修复损伤叶片熔覆涂层热腐蚀行为  

Hot corrosion behavior of cladding layer for repairing blade

作　　者：胡滨[1] 胡芳友[1] 管仁国[2] 黄旭仁[1] 

机构地区：[1]海军航空工程学院青岛校区,青岛266041 [2]东北大学材料与冶金学院,沈阳110004

出　　处：《中国有色金属学报》2013年第8期2251-2258,共8页The Chinese Journal of Nonferrous Metals

基　　金：中国博士后科学基金项目(20110491882);国家优秀青年科学基金项目(51222405);国家自然科学基金重点项目(51034002)

摘　　要：为研究激光熔覆技术修复某定向凝固航空叶片,采用Nd:YAG脉冲激光器在定向凝固DZ22基体表面熔覆两种自配镍基合金粉末,研究基体和熔覆层在1 000℃高温环境中涂覆Na2SO4(质量分数,75%)+NaCl(质量分数,25%)混合盐饱和水溶液的热腐蚀行为。结果表明:基体单位面积质量的变化量明显高于熔覆层腐蚀试样单位面积质量的变化量;在高温腐蚀开始阶段,腐蚀速度较快;达到一定时间后,腐蚀变缓,速率保持恒定;熔覆层的抗高温腐蚀性能优于基体材料的抗高温腐蚀性能;基体表面氧化物包括Al2O3、Cr2O3、TiO2和WO2等;粉末D熔覆层的抗高温腐蚀能力优于粉末A熔覆层的;氧化层结构复杂,由氧化物、碳化物和氯化物混合生成;熔覆层表面析出相含有Hf,以碳化物的形式析出;熔覆粉末在熔凝过程中和基体材料之间存在着熔质对流,使得熔覆层与基体形成良好的冶金结合。In order to repair a directionally solidified aero blade, laser cladding on DZ22 substrate using two kinds of Ni-based alloy powder by Nd：YAG laser was carried out. The hot corrosion behaviors of the substrate and the cladding layer in Na2SO4（75%, mass fraction）＋NaCl（25%, mass fraction） at 1 000℃were investigated. The results show that, the mass variation per unit area of the substrate is obviously higher than that of the cladding layers. The corrosion rate is high at the beginning of the hot corrosion, the rate is low after a certain time, the hot corrosion resistant performance of the cladding layers is better than that of the substrate, the oxides of the substrate includes Al2O3, Cr2O3, TiO2 and WO2. The hot corrosion resistant performance of the cladding layer of the powder D is better than that of the powder A. The products include oxides, carbides and chlorides. Hf is precipitated in the cladding layer with the form of carbides, the convection exists between the cladding powder and the substrate in the fused process. The fine metallurgical bonding is formed between the cladding layer and the substrate.

关 键 词：热腐蚀 激光熔覆 叶片 定向凝固 显微组织 

分 类 号：O532.25[理学—等离子体物理]