光固化快速成型中零件非水平下表面的支撑设计规则研究

激光固化快速成型制造中,支撑结构设计的优劣极大影响原型的制作精度。首先通过分析非水平下表面的分层制作过程,研究了其翘曲变形的机理。利用可仿真成型过程中层间力学行为的有限元计算模型,对层间悬臂量与翘曲变形量的关系进行了有限元计算仿真与试验验证。针对激光成型过程中零件需要支撑的非水平下表面,从激光固化快速成型制造中支撑结构的作用出发,以成型精度为设计目标,通过有限元计算仿真、试验验证等手段研究提出了针对零件中非水平下表面的支撑结构形式、布局及支撑间距等支撑设计规则。通过试验验证,按该规则对零件的非水平下表面进行支撑结构设计,可有效地保证激光固化快速成型的制作质量。

SUPPORT DESIGN RULES FOR PART'S NON-HORIZONTAL UNDERSURFACE IN STEREOLITHOGRAPHY

In stereolithography, support structural design will greatly affect the building accuracy of the prototype. The warping mechanism is studied through the analysis on the building process of part's non-horizontal undersurtace. Then with FEM calculation model of the mechanics behaviors between adjacent layers during the prototype building process, the FEM calculation simulation and experimental verification on the relationship between overhang length and warpage are performed, hence some design rules about the structure, layout and intervals of the support are suggested aiming at improving the building accuracy of the prototype. Through experiment, it is proved that these design rules can effectively ensure the building quality of the SL prototypes.