镍基铸造高温合金Mar-M247的高温氧化行为  

High Temperature Oxidation Behavior of Cast Ni-Based Superalloy Mar-M247

作　　者：潘苗苗 高振桓 巩秀芳[2,3] 隆彬 杨功显[2,3] 宋小龙 PAN Miao-miao;GAO Zhen-huan;GONG Xiu-fang;LONG Bin;YANG Gong-xian;SONG Xiao-long(State Key Laboratory for Mechanical Behavior of Materials,Xi'an Jiaotong University,Xi'an 710049,Shaanxi,China;State Key Laboratory of Long-Life High Temperature Materials,Deyang 618000,Sichuan,China;Dongfang Electric Corporation Dongfang Turbine Co.,Ltd.,Deyang 618000,Sichuan,China)

机构地区：[1]西安交通大学金属材料强度国家重点实验室,陕西西安710049 [2]长寿命高温材料国家重点实验室,四川德阳618000 [3]东方电气集团东方汽轮机有限公司,四川德阳618000

出　　处：《铸造》2020年第8期797-802,共6页Foundry

基　　金：四川省科技计划资助项目(2018JY0391)。

摘　　要：研究了某工业重型燃气轮机叶片材料Mar-M247合金在800℃和900℃的恒温氧化行为。结果表明,Mar-M247合金在两个试验温度下的氧化动力学符合抛物线规律,并且均为完全抗氧化级,Mar-M247合金的氧化激活能约为268.4 kJ·mol^-1,氧化过程主要是由Cr2O3的形成来控制。借助场发射扫描电镜和能谱对氧化层组成进行分析,结果表明,合金在800℃下氧化100 h后,氧化膜最外层为Cr2O3,中间层为TiO2以及少量Ta2O5与HfO2,内层为钉楔状的氧化物Al2O3;而900℃下氧化100 h后,氧化膜最外层是NiO和CoO,中间层为相对致密的Cr2O3和少量小块状不连续的TiO2、Ta2O5与HfO2,内层为尺寸较大的钉楔状氧化物Al2O3。内氧化区和贫化层区域随着氧化温度的升高而扩大。The oxidation behavior of the Mar-M247 alloy used as the blade material in the industrial heavy-duty gas turbine has been studied at 800 ℃ and 900 ℃. The results indicate that the oxidation kinetics curves of cast Mar-M247 alloy at 800 ℃ and 900 ℃ follow the parabolic law, there with the grade of oxidation resistance of the alloy has been given. The oxidation activation energy of Mar-M247 alloy is about 268.4 kJ·mol-1, and the oxidation process is mainly controlled by the formation of Cr2O3. The oxide scales were examined by a field emission scanning electron microscopy(FESEM) equipped with an energy dispersive spectroscopy(EDS). Experimental results show that at 800 ℃, the outermost layer of the oxide scales is Cr2O3, and the intermediate layer is TiO2, as well as a small amount of Ta2O5 and HfO2. Whereas, the internal layer is Al2 O3, which exhibits a wedge-shaped morphology. In contrast, at 900 ℃, the outermost layer of the oxide scales is NiO and CoO, and the intermediate layer is Cr2O3, as well as a small amount of TiO2. Whereas, the internal layer is Al2O3. As the oxidation temperature increases, the depth of the inner oxidation zone increases and the area of the depleted layer expands.

关 键 词：Mar-M247合金 氧化动力学 氧化层 内氧化 贫化层 

分 类 号：TG146.15[一般工业技术—材料科学与工程]