Abstract: The electronic structure and optical properties of Cr and Al2O3 were analyzed qualitatively by calculating their band structure, density of states and dielectric function based on first－principles. The extinction coefficients of Cr and Al2O3 were fit with the dielectric function, and their effects on the absorptivity and emissivity were studied. Based on the calculating results, we designed the experimental scheme that preparing the Cr-Al2O3 metal－ceramics films by plasma spraying process, and the performance of which were tested and analyzed.

Key words: dielectric function, extinction coefficient, absorptivity, selective