Relationship between microstructural evolution and electric properties of B_2O_3-CaCu_3Ti_4O_(12) composite ceramics

摘要

Calcium copper titanate (CaCu_3Ti_4O_(12), CCTO) powder was mixed with boric oxide (B_2O_3) glassy phase up to 8% by weight to prepare the composite ceramics. The effects of B_2O_3 incorporation on the microstructures, electric and dielectric properties of CCTO ceramics have been systematically investigated. Adding B_2O_3 results in both the decrease of the CCTO grain size. These microstructural changes conjointly affect the dielectric constant. In addition, further B_2O_3 increase leads to its aggregation at grain boundaries. Meanwhile, the B_2O_3 addition reduces the nonlinear coefficient and influences the breakdown electric field.