Microwave dielectric properties of Ca2P2O7

Microwave dielectric properties of α- and β-Ca2P2O7 ceramic materials were investigated, by a network analyzer at the frequency of 10 GHz. It was found that β-Ca2P2O7 could be sintered at 1150 °C for 2 h with high bulk density (98% TD) and α-Ca2P2O7 could be sintered at 1290 °C/4h with bulk density of 95.8% TD. The dielectric constant (εr) of β-Ca2P2O7 sintered at 1150 °C/2 h is 8.4, the temperature coefficient of resonant frequency (τf) is −53 ppm/°C, and the Q×f value is 53,500 GHz. α-Ca2P2O7 sintered at 1290 °C/4 h has εr of 7.8, τf of −97 ppm/°C and Q×f value of 14,115 GHz.