Preparation and thermal shock resistance of solar thermal absorbing corundum ceramics for concentrated solar power

Abstract

AbstractThe absorptivity of solar thermal absorber materials affects the heliothermal conversion efficiency of concentrated solar power systems. The solar absorbing ceramics were prepared by the fixed mixture of bauxit, Fe2O3, and TiO2 with adding CuO in different percentages. The absorptivity and thermal shock resistance with the effect of adding CuO in different percentages were studied. Fe2O3 and TiO2 have excellent optical properties, and CuO decreases the material's band gap to boost the electronic transition and increase the material absorptivity. The results showed that the material is sintered at 1380°C with an excellent absorptivity of 94.00% in the spectrum range of 0.3–2.5 μm, and the bending strength is 132.94 MPa. The bending strength was increased by 21.07% after 30 thermal shock cycles (1000°C‐room temperature, air cooling). The liquid phase facilitates the synthesis of hercynite with excellent high temperature properties. The hercynite improves the thermal shock resistance of the material.