聚氨酯弹性体的选择性激光烧结

Selective Laser Sintering of Polyurethane Elastomers

研究了聚氨酯弹性体(TPU)粉末的选择性激光烧结(SLS)行为。研究了TPU烧结过程中粉床温度及激光能量密度对首层烧结区域翘曲行为的影响,确定TPU的烧结窗口为(Tc-Tg2);研究了粉体粒径及纳米二氧化硅含量对TPU烧结的影响,结果表明粒径在100μm左右的一个较宽范围内都可以正常打印,且打印制件能维持较好的精度和力学性能;随着纳米二氧化硅含量的增加,TPU粉体流动性逐渐变好,但烧结制件的力学性能呈现先升高后下降的趋势,当纳米二氧化硅质量分数为0.2%时,TPU烧结制件拉伸强度可达到28.8MPa,断裂伸长率为615%,此时TPU烧结性能最优异。

The selective laser sintering(SLS)behavior of polyurethane elastomer(TPU)powder was studied in this paper.The effect of powder bed temperature and laser energy density on the warpage behavior of the first layer sintering zone during the sintering process of TPU was studied,and the sintering window of TPU was determined to be(Tc-Tg2);the effect of powder particle size and nano-silica content on the properties of laser-sintered TPU was studied.The results show that when the particle size is in a wide range of about1 00μm,the printed parts can maintain good precision and mechanical properties;with the increase of nano-silica content,the flowability of TPU powder gradually becomes better,but the mechanical properties of TPU sintered parts increase first and then decrease.When the mas fraction of nano-silica is 0.2%,the tensile strength of TPU sintered parts can reach 28.85 MPa and the elongation at break is 615%,and the TPU has the best sintering performance.