一、前言激光是六十年代发展起来的新技术。六十年代中期,激光技术由实验室进入工业应用,出现了激光打孔、切割、划线等加工项目。后来又用于焊接。但它们只涉及对材料的加工,不引起材料本身的物理化学变化。七十年代初,伴随工业用大功率激光器的出现,诞生了激光热处理。激光热处理,是以大功率激光器做热源,用功率密度足够的激光束对金属表面进行扫 I. Introduction Laser is a new technology developed in the 1960s. The mid-1960s, laser technology from the laboratory into industrial applications, there have been laser drilling, cutting, marking and other processing projects. Later it was used for welding. However, they only deal with the processing of materials without causing the physical and chemical changes of the materials themselves. The early seventies, with the emergence of industrial high-power lasers, the birth of the laser heat treatment. Laser heat treatment, is a high-power laser as a heat source, with a laser beam of sufficient power density to sweep the metal surface