以聚苯乙烯粉末为原料，采用选择性激光烧结技术成型H型梁，探讨了激光功率、扫描速度、单层厚度、扫描间距耦合作用对收缩率的影响。结果表明：工艺参数耦合作用对收缩率具有较大影响，通过多工艺参数协同控制，可以减小H梁收缩率，这对SLS聚苯乙烯结构的精确成型具有重要意义。

Polystyrene(PS)powder was sintered to H beam by using selective laser sintering(SLS). The coupling effects of laser power， scanning velocity， layer height and scanning thickness on the shrinkage ratio were studied. The results showed that the coupling effects of process parameters have important impact on the shrinkage ratio. The shrinkage ratio may be reduced by collaborative controlling of process parameters，which has significant meaning for precision forming of PS structure by selective laser sintering.