Field assisted sintering of SiC using extreme heating rates

Abstract

Several challenges still exist in the fabrication of silicon carbide (SiC) ceramic components associated with using multiple step processes and sintering at high temperature which result in long lead times. This challenge is being addressed by exploring an emerging sintering technology called field assisted sintering technology (FAST), also known as spark plasma sintering. The objective of this study is to sinter SiC to near theoretical density using the FAST technique and study the effect of using extreme heating rates during sintering. All samples were sintered under identical temperature and pressure of 2000 °C and 45 MPa. Resulting samples were characterized for density, microhardness, grain size, and microstructure evolution. The results showed that density decreased slightly and grain size increased as heating rate was varied from 50 to 400 °C/min.