40Cr钢是一种主轴常用调质钢, 具有较高的强度、韧性和塑性。调制后的主轴其硬度与耐磨性能不太理想, 高速下容易在轴颈处磨损, 影响主轴工作精度。采用不同的激光相变硬化工艺对正火态40Cr进行表面处理, 找出适合高速主轴激光相变硬化方法, 提高材料的硬度、耐磨性和抗疲劳性。经过不同工艺处理后的试样分析, 得出了以激光功率1600 W, 光斑直径7 mm, 扫描速度15 mm/s的工艺硬度、层深等相对其他试样来说最为理想, 并着重对该工艺下各层金相组织进行了研究, 测量了层深与硬度。结果表明该工艺下试件表面硬度较低, 适合高速主轴的加工与磨削, 次表层硬度最高为40Cr主轴常规调质试件硬度的2.04倍, 且耐磨性较好。

40Cr steel is a common quenched axis steel with high, tough, and plastic cooperation. However, quenched steel for high speed spindle rigidity and resistance is not satisfactory. It is easy wear at axle journals and affacts the precision. 40Cr steel with normalized one has been hardened by laser. To find a good technics for high-speed spindle by laser surface hardening, to improve 40Cr steels hardness and wear resistance.Analyse kinds of samples which are harden by different technics. Diameter of facula 7 mm, laser power 1600 W, speed of scan 15 mm/s is the best parameters. Then microstructures analysis, rigidity measurement are carried out. The result: the sample with the technics is the best for high-speed spind machining and milling. The hardness of hypo-surface layers hardness is 2.04 times of the conventional heat treatment, and it is wearable.