PS/GF复合粉末选择性激光烧结弯曲强度的实验研究

Research on Bending Strength of PS/GF Composite Powders Based on Selective Laser Sintering

针对选择性激光烧结工艺中聚苯乙烯(PS)粉烧结件强度较低的问题,采用改性的短玻璃纤维粉(GF)对PS粉进行增强。研究了GF质量分数和工艺参数对PS/GF复合粉末烧结件弯曲强度的变化规律,采用正交试验和方差分析法进行工艺参数优化分析。结果表明,PS/GF复合粉末最佳配比为9∶1,平均粒径为82. 66μm,在工艺参数范围内随着分层厚度、扫描速度和扫描间距的增大,弯曲强度降低。在预热温度75℃和激光功率25 W条件下,最佳工艺参数组合为分层厚度0. 18 mm,扫描速度1 200 mm/s,扫描间距0. 28 mm。此时,PS/GF复合粉末烧结件的弯曲强度为12. 75 MPa,比纯PS粉烧结件的弯曲强度提高25. 12%。

In view of low strength problem of polystyrene （PS） powder sintered parts in the process of selective laser sintering, PS powder was reinforced by modified short glass fiber powder. The changing regularity of the GF content and process parameters on the bending strength of PS/GF composite powder sintered parts were studied. The process parameters were optimized by using orthogonal experiment and variance analysis. The results show that the optimum ratio of PS/GF composite powder is 9 ： 1 and the average particle size is 82. 66 μm. During the range of process parameters, bending strength is decreased with the increase of layer thickness, scanning speed, scanning interval. Under the condition of preheating temperature 75℃ and laser powder 25 W, the optimal combinations of process parameters are layer thickness 0. 18 mm, scanning speed 1 200 mm/s and scanning interval 0. 28 mm. At this point, the bending strength of the PS/GF sintered part can reach 12.75 MPa, which is increased by 25.12% compared with pure PS sintered part.