为了提高轴承的表面硬度、耐磨性，减小能源消耗，改善传统淬火环境，利用400 W基模光纤激光器对GCr15钢进行了淬火研究。分析了扫描速度和离焦量等工艺参数对淬火层的影响。光纤激光淬火相变硬化区的组织为细小马氏体和少量球状碳化物。淬火层的显微硬度随扫描速度的增加先增大后减小，随离焦量的增加也先增大后减小。当激光功率P=400 W、扫描速度v=0.6 mm/s、离焦量f=0时，淬火层的显微硬度达960 Hv，是基体的4.4倍。摩擦磨损实验结果表明，GCr15钢经光纤激光淬火后耐磨性显著提高，其磨损机制主要为氧化磨损、机械磨损和磨料磨损。

In order to increase the surface hardness and wear resistance of the GCr15 steel, as well as reduce the energy consumption and improve the traditional quenching environment, laser quenching is carried out on GCr15 steel with a 400 W fundamental-mode fiber laser. The effects of scanning speed and defocusing amount on the quenching layer are analyzed. The microstructure of the hardened region consists of fine martensite and a few spheroidal carbide. The microhardness increases with the increase of scanning speed and then decreases, and the same for the defocusing amount. The microhardness of GCr15 steel is 960 Hv after being quenched with fiber laser power of 400 W, scanning speed of 0.6 mm/s and defocusing amount of 0, which is 4.4 times of that of the matrix. The wear resistance of GCr15 steel quenched by fiber laser is significantly improved. The wear mechanism is mainly oxidation wear, mechanical wear and abrasive wear.