A novel ultra-high-temperature oxidation protective MoSi2-TaSi2 ceramic coating for tantalum substrate |
| |
| Authors: | Zhenyang Cai Daxu Zhang Xinxiang Chen Yuntong Huang Yuqing Peng Canhui Xu Siyu Huang Rong Pu Sainan Liu Xiaojun Zhao Lairong Xiao |
| |
| Affiliation: | 1. School of Materials Science and Engineering, Central South University, Changsha 410083, Hunan, China;2. Center for Mineral Materials, School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, Hunan, China;3. Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, 621900, Sichuan, China;4. Key Laboratory of Nonferrous Metal Materials Science and Engineering, Ministry of Education, Central South University, Changsha 410083, Hunan, China;5. Department of Materials Engineering, Rensselaer Polytechnic Institute, Troy, New York, 12180, USA |
| |
| Abstract: | To protect refractory metal against oxidation at ultra-high temperatures, a MoSi2-TaSi2 ceramic coating was prepared on a pure tantalum (Ta) substrate using a novel three-step process, which included dip-coating with a molybdenum slurry, vacuum sintering, and halide-activated pack cementation (HAPC). The original coating had a MoSi2-TaSi2 double-layer structure from the surface to the substrate. After oxidation at 1700°C for 8 h in air, the coating exhibited a complex multi-layer structure composed of SiO2-Mo5Si3-MoSi2-(Mo,Ta)5Si3-TaSi2-Ta5Si3 from the outer layer to the inner layer, due to the high-temperature phase transition and diffusion of Si and O. The coating effectively protected the Ta substrate at 1700°C for 12 h without failure, thereby demonstrating great improvement to its service life in an ultra-high-temperature aerobic environment. The protective effect was attributed to the integrity of the ceramic coating and the formation of a dense, uniform SiO2 film that effectively lowered the inward oxygen diffusion rate. |
| |
| Keywords: | Corresponding author at: School of Materials Science and Engineering Central South University Changsha 410083 Hunan China Tantalum Silicide ceramic coating Oxidation Slurry sintering Pack cementation |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
