Low-temperature sintering of ZnAl2O4 ceramics with 4CuO-TiO2-2Nb2O5 composite oxide sintering aid

In this work, 4CuO-TiO2-2Nb2O5 (CTN) composite oxide was added to ZnAl2O4 as sintering aid. XRD analysis revealed that trace amount of new phases formed in the ceramic samples with CTN, which might promote the low temperature sintering of ZnAl2O4 ceramics. The sample with 2 wt% CTN addition sintered at 1125 °C can achieve the highest thermal conductivity of 8.6 W/m·K and the lowest microwave dielectric loss of 3.59 × 10−4. The sintering temperature and thermal conductivity of ZnAl2O4 ceramics decreased while the dielectric constant and loss increased with the increase of the CNT contents. ZnAl2O4 ceramics can be sintered at a low temperature of 950 °C with the CTN content increasing to 10 wt%, which make it a potential material for the low temperature co-fired ceramics (LTCC) application.