How to refine the grain has been a difficult problem in the preparation of high-performance ceramic targets. In this work, the doping-induced grain refinement strategy was proposed, indium zinc oxide doped with different concentrations of Pr (Pr-doped IZO, PrIZO) targets were obtained by optimizing the sintering time and holding temperature. Effects of Pr doping content on the density, phase microevolution, grain size and resistivity during the densification process as well as the kinetics of the grain growth and the mechanism of grain refinement of PrIZO targets were investigated in detail. The results demonstrated that PrIZO targets with the atomic ratios of Pr:In:Zn=0.01-0.03:1:1 all exhibited the excellent performance with high densification (>99.10%) and mere average grain size (<3.0 μm) at low sintering temperature of 1350 °C. Additionally, XRD and EDS analysis indicated that PrIZO targets were composed of In2O3 and Zn3In2O6 with slight PrInO3, which formed by the limited solid solubility of Pr element. Combined with theoretical calculations, it inferred that the mechanism of grain refinement was attributed to the solute transformation and fine PrInO3 distributed at the grain boundaries of In2O3 phases, which produced the drag effect of grain boundary migration, then hindering the further growth of grains.
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