Molybdenum disilicide (MoSi_2) has been applied as protective coating material on various substrates fabricated by different methods due to its good oxidation resistance at elevated temperature, relatively low density and coefficient of thermal expansion and high thermal conductivity. In this work, MoSi_2 coatings were fabricated by low pressure plasma spraying technology (LPPS). Their morphology, composition and microstructure characteristics were intensively investigated by SEM, XRD, EDS and TEM. The oxidation behaviors of MoSi_2 coatings were also explored. The results showed that the MoSi_2 coating was compact with porosity less than 5%. Its microstructure exhibited typical lamellar character. The MoSi_2 coating was made up of grains with irregular shapes and different sizes of 0.1-0.2 μm. It was mainly composed of tetragonal and hexagonal MoSi_2 phases. A small amount of tetragonal Mo_5Si_3 phase formed and randomly distributed in the matrix of MoSi_2. The MoSi_2 coating exhibited excellent oxidation-resistant behavior at 1773K, which resulted from the continuous dense glassy SiO_2 film formed on its surface.
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