利用激光成型技术制备了Fe基合金样品,研究了激光扫描速度对成型的Fe基合金组织与晶化行为的影响。结果表明,在一定激光功率下,随着扫描速度的增大,熔化区和热影响区内均发生了大面积的晶化,熔化区内的析出相的形貌和尺寸未发生明显的变化,而热影响区内的析出相的尺寸不断减小。采用Marc有限元软件模拟了激光快速成型过程,得到了各扫描速度下合金的熔化区和热影响区内的热循环曲线,分析了Fe基合金未能获得非晶相的原因。

Fe-based alloys are prepared by the laser rapid forming technique. The influence of scanning speed on the microstructure and crystallization behavior of the formed Fe-based alloys is studied. The results show that, under a certain laser power, the large area of crystallization occurs both in the fusion zone and the heat affected zone with the increase of the scanning speed. The morphology and size of the precipitated phase in the fusion zone do not change obviously, however, the size of the precipitated phase in the heat affected zone decreases gradually. The laser rapid forming process is simulated by the Marc finite-element software, the thermal cycling curves in the fusion zone and the heat affected zone under different scanning speeds are obtained, and the reason why non-crystallization phase occurs for Fe-based alloys is analyzed.