Temperature-stable dielectric properties from -20°C to 430°C in the system BaTiO3-Bi(Mg0.5Zr0.5)O3

Ceramics in the solid solution series (1-x)BaTiO3-Bi(Mg0.5Zr0.5)O3 are single-phase tetragonal for compositions x≤0.05, and cubic for x≥0.1. Plots of relative permittivity (er), versus temperature show double peaks for x=0.03 and x=0.05, changing to a single, frequency-dependent peak for compositions, x≥0.1. A progressive decline in ermax with increasing x leads to near temperature-stable dielectric properties over a wide temperature range. For x=0.3, er=570±15%, from -20°C to 430°C, and tanδ≤0.02 from 30°C to 420°C. For x=0.4, er=600±15% from 25°C to 420°C, and tanδ≤0.02 from 55°C to 280°C (at 1kHz). Values of dc resistivity were ~109Ωm at 250°C and ~106Ωm at 400°C. A piezoelectric strain of ~0.25% (at 40kV/cm) was recorded for composition x=0.03.