Infrared Radiative Property of Air Plasma Spraying Ysz and Ysz-Al2o3 Thermal Barrier Coatings

Al2O3 as a scattering component was introduced into air plasma spraying thermal barrier coatings (TBCs) to enhance the backward scattering and heat insulation. Compared with YSZ coating, the average transmittance of YSZ-Al2O3 coating with a thickness of 460 μm is reduced from 16.07% to 8.85% and the scattering coefficient is improved by 38.7% (from 12283 to 17042 m-1) which is caused by the higher porosity and the refractive index difference between YSZ and Al2O3 in YSZ-Al2O3 coating. Higher backward scattering results in a reduction of radiation heat flux by 20.8% (from 0.171 to 0.135 MW/m2). The substrate temperature is reduced by 7.3K and the coating surface temperature is reduced up to 11.2 K due to the increased backscattering of incident radiation, thus leads to the improvement of the TBCs thermal insulting efficiency.

Keywords: Infrared radiative property, Thermal barrier coating, absorption and scattering coefficients, temperature distribution, YSZ-Al2O3 coating

Suggested Citation: Suggested Citation

zhang, liuchao and Luo, Fa and Zhou, Yingying and Wang, Chunhai and Nan, Hanyi and Zhang, Qian and Qing, Yuchang and Chen, Qiang, Infrared Radiative Property of Air Plasma Spraying Ysz and Ysz-Al2o3 Thermal Barrier Coatings. Available at SSRN: https://ssrn.com/abstract=4257811 or http://dx.doi.org/10.2139/ssrn.4257811