900℃加热后热喷涂FeCrAl/AlSi复合涂层组织变化  

Microstructure evolution of thermal sprayed FeCrAl/AlSi composite coating after heating at 900 ℃

作　　者：张忠礼[1] 沈威威[1] 杨国强[1] 谢天男[1] 

机构地区：[1]沈阳工业大学材料科学与工程学院,沈阳110870

出　　处：《沈阳工业大学学报》2013年第4期400-406,共7页Journal of Shenyang University of Technology

基　　金：沈阳市科技攻关资助项目(F-10-011-2-00)

摘　　要：为开发一种经济可靠的高温防护涂层,采用电弧喷涂方法在低碳钢表面制备FeCrAl/AlSi复合涂层,并对复合涂层试件进行900℃温度下的2 400 h加热,以考察其高温氧化表现和微观组织变化.实验结果表明:复合涂层中抗氧化元素的相互配合很好地保护了基体金属.900℃加热3 h,防护涂层表面以及内部的氧化物以Al2O3为主,涂层/基体界面两侧形成Cr元素的扩散带.经过2 400 h加热后,复合涂层外表面氧化物层增厚,涂层/基体界面原位生成铬的氧化物,界面基体金属一侧存在约200μm宽的Cr元素扩散带.In order to develop an economical and reliable high-temperature protective coating, the FeCrAl/AlSi composite coating on the surface of mild steel was prepared with arc spraying method. The specimens with composite coating were heated at 900 ℃ for 2 400 h to investigate their high-temperature oxidation characteristics and microstructure evolution. The experimental results show that the oxidization-resistant elements in the composite coating cooperate well with each other, which can provide a good protection for the base metal. After heating at 900 ℃ for 3 h, the oxides on the surface or inside the protective coating are mainly Al2O3, and the diffusion bands of Cr element form at both sides of coating/substrate interface. After heating for 2 400 h, the oxide layer on the outer surface of composite coating becomes thicker. Furthermore, some Cr-containing oxides are generated on the coating/substrate interface by in-situ reaction. The diffusion bands of Cr element with a width of about 200 μm exist at the metal substrate side of interface.

关 键 词：高温防护 高温氧化 电弧喷涂 铁铬铝 铝硅合金 复合涂层 微观组织结构 扩散带 

分 类 号：TG174.442[金属学及工艺—金属表面处理]