Piezoelectric ceramic contg. lead titanate-zirconate - plus lithium and niobium or antimony, suitable for electric filters

摘要

The ceramic is based on a solid soln. of lead titanate and lead zirconate plus 0.1-2 wt. % MnO2, and has the general formula Pb(CU1/4B3/4)x(Li1/4B3/4)yTizZruO3; where B = Nb or Sb and x+y+z+u = 1. Pref. values are x = 0.01-0.34, y = 0.01-0.34, x+y = 0.02-0.35, esp. 0.06; z = 0.15-0.7; and u+z = 0.94. Numerous pref. values for x, y, z and u are stipulated, e.g. x = 0.09 used with y = 0.03 and z:u between 0.39:0.49 and 0.22:0.66. The ceramic is used esp. for devices employing acoustic surface waves, or for electric filters. It has better properties than conventional piezoelectric ceramics.