Effect of ZnO submicron spheres addition on structure and properties of PZT ceramics prepared by spark plasma sintering

The uniform ZnO submicron spheres composed of nanodots were synthesized by solvothermal method and then added to PZT5A powder for spark plasma sintering. The effects of ZnO addition on phase composition， microstructure and electric properties of the lead zirconate titanate （PZT） ceramics were studied. The results indicate that PZT ceramics with a relative density higher than 97% can be prepared by spark plasma sintering at 900 ℃ for 5 min. The addition of ZnO submicron spheres is beneficial for speeding up the sintering process and promoting the grain growth of PZT ceramics. With the increase of ZnO addition， the content of the trigonal phase increases gradually. The addition of a proper amount of ZnO submicro spheres can improve the piezoelectric and dielectric property of PZT ceramics. When the mass fraction of ZnO is 0.10%， the superior overall performance of the material is optimal， at a frequency of 1 kHz， the piezoelectric constant d33=432 pC/N， the electromechanical coupling coefficient kp=0.56， the mechanical quality factor Qm=69.8， the relative dielectric constant εr=1360， and the dielectric loss tanδ=0.0227.