Oxidation behavior of Al2O3 reinforced MoSi2 composite coatings fabricated by vacuum plasma spraying

MoSi2, MoSi2–10 vol.% Al2O3, MoSi2–30 vol.% Al2O3 (denoted as MA0, MA1, MA3, respectively) coatings were fabricated by vacuum plasma spraying (VPS), and their oxidation behavior was examined at low temperature (500 °C) and high temperature (1500 °C). The test at 500 °C showed that the addition of Al2O3 effectively restrained the pest oxidation of MoSi2. The MA1 coating had satisfactory fluid surface and presented good oxidation resistance at 1500 °C. However, the MA3 coating showed worse oxidation resistant behavior compared with the MA0 coating because of mullite formation.