New lead zirconate-titanate based piezoelectric ceramic, especially for h.f. surface wave devices e.g. filters and oscillators, has a high niobium-to-manganese ratio and a fine sintered grain diameter

摘要

Piezoelectric ceramic is based on a lead zirconate-titanate having a high niobium-to-manganese ratio and has a fine sintered grain diameter. A novel piezoelectric ceramic has the composition Pbx((MnaNbb)yTizZr(1-y-x))O3, where x = 0.95 to 0.995, y = 0.055 to 0.10, z = 0.40 to 0.55, b/a = 2.01 to 2.40 and a + b = 1, and has an average sintered grain diameter of <= 2 microns . An Independent claim is also included for a surface wave device comprising the above piezoelectric ceramic.