SPS制备氮化硅/锌铝基复合材料的组织和性能研究

通过放电等离子烧结工艺制备了氮化硅/锌铝基复合材料,重点探讨了氮化硅添加量对氮化硅/锌铝基复合材料致密度、硬度和摩擦性能的影响.采用扫描电子显微镜(SEM)及电子探针X射线显微分析仪(EPMA)对样品的微观组织进行了分析,并使用显微硬度仪、旋转摩擦试验仪对其性能进行了研究.结果表明:氮化硅在样品中分散均匀,且氮化硅的加入能够明显提高样品的致密度和硬度.当在锌铝合金中加入质量分数为20％氮化硅时,氮化硅/锌铝基复合材料致密度达到95.53％,同时与高锌铝合金烧结试样相比,其硬度提高了 58.5％,达到162.56HV.氮化硅/锌铝基复合材料的耐磨性随着氮化硅的添加呈现先增加后下降的趋势,添加量为20％时摩擦系数达到最佳为0.210 3,磨损量为0.003 37 mm3.

Microstructure and properties of Si3N4/Zn-Al matrix composites prepared by SPS

Si₃N₄/Zn-Al matrix composites were prepared by spark plasma sintering (SPS) process. The effects of Si₃N₄ addition on the density, hardness, and friction performance of Si₃N₄/Zn-Al matrix composites were discussed. The microstructure of the samples was analyzed by SEM and EPMA. The mechanical properties of the samples were studied by microhardness tester and rotary friction tester. Results show that Si₃N₄ was well dispersed in the sample, and the density and hardness of the sample were increased obviously after adding Si₃N₄. The density of Si₃N₄/Zn-Al matrix composite reached 95.53% when the Si₃N₄ content was 20%, and the hardness wasincreased by 58.5%, reached 162.56HV, compared with high zinc aluminum alloy samples. With the addition of Si₃N₄, the wear resistance of Si₃N₄/Zn-Al matrix composites increased first and then decreased. When the content of Si₃N_4was 20%, the friction coefficient reached the best value of 0.210 3, and the wear loss was 0.003 37 mm³.