通过粉末床铺设置尼龙微粉, 进行选择性激光烧结(SLS), 制备了尼龙6(PA6)拉伸试样。分析了所制备样品在三维方向上的拉伸性能, 研究了拉伸断口的微观形态。结果表明, 所制备的样品致密无孔隙。激光扫描方向和面堆积方向的拉伸强度分别为42.7 MPa和42.5 MPa, 高于体堆积方向的拉伸强度39.3 MPa;激光扫描方向和面堆积方向的断裂伸长率约为体堆积方向的两倍。断口分析显示, 拉伸断口由裂纹萌生区和裂纹扩展区组成, 裂纹起源于未熔融PA颗粒与熔融粘结PA的界面。

Polyamides 6 (PA6) samples were produced for tensile test by selective laser sintering (SLS) with a powder-based process. The tensile properties of the samples were investigated in the three directions relative to SLS process and the microstructure of the tensile fracture was researched. Results show that the samples are compact and imporous. The tensile strength is 42.7 MPa and 42.5 MPa in the direction of laser scanning and overlapping. But the tensile strength is 39.3 MPa in the vertical direction. In addition, the elongation at break of the samples in the direction of laser scanning and overlapping is about twice as much as that in the vertical direction. The fraction microstructure indicated that the fraction is composed of crack initiation zone and fast propagation zone. The crack originated from the interface of un-melting PA6 particles and the melting PA6.