莫来石/SiO2复合涂层的制备及微观组织研究  

Preparation and Microstructure of Mullite/SiO_2 Composite Coating

作　　者：安宇龙[1,2] 陈建敏[1] 周惠娣[1] 魏家俊 

机构地区：[1]中科院兰州化学物理研究所固体润滑国家重点实验室,兰州730000 [2]中国科学院北京研究生院,北京100049 [3]甘肃紫鑫矿业煤化工有限公司,兰州730000

出　　处：《表面技术》2010年第5期1-3,76,共4页Surface Technology

基　　金：国家自然科学基金委创新研究群体科学基金资助项目(50421502)

摘　　要：以天然红柱石为原料,采用高温煅烧使其发生莫来石化转变,然后经喷雾造粒、热处理,得到热喷涂用球形莫来石/SiO2复合粉末。采用大气等离子喷涂工艺在1Cr18Ni9Ti不锈钢上喷涂莫来石/SiO2粉末制得涂层,对涂层的微观组织、硬度和相成分进行了分析。研究结果表明:天然红柱石粉末莫来石化后,其相组成主要为莫来石和游离态SiO2;喷雾造粒粉末在1 000℃热处理后,松装密度得到改善;涂层具有良好的微观形貌,表面显微硬度较高,主要由莫来石、石英和非晶玻璃相构成。Natural andalusite powders as raw material were heated at high temperature in air allowing mullitization.The resultant mullitized powder was spray-dried and heat treated to attain spherical mullite/SiO2 composite powder.The mullite/SiO2 composite powder was then plasma sprayed onto stainless steel（1Cr18Ni9Ti） to form coatings.The microstructural,microhardness and phase structure of as-sprayed mullite coatings were analysed.Results show that the mullitized andalusite powder consists of mullite and a small amount of free SiO2.The apparent density of spray-dried powders is improved after thermal treatment at 1 000 ℃.The as-sprayed coating has fine microstructure and higher microhardness.The phase component of as-sprayed coating consistes of crystalline mullite,quartz and amorphous glass phase.

关 键 词：红柱石 莫来石 喷雾干燥 大气等离子喷涂 

分 类 号：TG174.442[金属学及工艺—金属表面处理]