激光功率对选择性激光烧结尼龙12密度和绝缘性能的影响

Effect of laser power on the density and insulation properties of SLS nylon 12

选择性激光烧结技术(SLS)发展迅速,技术成熟度高,可以打印任意复杂形状的结构,而传统注塑工艺很难制备某些具有复杂结构的绝缘件,因此SLS技术在制作复杂的绝缘结构方面具有显著优势。然而不同的烧结工艺参数对烧结件的性能具有较大影响。研究了不同激光功率下尼龙12烧结件密度和绝缘性能的变化规律及成因。选取不同的激光功率进行测试,以烧结件的密度、击穿场强、电导率和相对介电常数为指标,综合选取最优的激光功率。分析了尼龙12在烧结过程中的热氧化降解机理,烧结件的热氧化降解是导致烧结件性能劣化的主要原因。结果表明:在激光功率变化范围内,烧结件的密度和绝缘性能呈先提升后稳定再劣化的规律;最优的激光功率为9 W,对应的扫描速度为3000 mm/s,扫描间距为0.1 mm,此时尼龙12烧结件的密度为1.0106 g/cm^(3),直流击穿场强为81.57 kV/mm,电导率为4×10^(-13)S/cm。

Selective laser sintering(SLS)technology is developing rapidly and has been highly technology maturation,which can build complex insulation structures.However,it is difficult for traditional injection molding process to make some insulating parts with complex structures.Therefore,SLS technology has significant advantages in the production of complex insulating structures.However,different process parameters have great influence on the properties of samples.The density and insulation properties of nylon 12 samples under different laser powers were studied.Different laser powers were selected and the density,breakdown strength,conductivity and permittivity were taken as experimental indexes to select the optimal laser power.The mechanism of thermal oxidation degradation of nylon 12 was analyzed which resulted in the properties deterioration of samples.The results show that the density and insulation properties of samples are improved,then stabilized and degraded in the range of laser power.The optimal laser power is 9 W,the scanning speed is 3000 mm/s and the scanning spacing is 0.1 mm.The density of samples is 1.0106 g/cm^(3),the DC breakdown strength is 81.57 kV/mm and the conductivity is 4×10^(-13)S/cm.