MoSi2 coating on Mo substrate for short-term oxidation protection in air

Because of their excellent oxidation resistance and high specific strengths, bulk MoSi2 and MoSi2-based composites are used for several high temperature applications. In this work, the effectiveness of a MoSi2 coating formed by pack siliconizing method has been evaluated in providing short-term oxidation protection to pure Mo substrate at 1100 and 1500 °C. In terms of weight change, coated Mo showed about ∼300 times better oxidation resistance than the bare metal at 1100 °C. The MoSi2 coating provided good oxidation protection to Mo up to 1 h at 1500 °C. The evolution of the surface morphology and the microstructure of the above coating during oxidation has been studied.