| 摘要 |
PURPOSE:To improve a piezoelectric constant by setting the content of Pb which is an A site component in PbTiO3, PbZnO3, Pb(Sn1/3Nb2alpha/3Sb2(1-alpha)/3)O3 system slightly lower than the stoichiometric compsn. in comparison with the content ratios of Zr, Ti, Sn, Sb and Nb which are B site components. CONSTITUTION:Raw materials Pb3O4, ZrO2, TiO2, SnO2, Nb2O5 and Sb2O3 are weighed and are mixed by a wet process using zirconia balls, etc., in such a manner as to satisfy x+y+z=1, 0.47<=x<=0.52, 0.43<=y<=0.48, 0.02<=z<=0.08, 0.20<=alpha<=0.60, 0.98<=beta<1.00 when the compsn. formula of the piezoelectric porcelain compsn. to be formed is expressed by formula shown. The mixture is then calcined in an oxidative atmosphere kept at 800 to 1000 deg.C after drying. The calcined powder is pulverized and is molded by a known molding method such as press forming, and thereafter, the molding is sintered at 1150 to 1250 deg.C in the oxidative atmosphere. The resulted porcelain is further heat-treated in an inert gas contg. oxygen under 500 to 200atm by a hot hydrostatic sintering method. |
