Investigation of MoSi2 melt infiltrated RSiC and its oxidation behavior

Melt infiltration process was employed to fill molten MoSi2 into the pores of recrystallized silicon carbide (RSiC) to improve the oxidation resistance of RSiC, and an almost fully dense RSiC–MoSi2 composite with the microstructure of two-phase interpenetrated network was obtained. The phase compositions of the composites are mainly SiC and MoSi2, including a small amount of Mo4.8Si3C0.6 and Mo5Si3. The flexural strength of the composites at room temperature was 11–32% higher than that of as-received RSiC. The cyclic oxidation tests at 1500 °C indicated that both the RSiC–MoSi2 composites and RSiC exhibited a parabolic oxidation behavior, and the corresponding parabolic rate constants of the composites were almost an order of magnitude lower than those of RSiC, resulting in a great improvement of oxidation resistance of RSiC–MoSi2.