Non-calcining process for CuAlO2 and CuAl0.9Ca0.1O2 ceramics

Synthesis of CuAlO2 and CuAl0.9Ca0.1O2 ceramics for thermoelectric application using a reaction-sintering process was investigated in this study. Without any calcination involved, the mixture of raw materials was pressed and sintered directly. Some peaks of remained Al2O3 were detected in CuAlO2. CaAl4O7 and CuO were detected in CuAl0.9Ca0.1O2. Density values 2.83–3.04 g/cm3 were found in CuAlO2 pellets sintered at 1350 °C. In CuAl0.9Ca0.1O2 ceramics, density values 3.10–3.31 g/cm3 were found in pellets sintered at 1350 °C. Thin polygonal grains were observed in CuAl0.9Ca0.1O2. The reaction-sintering process has proven a simple and effective method in preparing CuAlO2 and CuAl0.9Ca0.1O2 ceramics for thermoelectric application.