中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 31 No. 8 August 2021 |
(Naval Architecture and Port Engineering College, Shandong Jiaotong University, Weihai 264200, China)
Abstract:Nickel-based superalloys with and without Co by partial replacement of W were prepared using double vacuum melting. A comparison of the oxidation in air and hot corrosion behaviors under molten 75wt.%Na2SO4+ 25wt.%NaCl at 900 °C were systematically investigated. The results showed that partial replacement of W with Co promoted the formation of chromia scale and consequently decreased the oxidation rate. Besides, the addition of Co also retarded the internal oxidation/nitridation of Al and consequently promoted the growth of Al2O3 scale, which further decreased the scaling rate and improved the adhesion of scale. Moreover, the addition of Co also further improved the hot corrosion resistance under molten Na2SO4-NaCl salts.
Key words: nickel based superalloys; oxidation; hot corrosion; spallation resistance