SiC 抗氧化机制电弧加热试验

介绍了在电弧加热器上进行的SiC的抗氧化机制研究试验,根据SiC的主动、被动氧化机制,调试出相应试验条件并进行了模型试验.结果表明,SiC在一定的氧分压环境中,表面温度低于转捩温度时,会在表面形成SiO2薄膜,阻止氧向防热层内部扩散,降低了碳同氧的反应程度,阻止了基体碳的烧蚀;当表面温度高于转捩温度时材料发生主动氧化,材料表面发生烧蚀.

Oxidation Resistance Mechanism of SiC in Arc Heater

The experiment of oxidation resistance mechanism for silicon carbide in arc heater is introduced. Test
conditions were confirmed according to active and passive oxidation mechanism of the SiC composite material. The results indicated that the silicon dioxide (SiO2) film appeared on the surface of silicon carbide when the surface temperature is less than the transition temperature;the film prevented the ablation of the materials because that decreased the reaction between oxygen and carbon materials. On the other hand,the silicon carbide surface ablated when the surface temperature is higher than the transition temperature.