Are processing conditions similar in ball milling and high-pressure torsion? The case of the tetragonal-to-monoclinic phase transition in ZrO2 powders

Y2O3 partially stabilized zirconium oxide powders have been mechanically processed by ball milling. A tetragonal-to-monoclinic phase transition occurred, accompanied by a refinement of the microstructure, and an increase in the dislocation density. The final phase composition, average size of coherent diffraction domains and dislocation density are comparable to those obtained after high-pressure torsion. This suggests that powder particles experience similar mechanical deformation conditions when involved in a collision or submitted to high-pressure torsion.