GCr15钢表面激光淬火的组织与性能

利用HL-1500无氦横流CO2激光加工机对GCr15钢表面进行激光淬火处理。采用SSX-550型扫描电子显微镜(SEM)、XJL-02A立式金相显微镜(OM)、DMH-2LS努氏显微硬度计、ML-10滑动摩擦磨损试验机和ZF-3恒电位仪等设备对不同功率下相变硬化层的显微组织及性能进行研究。结果表明:相变硬化区的组织为细小针状马氏体和少量球状碳化物,过渡区的组织为马氏体、残留奥氏体、铁素体和碳化物;试样的硬化层硬度比基体提高了2.2～3.5倍,当激光功率为1050W时,硬化层深度最大,可达0.7mm,耐磨性比基体提高3倍,耐蚀性也显著提高。

Microstructure and properties of GCrl5 steel treated by laser quenching

Laser quenching was carried on GCr15 steel with HL-1500 no-helium crossflow CO2laser processing machine.Microstructure and properties of the hardened layers for different powers were studied by means of SEM,optical microscope,microhardness and wear tests and polarization curve measurement.Results indicate that the laser quenched layer is composed of hardened region,transition region and matrix.The microstructure of the hardened region consists of fine acicular martensite and retained austenites,and in the transition region tempered martensite,retained austenite,ferrites and carbides are observed.Hardness of the laser quenched GCr15 steel is in creased by 2.2～3.5 times than that of the un-treated steel.The depth of hardend layer reaches 0.7 mm,its wear resistance increases by 3 times than that of the matrix,and corrosion resistance of the hardened layer is also significantly inproved for CCr15 steel laser-quenched with laser power of 1050 W.