Sintering and Properties of Monazite‐Type CePO 4

Monazite‐type CePO 4 powder (average grain size 0.3 μm) was dry‐pressed to disks or bars. The green compacts began to sinter above 950°C. Relative density ≧ 99% and apparent porosity <1% were achieved when the specimens were sintered at 1500°C for 1 h in air. The linear thermal expansion coefficient and thermal conductivity of the CePO 4 ceramics were 9 × 10 −6 /°C to 11 × 10 −6 /°C (200° to 1300°C) and 1.81 W/(m · K) (500°C), respectively. Bending strength of the ceramics (average grain size 4 μm) was 174 ± 28 MPa (room temperature). The CePO 4 ceramics were cracked or decomposed by acidic or alkaline aqueous solutions at high temperatures.