Microstructure and oxidation resistance of a YSZ modified silicide coating for Ta-W alloy at 1800 °C. (October 2018)

• Record Type: Journal Article
• Authors: Cai, Zhenyang; Zhao, Xiaojun; Zhang, Daxu; Wu, Yonghuang; Wen, Jianxi; Tian, Gengyu; Cao, Qinxuan; Tang, Xinyang; Xiao, Lairong; Liu, Sainan
• Is Part Of: Corrosion science. Volume 143(2018)
• Page Start: 116
• Page End: 128
• Publication Date: 2018-10
• Subjects: A. Metal coatings -- A. Intermetallic -- B. EPMA -- B. TEM -- B. Thermal cycling -- C. Oxidation; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2018.08.007
• Languages: English
• ISSNs: 0010-938X

Abstract

Graphical abstract: Highlights: A Si-Mo-YSZ coating was prepared on Ta-W alloy by slurry reaction sintering method. The coated sample remained intact after oxidation at 1800 °C for 10 h. The coating withstood 218 shock heating cycles from room temperature to 1800 °C. The excellent performance was attributed to the dense SiO2 -ZrO2 -ZrSiO4 scale. Microstructure evolution and failure mechanism of the coating were analyzed. Abstract: To develop an ultra-high temperature resistant coating for a reusable thermal protection system, a YSZ-modified Si-Mo coatings were prepared on Ta-10 W alloy by slurry reaction sintering method. The coating had a MoSi2 -ZrSi2 -SiO2 outer layer and a TaSi2 -WSi2 inner layer. The coated sample remained intact after oxidation at 1800 °C for 10 h, while the untreated alloy was pulverized after 6 min. The coating withstood more than 200 shock heating cycles from room temperature to 1800 °C. Its outstanding oxidation resistance is attributed to its thermal matching with the alloy and formation of protective SiO2 scale containing high-melting ZrSiO4 and ZrO2 .