激光重熔技术在选区激光熔化中的研究进展

Research Progress on Laser Remelting in Selective Laser Remelting

摘要:

激光重熔使得材料表面的固化层再次快速熔化、凝固,从而提高了材料的致密度和表面质量。作为一种表面改性技术,激光重熔已经在传统制造工艺中得到了广泛的应用。近期研究表明,激光重熔技术也可以应用到选区激光熔化(SLM)中,实现消除缺陷并优化组织结构。激光重熔技术还可以提高零件的硬度和延展性等力学性能。本文主要总结了激光重熔对于常见SLM成形金属材料的质量提升作用,以及激光重熔工艺手段以及重熔参数(包括重熔激光功率、重熔扫描速度、重熔扫描间距和重熔次数)对于缺陷消除、组织结构优化的作用规律。

Abstract:

Laser remelting enables the solidified layers to melt and solidify rapidly again, thus could improve the relative density and surface quality. It is a type of surface modification technologies, and has been widely used in traditional manufacturing processes. Recent researches showed that laser remelting could be used to refine the microstructure, reduce the porosity and improve surface quality of SLM processed metals and alloys. Laser remelting technology can also improve the mechanical properties such as hardness and ductility. This paper made a thorough literature survey and summarized how laser remelting could affect the porosities, microstructures, surface qualities and residual stress of SLM processed metals and alloys. Furthermore, the working parameters of laser remelting and their influences on the porosities, microstructures, surface qualities and residual stress are introduced.