Abstract: Support structures were required in SLM processes to support overhanging features in order to hold the work piece in the place and remove heat away from the processes. If heat accumulation in overhangs was too large, it would cause defects such as warpage, collapse, residual thermal stress，et al. Therefore, the influences of support structures on the temperature field of SLM were studied, and  support structures with good comprehensive heat conduction were designed. Firstly, a three-dimensional finite element model of SLM was established. Then, the influences of the traditional support structures on the temperature field were studied. Finally,  support structures were designed and optimized based on the numerical simulation results. It was verified by finite element analyses and manufacturing experiments. Results show that compared with the traditional support structures, the top sintering layers of the thin plates supported by the new support structures have the lowest average node temperature and small temperature difference, showing good comprehensive heat conduction, and the degree of warpages of the thin plates is significantly reduced.

Key words: selective laser melting(SLM), temperature field, support structure, heat conduction

摘要： 添加支撑结构在选区激光熔化中必不可少，零件的悬垂特征需要添加支撑结构，起到固定零件和散热的作用，若悬垂特征热量积聚过大，会导致翘曲变形、塌陷、残余热应力等缺陷。研究了支撑结构对选区激光熔化温度场的影响，并设计优化了一种具有良好综合导热性的支撑结构。首先建立选区激光熔化三维有限元模型；然后研究传统支撑结构对温度场的影响；最后基于数值模拟结果对支撑结构进行设计优化，并通过有限元分析和制造实验进行验证。实验结果表明，与传统的支撑结构相比，由新支撑结构支撑的薄板顶部烧结层平均节点温度最低、温差较小，可表现出良好的综合导热性，且薄板翘曲变形程度显著降低。

关键词: 选区激光熔化, 温度场, 支撑结构, 导热性