金属钼表面Mo-Si-N-B涂层的抗高温氧化性能研究

Study on High-temperature Oxidation Resistance of Mo-Si-N-B Coating on Mo substrate

在金属钼表面制备了Mo-Si-N-B涂层,利用SEM和XRD分析研究了涂层的微观结构和物相组成,并评价了涂层在1 450℃大气环境下的抗氧化性能。结果表明:涂层由MoSi2相、Si3N4和Mo2B5相组成,涂层内部致密且与基体结合紧密;高温氧化时,涂层表面生成致密硼硅玻璃氧化膜,其稳定抗氧化时间达100 h;高温下由于氧化膜的挥发和涂层的"退化"导致涂层失效。

Mo-Si-N-B coating was fabricated on Mo substrate. The microstructures and phase composition of the coatings were analyzed as well as the oxidation resistance at 1 450 ℃ in air was measured by SEM and XRD. The results show that Mo-Si-N-B coating, comprised of MoSi2, Si3N4 and Mo2B5 phases, is compact inside and closely bonded with the substrate. When high-temperature oxidation takes place, a layer of dense oxide film of borosilicate glass forms on the surface of Mo-Si-N-B coating, with the time of stable antioxidation reaching to 100 hours. At a high temperature, the volatilization of the film and the degradation of the coating cause the failure of the latter