等离子喷涂纳米结构Al2O3基涂层的性能分析.docVIP

  等离子喷涂纳米结构 Al2O3 基涂层的性能分 析# 杨勇，阎殿然，董艳春，陈学广，褚振华，王磊，刘哲，张建新，何继宁* 5 10 15 20 25 30 35 40 45 （河北工业大学 材料科学与工程学院, 天津 300132） 摘要：采用等离子喷涂技术在金属表面制备纳米结构 Al2O3 基涂层，研究等离子喷涂功率对 纳米涂层显微组织结构和性能的影响规律，以及涂层的干滑动摩擦磨损性能。结果表明，随 着喷涂功率的增大，涂层中 α-Al2O3 相有所减少，涂层中孔隙逐渐减少、致密度提高。等离 子喷涂纳米结构 Al2O3 基涂层中包括完全熔化区和半熔化区两部分典型显微组织，随着喷涂 功率的增大，涂层中完全熔化区的比例越大。纳米涂层的硬度随着喷涂功率的升高呈现先升 高后略有下降的趋势，不同喷涂功率制备的纳米涂层的显微硬度都高于常规微米涂层。纳米 涂层的断裂韧性比常规微米涂层提高 1/4 左右。两种涂层的摩擦系数均随载荷增加而下降， 纳米涂层的摩擦系数低于微米涂层。相同条件下纳米涂层的磨损失重低于微米涂层。常规微 米涂层脆性较高且层间结合强度较低，主要表现为脆性断裂或层状剥落；而纳米涂层具有双 态分布结构和细晶组织，其韧性较高，故耐磨性较好。 关键词：Al2O3-TiO2；纳米结构涂层；等离子喷涂；显微组织；性能 中图分类号：TG174.4 Property characterizations of plasma sprayed nanostructured Al2O3 matrix coating Yang Yong, Yan Dianran, Dong Yanchun, Chen Xueguang, Chu Zhenhua, Wang Lei, Liu Zhe, Zhang Jianxin, He Jining (School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300132) Abstract: Nanostructured Al2O3 matrix coatings were prepared by plasma spraying. The effects of spraying powers on the microstructure and properties of the coatings were investigated, and the dry sliding wear behavior of the coatings were investigated. The results showed that with the increase of the spraying powers, α-Al2O3 in the nanostructured coating was reduced and the pores were decreased. The nanostructured Al2O3 matrix coatings prepared by plasma spraying contained two representative structures, which were the fully-melted (FM) region and the partially-melted (PM) region. With the increase of the spraying powers, the FM region was increased. With the increase of the spraying powers, the microhardness of the nanostructured coatings was increased first and then decreased. The microhardness of the nanostructured coatings was higher than that of the microstructured coatings. The fracture toughness of the nanostructured coatings was 25% higher than that of the microstructured coatings. The coefficient of friction of the two coatings decreased with the increase of the wear loads. The coefficients of friction of