钛粉选区激光烧结三维瞬态温度场模拟

Simulation of three Transient Temperature Field in Selective Laser Sintering

考虑材料在烧结过程存在着相变潜热的特性和材料热物性参数随温度变化特性等,基于ANSYS建立选区激光烧结(Selective Laser Sintering,SLS)成型过程的模型,并且利用ANSYS参数化设计语言(APDL)实现了激光高斯热源的移动加载。以纯钛粉末为烧结材料进行三维瞬态温度场模拟。模拟结果表明:由于热积累效应,随着扫描时间的增加,熔池的温度越来越高,热影响区也随之增大;光斑中心热影响区随激光功率增加而扩大,同时热影响区温度也随激光功率增加在提高;扫描速度小,容易造成液相的流动,出现孔洞,扫描速度过大,则粉末不能完全熔化。

Considering the variation of latent heat of phrase change and thermal and physical properties of materials with temperature, A model of SLS is established based on ANSYS. And by using the ANSYS parameter design language, the moving of laser beam can be controlled. It is simulated for a three dimensional transient temperature field to sinter pure Ti material. The simulation results show that with the time increasing,the temperature of the molten pool becomes higher and haz becomes bigger because of the heat accumulative effect; with the increase of laser power ,Heat affected zone to expand, and heat affected zone temperature also increases;and that liquid phase flows easily and holes appear because of slow scanning speed, contrarily, the powder can not be melted completely.