Evaluation of three kinds of MCrAlY coatings produced by electrospark deposition  

微弧火花沉积3种不同MCrAlY涂层的组织与性能评价（英文）

作　　者：谢玉江[1,2] 王德[2] 王明生[1] 叶威[1] 

机构地区：[1]中国科学院金属研究所,腐蚀与防护国家重点实验室,沈阳110016 [2]江西省科学院应用物理研究所,南昌330029

出　　处：《Transactions of Nonferrous Metals Society of China》2016年第6期1647-1654,共8页中国有色金属学报（英文版）

基　　金：Project(50901081)supported by the National Natural Science Foundation of China

摘　　要：Three kinds of MCrAlY coatings with different aluminum contents （5%, 8%, 12%） were prepared by electrospark deposition （ESD）, their microstructure and oxidation behavior were studied by SEM and XRD. The results showed that the phase composition of the coatings changed from single γ-Ni to γ-Ni＋β-NiAl hypoeutectic to γ-Ni＋β-NiAl hypereutectic with increasing aluminum content, and their solidification morphologies changed from cluster of cellular structure to cellular dendrites to coarse dendrites with secondary arms. When exposed at 1000 ℃, the coatings with higher Al content had a stronger tendency to form θ-Al2O3 in the initial several hours. After 100 h of oxidation, a dense and adherent α-Al2O3 scale formed on all of the three coatings but the thickness of α-Al2O3 scale and the amount of remaining θ-Al2O3 increased with increasing Al content. These results revealed different characteristics of ESD MCrAlY coatings which could provide scientific guidance for industrial application.应用微弧火花沉积工艺(ESD)制备了3种不同Al含量(5%,8%,12%)的MCrAlY涂层,并采用SEM和XRD比较研究了显微组织和高温氧化行为。结果表明:随Al含量的增加,涂层的相组成由γ-Ni固溶体变成γ-Ni+β-Ni Al亚共晶,再变成γ-Ni+β-Ni Al过共晶,而相应的凝固组织也由胞状结构团簇变成胞状枝晶再变成带有二次枝晶臂的粗大枝晶。当暴露在1000°C下时,Al含量越高,涂层形成θ-Al2O3的趋势越明显。当氧化时间达到100 h后,所有涂层表面都生成致密且结合良好的α-Al_2O_3氧化层,但当Al含量升高,α-Al_2O_3氧化层厚度和残余θ-Al_2O_3含量都随之增加。

关 键 词：MCRALY electrospark deposition MICROSTRUCTURE oxidation behavior 

分 类 号：TG174.4[金属学及工艺—金属表面处理]