Effect of space travel velocity of spray gun on temperature field of Mo/8YSZ composite coating prepared by plasma spraying process

• Main Authors: PANG Ming, ZHANG Xiaohan, LIU Guang
• Format: Article
• Language: zho
• Published: Journal of Aeronautical Materials 2020-02-01
• Series: Journal of Aeronautical Materials
• Subjects: plasma spraying; functionally gradient thermal barrier coatings; space travel velocity of spray gun; temperature field; finite element
• Online Access: http://jam.biam.ac.cn/article/doi/10.11868/j.issn.1005-5053.2019.000038
• ISSN: 1005-5053; 1005-5053

In order to break through the technical bottleneck of traditional metal-ceramic double-layer thermal protective coating which is easy to peel in high temperature environment, the influence of the space travel velocity of the spray gun on temperature field in time domain and space domain of the Mo/8YSZ composite coating was studied. Using ANSYS finite element analysis software, a numerical model for preparing Mo/8YSZ functionally graded thermal barrier coatings by plasma spraying was established, and the thermal properties of the material at different temperatures and the latent heat of phase change of the material were also considered in the model. By analyzing the temperature and temperature gradient of the sprayed component under the different space travel velocities of the spray gun, it is found that at the same time of the spraying process, the greater the travel velocity of the spray gun, the less time the spray gun interacts with the component per unit length, the smaller the maximum temperature value of the component, the higher the uniformity of the temperature distribution on the upper surface of the component, and the smaller the maximum temperature gradient value of the component. The first deposited coating has a preheating effect on the post-deposited coating, and the maximum temperature value of the substrate exhibits a "stepped" increase trend. As the thickness of the coating increases, the thermal resistance of the coating increases, and the fluctuation of the substrate temperature gradually decreases. The temperature gradient of the component can be further reduced by adjusting the travel velocity of the spray gun of each coating, and the temperature gradient of the component can be minimized when the spraying is undertaken in accordance with the sequence of maximum bonding layer, transition layer and minimum ceramic layer.