Effect of additives on selective laser sintering of silicon carbide

Silicon carbide-based composite ceramic is manufactured by one-stage selective laser sintering. The effect of the sintering parameters and raw materials on the sinterability of SiC based composite is studied. The optimization of the parameters is carried out. In a single stage of selective laser sintering, it is possible to achieve 87% relative density. The influence of particle size of feedstock, as well as BN and Y₂O₃ additives on the sinterability, mechanical and thermal properties of the samples are studied.

For composites that contain 10% BN, the thermal expansion coefficient increases from room temperature to 900 °C. The electrical resistivity decreases both in the room and at cryogenic temperature (−200 °C). The thermal conductivity and mechanical properties of BN-containing samples decrease as well. Yttrium oxide-containing samples show higher thermal conductivity and electrical resistivity than boron nitride-containing samples.