Improving oxidation resistance of TZM alloy by deposited Si–MoSi2 composite coating with high silicon concentration

The oxidation behavior of Si–MoSi2 composite coating deposited on titanium-zirconium-molybdenum alloy (TZM) at 1200 °C in air was discussed. The oxidation tests show that the mass loss of coated samples is only 0.021 mg/cm2 after oxidation at 1200 °C for 9 h, whereas the bare TZM suffers serious volatilization and decomposition, and the mass loss is only 2.488 mg/cm2 after oxidation for 20 min. The coated samples presents good oxidation resistance compared to the bare TZM alloy at medium temperature, which is due to the formation of self-healing SiO2 protective layer and the dense structure of coating. Moreover, the high surface silicon concentration also plays a positive role in the rapid formation of SiO2 protective layer.