基于硅铝溶胶复合的碳化硅磨料制备与表征

Preparation and Characterization of Silicon Carbide Abrasives Based on Silica-Alumina Sol-Gel Composite

摘要: 碳化硅因其高硬度和良好的耐磨性而成为一种重要磨料。在碳化硅制备过程中往往会产生一些超细的碳化硅粉体，无法达到磨料使用要求。本文以所制备的硅铝溶胶作为粘结剂与碳化硅微粉进行混合、制粒、烧结，以获得可用作磨料的碳化硅粉体。通过激光粒度、XRD、SEM对样品进行表征发现：硅铝溶胶作为结合剂能有效结合碳化硅微粉，增大碳化硅颗粒粒径。硅铝溶胶浓度和烧结温度对样品粒径均有一定影响，溶胶浓度和烧结温度升高可以增大样品的粒径，但浓度过高对于粒径增加有限反而影响制粒，在溶胶浓度为10 wt%、烧结温度1300℃达到最优效果。

Abstract: Silicon carbide is a very important abrasive due to its high hardness and good wear resistance. The preparation of silicon carbide often produces some ultrafine silicon carbide powders that do not meet the requirements of abrasives. In this paper, Al₂O₃ and SiO₂ were used as binders to prepare silica-aluminum sols, which were mixed, granulated and sintered with silicon carbide micronized powder to obtain silicon carbide powder that can be used as abrasives. The samples were characterized by laser particle size, XRD, and SEM. It was found that the silica-aluminum sol as a binder could effectively bind the silicon carbide micro powder and increase the particle size of silicon carbide. Both the concentration of the silica-aluminum solute and the sintering temperature had an effect on the particle size of the samples. Increasing the concentration of the solute and the sintering temperature increased the particle size of the samples, but too high a concentration had a limited effect on increasing the particle size. The optimum result is achieved at a sol concentration of 10% and a sintering temperature of 1300˚C.