The polymer laser sintering (PLS) process is one of the most promising additive manufacturing (AM) technologies for polymeric materials. However, the technique has challenges because the physical, mechanical, and chemical properties of the polymeric powder deteriorate due to the high temperatures prevailing in the build chamber during manufacture. These high temperatures cause agglomeration of powder, which leads to a decrease in the flowability of powder. There is also a related drop in the coalescence of the powder granules during PLS, which results in porosity that undermines the mechanical integrity of printed parts. Moreover, the viscosity of the melt increases due to cross-linking of molecular chains. This, in turn, increases the tensile strength of the printed components at the expense of the percentage elongation at break. Thus, high prolonged processing temperatures decrease the reusability of polymeric materials used in PLS. In this paper, a review of the studies conducted to investigate ways of reducing the effects of high temperature on polymeric powders is presented.

中文翻译：

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用于减少与聚酰胺 12 和聚丙烯激光烧结相关的高温影响的方法综述

聚合物激光烧结 (PLS) 工艺是最有前途的聚合物材料增材制造 (AM) 技术之一。然而，该技术面临挑战，因为聚合物粉末的物理、机械和化学性质会由于制造过程中构建室中普遍存在的高温而恶化。这些高温导致粉末结块，从而导致粉末流动性降低。在 PLS 期间，粉末颗粒的聚结也有相关的下降，这会导致孔隙率降低，从而破坏打印部件的机械完整性。此外，由于分子链的交联，熔体的粘度增加。反过来，这会增加打印部件的拉伸强度，但会降低断裂伸长率。因此，长时间的高加工温度会降低 PLS 中使用的聚合物材料的可重复使用性。在本文中，回顾了为研究减少高温对聚合物粉末的影响而进行的研究。