20CrMnTi齿轮钢激光淬火的研究

摘要

This paper studied the laser quenching method as an alternative to traditional carburizing method in 20CrMnTi gear steel strengthening.The influence of different laser parameters on the properties of 20CrMnTi gear steel was studied by electron microscope, microhardness tester, pin wear tester and electrochemical workstation.The results show that dense fine martensite structure is formed on the surface of the 20CrMnTi sample after laser quenching processing.The microhardness is greatly improved compared to the original material.The property of sample is optimized when the spot diameter is 1 mm.The scanning speed is 16 mm/s, the pulse width is 2.5 ms.The frequency is 10 Hz, and the current is 180 A with the quenching thickness about 240 μm.The highest surface hardness reaches 739 HV, exceeding 545 HV to the original sample and 85 HV to the carburizing quenching sample.Despite the relative thinner quenching layer with comparison to traditional carburizing and quenching method, the mechanical properties can wear resistance and corrosion resistance, as is greatly improved.%评估了齿轮通过激光淬火代替传统渗碳淬火的可行性.通过用电子显微镜、显微硬度计、销盘磨损仪、电化学工作站,确定了不同激光参数对于20CrMnTi齿轮钢激光淬火试样性能的影响关系.结果表明:20CrMnTi齿轮钢经过激光淬火后,在试样表面形成了致密的细小的马氏体组织,表面及亚表面显微硬度得到了极大的提高.当光斑直径为1 mm,扫描速度为16 mm/s,脉宽为2.5 ms、频率为10 Hz、电流为180 A,选取试样淬火后效果最好,淬火层深度可达240 μm,表面硬度达到了739 HV,超过原始试样545 HV,超过渗碳淬火试样85 HV.虽然淬火层低于渗碳淬火后渗碳淬火层深度,但获得的力学性能、耐磨性能、耐蚀性能均优胜于渗碳淬火.