The complex evaluation of functional properties of nearly dense BCZT ceramics and their dependence on the grain size

In this article, the effect of dwell time (2–48 h) during isothermal sintering at 1520 °C on the grain size, density and crystal structure of (Ba 0.85 Ca 0.15 )(Zr 0.1 Ti 0.9 )O 3 is demonstrated. All ceramics exhibited the phase transition from orthorhombic to mixed orthorhombic and tetragonal phases between 12 and 24 h dwell time. The piezoelectric, dielectric and ferroelectric properties of these ceramics show a strong correlation with grain size in the range of 16.5–44.5 µm. Nearly dense microstructure (93.1–94.3% t.d.) was maintained during entire dwell time range without sacrificing much of its functional properties. Increasing grain size caused a little decrease in d 33 * piezoelectric constant from 480 pC/N to 460 pC/N while mechanical quality factor (Q m ) increased from 62 to 136. Diffusivity coefficient (γ) ranges between 1.46 and 1.55 which indicates a normal ferroelectric behavior.