The Synthesis and the Thermal Properties of CaZr4(PO4)6 Materials
CaZr4(PO4)6 ceramics were prepared with solid reaction of two-steps method. CaZr4(PO4)6 powders were synthesized by solid-phase reaction with Ca (OH)2, ZrO2 and (NH4)2HPO4 as raw materials. Then the powders precursor were sintered to CaZr4(PO4)6 ceramics with single phase structure at 1400°C for 8 hours. The relative density was measured, the phase structure of the materials synthesized at different temperatures and the average coefficients of thermal expansion were investigated. The results showed that the relative density of CaZr4(PO4)6 ceramics sintered at 1400°C was 93%. The average thermal expansion coefficients was 1.8×10-6/°C from 25°C to 1400°C. The CaZr4(PO4)6 ceramics obtained possesses low thermal expansion property in a broad range of temperatures.