75CrMnMo铸钢轧辊激光熔凝强化的组织及性能分析

Study on Microstructures and Mechanical Properties of Laser Hardening Roller Steel 75CrMnMo

应用 5 k W连续 CO2 激光器对铸钢轧辊进行激光熔凝强化处理并进行显微组织分析和硬度测试。结果表明 ,其试样剖面组织区域分为激光熔凝强化区 (细小马氏体 +残余奥氏体 +碳化物 ) ,激光相变强化区 (马氏体 +残余奥氏体 +碳化物 ) ,过渡区和母材 4个区域。激光处理后可达 70～ 85 HSD。熔凝区和相变硬化区的淬硬深度依工艺参数不同 ,可达 1～ 2 mm。此工艺可以作为提高轧辊过钢量的一种途径。

Using a 5 kW continuous wave CO 2 Laser to per fo rm the laser melting treatment experiment on specimen of 75CrMnMo roller steel, the microstructure and the microhardness of the specimen were measured The resu lts show that its section is divided into melted zone consisted of fine martensi te, residual austenite and carbides, quenched zone composed of martensite, resid ual austenite and carbides, heat affected zone and base metal The region and th e mircohardness of various zones are related to the laser processing parameters. The hardening effect is obvious after laser hardening treatment(up to 70～85HS D) The hardening depted of melted zone and quenched zone may be up to 1～2 mm