Stress Relaxation in PZT

Time‐dependent deformation in the sonar transducer ceramic, PZT, was studied by stress‐relaxation techniques. Logarithmic stress relaxation was not observed but the data could be treated in terms of an analysis of thermally activated deformation by Reed‐Hill and Dahlberg. The room‐temperature activation energy and activation volume of the rate‐controlling deformation mechanism were measured as 25 kcal/mol and 7000 Å 3 , respectively. A dislocation model of the domain processes responsible for deformation, consistent with the experimental data, is presented.