Affiliation:
1. Kunming Institute of Precious Metals, Kunming 650106, China
Abstract
In this study, a HfO2 coating was developed on an Ir matrix using a customized open-tube airflow, cold-wall chemical vapor deposition instrument. The preparation process and structure of the as-prepared coating were investigated to gain insights into its characteristics. The HfO2 coating effectively prevents direct contact between Ir and O, leading to a reduction in the oxidation rate of Ir. Furthermore, defects such as micropores and cracks generated during sealed oxidation erosion contribute to Ir’s decelerated oxidation failure. The as-prepared HfO2 coating exhibits low thermal conductivity and a high heat radiation rate, reducing the coating’s surface temperature. These characteristics significantly enhance adversity tolerance and increase the working temperature of the coating. Moreover, the as-prepared HfO2 coating can serve as a diffusion barrier, blocking both the direct contact of O with the Ir coating and the diffusion of other elements to the Ir coating. As a result, the rates of diffusion of other elements to the Ir coating are reduced.
Funder
National Science Foundation of China
Scientific and Technological Project of Yunan Precious Metals Laboratory
Yunnan Science and Technology Projects
Reference37 articles.
1. Schütze, M. (2000). Materials Science and Technology: A Comprehensive Treatment, John Wiley & Sons, Ltd.
2. Thermal Barrier Coatings—A State of the Art Review;Thakare;Met. Mater. Int.,2021
3. Biaglow, J. (1998). 34th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit, American Institute of Aeronautics and Astronautics.
4. A Long Duration and High Reliability Liquid Apogee Engine for Satellites;Liu;Acta Astronaut.,2004
5. Mechanical Properties and Thermal Shock Resistance of Rhenium Coating in Iridium/Rhenium/Carbon-Carbon Composites;Guo;Procedia Eng.,2015