摘要
采用增重法,研究了不同Mn含量的Hastelloy N合金在700℃/200 h内下的恒温氧化行为。利用扫描电镜(SEM)、能谱分析仪(EDS)和X射线衍射仪(XRD)分析了不同Mn含量的Hastelloy N合金700℃氧化膜的氧化动力学、形貌、物相组成以及氧化层中元素分布情况。结果表明Hastelloy N合金在700℃氧化动力曲线符合抛物线规律,随着Mn含量的增加氧化增重逐渐减少,氧化膜厚度分别为17.0, 14.8, 12.9, 10.0μm。不同Mn含量的Hastelloy N合金在700℃下的平均氧化速率分别为0.054, 0.050, 0.048, 0.040 g·(m^2·h)^(-1),根据氧化等级评定, 4种合金均属于完全抗氧化等级。氧化层表面皆无明显剥落,氧化膜呈分层现象,其中外层为NiO, Fe_2O_3, NiFe_2O_4等复合氧化物,内层为Cr_2O_3, MoO_2, NiMn_2O_4等氧化物。Mn的添加使氧化膜外层与基体之间生成NiMn_2O_4尖晶石层,阻碍了O元素向内扩散以及金属元素的向外扩散,有效提高了Hastelloy N合金的抗氧化性能。
The isothermal oxidation behavior of Hastelloy N alloy with different Mn contents in air at 700 ℃ for 200 h was investigated by mass gain method. Oxidation kinetics, morphology and component of the oxide scale formed on Hastelloy N alloy were analyzed by means of scanning electron microscopy(SEM), energy dispersive spectrometer(EDS) and X-ray diffraction(XRD). The results showed that the oxidation kinetic curves of Hastelloy N alloy followed parabolic law at 700 ℃, the oxidation weight gain decreased with the increase of Mn content and the thickness of the oxide film was 17.0, 14.8, 12.9 and 10.0 μm, respectively. The oxidation rates of Hastelloy N alloy with different Mn contents at 700 ℃ were 0.054, 0.050, 0.048 and 0.040 g·(m2·h)-1, respectively. The alloys were estimated to be completely antioxidant according to the oxidation rate. The surface of oxidation film was no significant spallation, and the oxide film was layered. The outer oxide film of Hastelloy N superalloy mainly consisted of NiO, Fe2O3 and other oxide composites, the middle layer consisted of Cr2O3, MoO2, NiMn2O4 and other oxides. The addition of Mn could lead to the formation of NiMn2O4 spinel layer between the outer layer of oxide film and the substrate, which hindered the inward diffusion of O and the outward diffusion of metal elements, effectively improving the oxidation resistance of Hastelloy N alloy at 700 ℃.
作者
李建树
郭伟杰
张继祥
陆燕玲
周兴泰
Li Jianshu;Guo Weijie;Zhang Jixiang;Lu Yanling;Zhou Xingtai(College of Mechanotronics and Vehicle Engineering,Chongqing Jiaotong University,Chongqing 400074,China;Department of Nuclear Materials Science and Engineering,Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai 201800,China)
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2019年第2期157-163,共7页
Chinese Journal of Rare Metals
基金
国家自然科学基金项目(51674237)
超轻材料与表面技术教育部重点实验室资助项目资助
作者简介
李建树(1990-),男,山东青岛人,硕士研究生,研究方向:合金材料性能评估,E-mail:lijianshu1122@163.com;通信作者:张继祥,教授,电话:13648314609,E-mail:jixiangzhang@163.com
