Three component piezoelectric ceramic - based on lead nickelate-niobate, titanate and zirconate modified with bismuth and zincate to increase piezoelectric constant

摘要

Piezoelectric ceramic consists of a solid soln. of 3 components of the formula Pb1-(3a/2)Bia(Ni1/3-bZnbNb2/3)xTiy ZrzO3 (in which x, y and z are the molar ratios of (Pb1-(3a/2)Bi)a(Ni1/3-bZnbNb2/3)O3 (I), Pb1-(3a/2)BiaTiO3 (II) and pb1-(3z-I)BiaZrO3 (III) and are within a region defined by the following points - A:x=65, y=30, z=5; B:x=60, y=25, z=15; C:x=30, y=37, z=33; D:x=30, y=40, z=39; and E:x=60, y=36, z=4. Also, a=0.005-0.05 and b is max. 1/6). The material has high piezoelectric constant and can be used for making electromechanical transducers. Replacement of pt. of the Pb in (I) by Bi improves the sintering properting and increases the piezoelectric constant. Replacement of pt. of the Ni in (I) by Zn has the same effects and also improves the Curie temp. and coercivity.