Zero thermal expansion in (1−x)PbTiO3–xBi(Mg,Ti)1/2O3 piezoceramics

Abstract

The compounds (1−x)PbTiO₃–xBi(Mg,Ti)_1/2O₃ (x = 0–0.7) were prepared in order to hunt for low thermal expansion piezoceramics, in particular for zero thermal expansion over a wide temperature range. The negative thermal expansion of PbTiO₃ was much weakened by forming a solid solution with Bi(Mg,Ti)_1/2O₃. Solutions of (1−x)PbTiO₃–xBi(Mg,Ti)_1/2O₃ with x = 0.2 and x = 0.4 exhibited zero thermal expansion covering a wide temperature range (from RT to about 500 °C). The (1−x)PbTiO₃–xBi(Mg,Ti)_1/2O₃ ceramics had high density and their mechanical performances were satisfactory with high fracture toughness. The promising applications of the zero thermal expansion materials (1−x)PbTiO₃–xBi(Mg,Ti)_1/2O₃ are due to its high piezoelectric d₃₃, controllable thermal expansion, and high thermal stability.