碳/碳复合材料MoSi2/SiC涂层在动态氧化环境下的性能研究

为了考察MoSi₂/SiC防氧化涂层体系在动态氧化环境下的防护能力,对碳/碳复合材料MoSi₂/SiC涂层试样在1100~1500℃下进行了高温燃气高质流冲刷环境下的氧化试验。结果表明,在1100~1500℃的燃气动态环境下,具有稳定的氧化失重速率,氧化失重曲线近似呈直线关系,氧化失重和氧化失重速率均随着氧化温度的升高而降低,表现出该涂层抗高质流冲刷和氧化的能力随温度的升高而提高,在该温度区间内,随着温度的升高,具有更优异的抗氧化和抗高质流冲刷的能力。

DYNAMIC ANTI-OXIDATION BEHAVIOUR OF MoSi2/SiC COATING SYSTEM FOR CARBON-CARBON COMPOSITES

In the present work, the dynamic anti-oxidation behavior and damage mechanism of MoSi2-SiC multilayer ceramic coating for carbon-carbon composites were investigated experimentally at various temperatures of 1100~1500℃ under the test for gas jet washout. Experimental data of dynamic oxidation show that the mass loss of MoSi2/SiC coated carbon-carbon composites decreases, and the ability of oxidation resistance is enhanced with raising the gas temperature up to 1500℃. The mechanism of dynamic oxidation and the concept of the integrity of the coating layer are explained from the theory of mass transportation and the damage of gas jet washout. In this respect, the dynamic oxidation behaviour differs from the static oxidation. The results show that the MoSi2/SiC ceramic coating for carbon-carbon composites can provide dynamic oxidation protection to C/C composites at temperatures up to 1500℃ in a gas jet environment.