Effect of hydroxide precursor synthesis conditions on the properties of Gd₂Zr₂O₇ spark plasma sintered ceramics

The paper presents the first comparative study of the microstructure and mechanical properties of gadolinium zirconate ceramics produced by spark plasma sintering of powders obtained using hydroxide precursors synthesized with and without mechanical activation. The initial precursor was prepared via reverse coprecipitation of hydroxides. Mechanical activation of the precursor was performed in an AGO-2 planetary mill at a centrifugal acceleration of 20 g for 30 min. X-ray phase analysis revealed that the resulting ceramics were nanocrystalline. The ceramics produced from the mechanically activated precursor demonstrated superior mechanical properties, including higher microhardness and Young’s modulus, compared to those produced from the non-activated precursor.

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