Preparation of PZT-based piezoceramics with transgranular fracture mode

摘要

In this paper, the effect of various doping and substitution elements on the mechanical fracture of perovskite-type (Pb_(0.95)Sr_(0.05))(Zr_(0.5)2Ti_(0.48))O_3-Pb(Mn_(1/3)Sb_(2/3))O_3-Pb(Mn_(1/3)Nb_(2/3))O_3 and (Pb_(0.95)Sr_(0.04))(Zr_(1-x)Ti_x)O_3-Pb(Mg_(1/3)Nb_(2/3))O_3 ceramics was investigated. The predominant transgranular fracture mode was observed in the modified piezoceramics mentioned above and the ZnO, SnO_2 and SiO_2 as trace additives were found beneficial to enhance the mechanical bonding force of grain boundaries. The mechanism of transgranular fracture mode was understood by the diffusion of doping elements into the structural lattice of perovskite-type oxides, agreed with the experimental results of reduced tetragonality, dielectric constant and piezoelectric coefficient.