Homogeneous templated grain growth of 0.65Pb(Mg1/3Nb2/3)O3-0.35PbTiO3 from nanocrystalline powders obtained by mechanochemical activation

The feasibility of a novel homogeneous templated grain growth approach for the processing of 0.65Pb(Mg1/3Nb2/3)O3-0.35PbTiO3 ceramics is studied. Novelty rests on the use of a nanocrystalline powder synthesized by mechanochemical activation for the matrix, and also for obtaining the templates via conventional sintering. Templates are (1 0 0) faceted cube-shaped microcrystals with an average size of 12 μm. The role of processing parameters such as the presence of PbO excess, and a hot-pressing step previous to the final thermal treatment is studied. Extensive growth of the templates and nearly full densification are demonstrated. The approach used here involves only conventional ceramic technology from a single source powder, and can be used as a means of obtaining larger crystals.