Modified lead titanate/zirconate solid soln piezoelectric c

摘要

Piezoelectric ceramic for electromechanical transformers, having improved electromagnetic coupling and dielectric constant, consist of quaternary solid soln. of a PbTiO3 + bPbZrO3 + cAO + dM2O5 (where A is bivalent Pb, ca, Sr, Ba or Cd; M is pentavalent Nb, Ta, Sb or Bi; O is oxygen; a, b, c and d are 30-60, 40-70, 1-30 and 1-15 mol.% respectively and a + b = 100%). Pref. a, b, c and d are 40-50, 50-60, 2.5-20 and 2.5-10 mol.%. - A ternary solid soln. system is prefd., consisting of a PbTiO3 + bPbZrO3 + AmMO2.5+ m (where m is 0.25, 0.5, 0.75, 1, 1.25 or 1.5 and a, b and c are 30-60 (30-50), 25-65 (40-60) or 1-30 (3-30) mole-% respectively). Opt. Ti and/or Zr are partly replaced by Sn.