攻关基金项目(6020091020132-1);洛阳市科技支撑基金项目(1301057A)

摘　　要：用扫描电子显微镜、X射线衍射仪、拉伸试验机和洛氏硬度计,观察和分析了Cr5钢调质处理前后的显微组织以及调质处理后的断口形貌、抗拉强度、延伸率和硬度。研究结果表明:调质处理前Cr5钢中碳化物类型有M7C3、M23C6和M3C2;调质处理后Cr5钢的显微组织得到明显改善,点状偏析基本消除,基体上弥散分布着细小的碳化物;断口形貌由小准解理刻面逐渐向韧窝转变;抗拉强度和硬度值随回火温度的升高而降低,延伸率有所提高;回火温度为540℃左右时,抗拉强度、延伸率和硬度值分别为1 429.9 MPa、2.90%和49.2HRC,有良好的力学性能。The microstructure( before and after quenching and tempering),and fracture morphology,tensile strength,ductility,hardness(after quenching and tempering)of Cr5 steel were observed and analyzed by means of scanning electron microscopy,X-ray diffraction,tensile test machine and Rockwell hardness tester respectively. The results show that the carbides of Cr5 steel are mainly M7C3,M23C6 and M3C2before quenching and tempering. After quenching and tempering,the microstructure of Cr5 is improved dramatically.The spot segregation is eliminated basically,and the thin carbides are distributed in the matrix. The morphology of the fracture is changed from small quasi cleavage facet to cavity. With the increase of tempering temperature,the tensile strength and the hardness are decreased,and the ductility is increased. The materials have good comprehensive mechanical performance at about 540 ℃ of the tempering temperature. The tensile strength is 1 429. 9 MPa,the ductility is 2. 90% and the hardness is 49. 2HRC.

关 键 词：CR5 钢 调质处理 微观组织 力学性能 

分 类 号：TG156.1[金属学及工艺—热处理]