选区激光熔化成型悬垂结构的计算机辅助工艺参数优化

为了提高选区激光熔化(SLM)成型悬垂结构的质量,从调节成型方向和能量输入入手研究悬垂结构的计算机辅助工艺参数优化。以减小零件模型整体难成型悬垂面的面积为目标,以零件模型非成型方向的两个旋转角度为优化变量,建立成型方向的优化模型,并基于遗传算法实现优化模型参数的求解。通过遍历零件模型中的所有三角面片,建立倾斜角静态查找表,并在成型时查表实现能量输入的实时调节。实验结果表明,经成型方向优化,零件模型难成型悬垂面的面积从555.12mm2减小为16.211mm2,所需支撑数量明显减少;成型后所得零件无明显悬垂物和翘曲变形,成型质量明显改善。

Computer-Aided Optimization of the Process Parameters for Fabricating Overhanging Structure by Selective Laser Melting

To improve the fabricating quality of overhanging structure in selective laser melting (SLM), the computer-aided optimization of process parameters is studied, which focuses on the fabrication orientation and the power input. The optimization model of the fabrication orientation, which is aiming at reducing the difficultly fabricating overhanging surface area, is proposed. The genetic solution for the model is studied. The static lookup table to adjust the energy input duly is built by traversing all the triangles in the stereo lithography (STL) file. The experimental results show that the difficultly fabricating overhanging surface area reduces from 555.12 mm2 to 16.211 mm2 after the optimization of the fabrication orientation, which leads to the less support needs, and the fabrication quality is obviously improved without so much overhang and deformation.