等离子喷涂常规和纳米ZrO_2-7%Y_2O_3热障涂层的热腐蚀性能  

Hot Corrosion Resistance of Plasma-sprayed Conventional and Nano-structured ZrO_2-7%Y_2O_3 Thermal Barrier Coating

作　　者：王东生[1,2] 田宗军[1] 沈理达[1] 黄因慧[1] 

机构地区：[1]南京航空航天大学机电学院,江苏南京210016 [2]铜陵学院机械工程学院,安徽铜陵244000

出　　处：《热加工工艺》2014年第8期156-160,共5页Hot Working Technology

基　　金：国家自然科学基金资助项目(51205198;21171131);中国博士后科学基金面上资助项目(2012M511266);安徽省自然科学基金资助项目(1208085QE84);江苏省博士后科研资助计划资助项目(1102052C);安徽省高等学校省级优秀青年人才基金资助重点项目(2012SQRL190ZD)

摘　　要：采用等离子喷涂技术制备了常规和纳米MCrAlY/ZrO2-7%Y2O3(质量分数)双层系统热障涂层。比较了两种涂层的微观结构和850℃下75%Na2SO4+25%NaCl(质量分数)混合熔盐中耐热腐蚀性能,并探讨了涂层的热腐蚀破坏机理。结果表明,等离子喷涂常规和纳米热障涂层都为典型的层状堆积结构,但与常规涂层相比,纳米团聚体粉末喷涂过程中熔化充分,其涂层孔隙率低,组织更致密。两种涂层的热腐蚀破坏都是稳定剂Y2O3的消耗而引起的部分四方相转化为单斜相的马氏体相变,但总体上纳米热障涂层本身的热腐蚀程度要小于常规涂层,其对金属粘结层及基体的保护也更好。Conventional and nano-structured MCrA1Y/ZrO2-7%Y203 （mass fraction） double-layer system thermal barrier coating were fabricated by plasma spraying process. The microstructure and hot corrosion resistance of the two kinds of coating in 5%Na2SO4＋25%NaC1 （mass fraction） molten salt at 850 ℃ were compared. Meanwhile, the hot corrosion failure mechanisms of the coating were discussed. The results show that the plasma-sprayed conventional and nano-structured thermal bar rier coating have typical lamellar stacking characteristic. Due to fully melted of nano-structured agglomerated powders during plasma spraying, the nano-structured coating shows lower porsity and higher compactness than conventional one. Owing to the consumption of stabilizer Y2O3, the hot corrosion failure of the Coating is dominated by martensitic transformation, where partially tetragonal ZrO2 transforms into monoclinic ZrO2. The nano-structured coaitng has a better hot corrosion resistance than the conventional coating, and the corrosion of ceramic coating and the protection to metal bonding and substrate is also better.

关 键 词：等离子喷涂 热障涂层 纳米涂层 热腐蚀性能 

分 类 号：TG174.44[金属学及工艺—金属表面处理]