Preparation and investigation of MoSi2/SiC coating with high infrared emissivity at high temperature

In this study, MoSi2/SiC coating with high infrared emissivity was fabricated by atmospheric plasma spray (APS) method, in view of the potential application in high temperature energy-saving area. The phase composition, microstructure, infrared emissivity and thermal shock resistance of the obtained coating were characterized. Compared with MoSi2 coating, the MoSi2/SiC coating exhibited a higher emissivity of 0.908 at 1400 °C, owing to the smaller band gap energy and the distortion of Mo4.8Si3C0.6. Moreover, high thermal shock resistance was validated, as no emissivity degradation or obvious spalling of coating was found and only a few microcracks could be observed in the surface after 50 thermal cycles with water-quenching from 1300 °C to 25 °C. •A high infrared emissivity MoSi2/SiC coating was deposited by atmospheric plasma spraying (APS).•The coating showed relatively high total emissivity of 0.908 in 0.76–2.5 μm at 1400 °C.•Smaller band gap energy and distortion of Mo4.8Si3C0.6 were the main enhancing mechanisms.•The coating kept intact till 50 cycles by water-quenching from 1300 °C to 25 °C.