激光选区烧结金刚石/碳化硅复合材料性能研究

Properties of Diamond/SiC Composites Prepared by Selective Laser Sintering

采用激光选区烧结(SLS)技术结合液相渗硅工艺制备了金刚石/碳化硅复合材料,研究了粉末原料中金刚石含量对SLS成形素坯和金刚石/碳化硅复合材料性能的影响,利用电子探针显微分析仪分析了复合材料的物相分布和硅-碳反应机理。结果表明,金刚石含量的增加可以有效提高复合材料的物理性能、机械性能和热学性能。金刚石/碳化硅复合材料的最大体积密度、抗弯强度和表面洛氏硬度HRA分别为(2.90±0.01)g·cm^(-3)、(231.15±3.27)MPa、78.06±0.54,在常温下的最低热膨胀系数和最高热导率分别为2.06×10^(-6) K^(-1)和207.21 W·m^(-1)·K^(-1)。

We prepared a diamond/SiC composites by selective laser sintering(SLS)technology combined with liquid silicon infiltration process,and investigated the effects of diamond content in powder raw materials on the properties of SLS green body and diamond/SiC composites.Moreover,we analyzed the phase distribution of the composites and the Si-C reaction between melt silicon and diamond by electron probe micro-analyser(EPMA).The results show that the increase of diamond content has an important function in improving the physical,mechanical,and thermal properties of the composite.The maximum bulk density,flexural strength,and surface Rockwell hardness HRA of the composite are(2.90±0.01)g·cm^(-3),(231.15±3.27)MPa,and 78.06±0.54,respectively.The lowest thermal expansion coefficient and the highest thermal conductivity at room temperature are 2.06×10^(-6) K^(-1) and 207.21 W·m^(-1)·K^(-1),respectively.