选区熔化过程多尺度多物理场建模研究进展

选区熔化技术是一种基于粉末床的、能够精确成形复杂零件、调控微观组织和性能的金属增材制造技术,其成形过程的计算机模拟对于生产实践具有重要指导意义。综述了国内外的研究现状,首先介绍选区熔化技术的原理及其特点;然后介绍国内外对选区熔化过程已经开展的计算机模拟技术的研究进展;并进一步重点介绍针对电子束选区熔化过程的多尺度多物理场模型,主要包括:(1)微观尺度电子束与材料相互作用的能量吸收模型;(2)细观尺度从铺粉到粉末加热、熔化、流动、沉积成形全过程的模型;(3)宏观尺度零件成形过程模型。

Research Progress of Multi-Scale Multi-Physics Modeling for Selective Melting Process

Selective melting is a powder bed based metal additive manufacturing processes,and capable of manufacturing components with complex shapes and manipulating the material micro-structures and properties locally and globally.Computational modeling of the manufacturing processes provides valuable instructions to advance the technologies.This paper introduces the research progress in this regard.Firstly,the principle and characteristics of laser/electron beam selective melting are introduced.The state-of-the-art of numerical modeling of the manufacturing processes is summarized.The multi-scale multi-physics models for electron beam selective melting will be presented in detail,which consist of (1) a micro-scale electron-material interaction model;(2) meso-scale models of powder particles from being spread to being heated,melted and solidified;(3) a macro-scale model of part fabrication process.