激光硬化在轴类零件上的应用研究 Study of Laser Hardening Used in Cylindrical Workpiece

半导体激光硬化是在工业应用中的高新技术，但当被硬化表面大于激光光斑时，便会发生回火现象。针对轴类零件的激光硬化，在对激光源进行闭环控制的条件下，高速旋转待加工零件，使激光光源能量在轴类零件圆周均匀分布，从而产生一个环形可见光斑，对圆周表面进行同步加热硬化，从而避免了回火现象的发生，在工件表面形成一个均匀的硬化层。 Laser hardening by means of diode laser is an innovative technique in industrial applications, but when the treated surface is larger than the laser spot, lap weld tempering, a well-known problem in laser hardening occurs. To avoid the lap weld tempering phenomenon, Visible Spot (VS) technique is investigated for cylindrical workpieces. In case of shaft parts, circular laser hardening is adopted by imposing a high rotational speed to the workpieces under the close loop control laser hardening system. A circular apparent spot is generated to heat the all the annular surface of the workpiece contemporaneously, as a consequence, lap weld tempering is avoided.