Enhanced temperature stability in 〈111〉 textured tetragonal Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃ piezoelectric ceramics

Two different templates (〈001〉 Ba₆Ti₁₇O₄₀ and 〈111〉 BaTiO₃) were used for synthesizing 〈111〉 textured tetragonal 0.6Pb(Mg_1/3Nb_2/3)O₃-0.4PbTiO₃(PMN-40PT) ceramics. It was found that a texture degree of 95% along 〈111〉 direction can be achieved by using only 1vol.% 〈111〉 BaTiO₃ template due to its high chemical stability in the PMN-40PT matrix. The textured PMN-40PT ceramics with tetragonal structure exhibited an excellent temperature stability of piezoelectric properties due to the absence of intermediate phase transitions between room temperature and the Curie temperature. Unlike the single crystal counterpart, the effect of 〈111〉 grain orientation in the textured PMN-40PT ceramic on enhancing the macroscopic piezoelectric response was not significant in spite of its giant local piezoresponse. We provide detailed discussions on the nature of piezoelectric response in the 〈111〉 textured tetragonal PMN-40PT ceramic with "3T" engineered domain configuration and resultant strategy to realize high performance piezoelectric ceramics.