Effect of additives on resistivity of reaction-bonded silicon carbide

The effect of additives Ni, Mo and Al is studied for the electrical resistivity of reaction-bonded silicon carbide (RB-SiC). Electrical resistivity measurements measured at room and high temperature show that they decrease by adding Ni, Mo and Al. With increased contents of additives, the electrical resistivity of RB-SiC will decrease. The effect of Ni and Mo on the resistivity is greater than that of Al. The additives Ni and Mo reacted with liquid Si such that Ni₂Si₃ and Mo₃Si₅ are formed at the grain boundaries of SiC, while Al is in the SiC solution with free Si.