原子氧对ZrB_2-SiC陶瓷复合材料氧化行为的影响  

Effect of atomic oxygen on oxidation behavior of ZrB_2-SiC ceramic composite materials

作　　者：金华[1] 孟松鹤[1] 解维华[1] 曾庆轩[1] 牛家宏 

机构地区：[1]哈尔滨工业大学复合材料与结构研究所,哈尔滨150001

出　　处：《复合材料学报》2013年第S1期199-204,共6页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(11272107);国家自然科学基金集成项目(91016029;91216302)

摘　　要：利用实验室设备模拟了高速飞行过程中端头材料经受的高温、低压及氧原子为主的等离子环境,研究了典型端头候选复合材料ZrB2-20%vol SiC陶瓷在40Pa、1400~1700℃原子氧和分子氧环境下的氧化行为,通过XRD、SEM以及XPS测试方法,对比分析了两种环境下材料表面的氧化产物、化学键能、微观组织以及氧化层结构。结果表明材料在原子氧环境下的氧化程度明显大于分子氧环境,在相同温度和压力下,材料表面完全氧化,形成ZrO2层、SiC耗尽层、不完全反应层以及未反应层的四层结构,氧化层厚度约为分子氧环境下的1.6倍。研究表明,低压原子氧环境可显著提高氧化速率,降低材料在低压条件下的抗氧化性能。The oxidation behavior of ZrB2-20% vol SiC ceramic composites,which is typically used as the potential composite materials of nose,in the ambience pressure of 40Pa and temperatures between 1400and 1700℃ of the atomic and molecular oxygen environment were studied.The practical situation of tip materials exposed in the plasma of high temperature,low pressure and mainly the oxygen atomics during the process of high-speed flight was simulated with the laboratory apparatus.Comparative analysis of oxidation product,chemical-bond energy, microstructure and oxide layer structure were conducted by XRD,SEM and XPS measurements.It showed that oxidation in atomic oxygen was significantly greater than molecular oxygen.With the same temperature and pressure,the material surface was fully oxidized in atomic oxygen.The formation of four-layer structures of ZrO2, SiC depletion layer,incomplete reaction layer and unreacted layer could be found.The thickness of oxidation layer in atomic oxygen was as 1.6times as in molecular oxygen.The research shows that low-pressure atomic oxygen environment can increase oxidation rate significantly so that decrease the low-pressure oxidation resistance.

关 键 词：ZrB2-SiC陶瓷复合材料 原子氧 氧化 微观结构 氧化层结构 

分 类 号：TB332[一般工业技术—材料科学与工程]