炭/炭复合材料SiC/SiC+mullite/mullite涂层制备及其高温性能  

Preparation and anti-oxidation property of SiC/SiC+mullite/mullite coating on C/C composites

作　　者：马超[1] 李贺军[1] 史小红[1] 张正中[1] 吴恒[1] 孙粲[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,西安710072

出　　处：《材料科学与工艺》2013年第1期79-85,共7页Materials Science and Technology

基　　金：国家自然基金资助项目(50832004;50902111);西北工业大学基础研究基金资助项目(GBKY1021)

摘　　要：为提高炭/炭复合材料的防氧化性能,采用包埋法与超音速等离子喷涂法相结合,在其表面制备了SiC/SiC+mullite/mullite多层防氧化涂层.外涂层主要组成是莫来石(mullite)相.对涂层试样进行了1 500℃恒温氧化和1 500℃～室温热震测试.实验结果表明,涂层试样经1 500℃恒温氧化150 h后,失重率仅为0.26%;经1 500℃～室温15次热震后,失重率仅为0.25%,显示出较优异的防氧化、抗热震性能.莫来石(mullite)具有良好的耐高温性能、低的氧扩散率,且SiC涂层氧化生成的SiO2在高温下能够愈合裂纹等缺陷,这是SiC/SiC+mullite/mullite涂层较好防氧化能力的主要原因.To improve the oxidation resistance of carbon/carbon（C/C） composites,a SiC/SiC＋mullite/mullite coating was prepared on the surface of C/C composites by solid phase infiltration and supersonic plasma spraying.The outer coating was mainly composed of mullite phase.The isothermal oxidation test at 1 773 K and thermal shock test between 1 773 K and room temperature were carried out.The results showed that after 150 h oxidation at 1 500 ℃,the weight loss of the coated C/C composite was only 0.26%.The coated specimens also exhibited good thermal shock resistance,with a mass loss of 0.25% after 15 thermal shocks between 1 500 ℃ and room temperature.The excellent anti-oxidation property of the coating was mainly attributed to high thermal stability and low oxygen diffusion rate of mullite.Besides,SiO2 could fill in the cracks in mullite coating at high temperature,which was benefit to improve the oxidation resistance.

关 键 词：莫来石 超音速等离子喷涂 防氧化 炭 炭(C C)复合材料 

分 类 号：TB332[一般工业技术—材料科学与工程]