| Al2O3-ZrO2 composite powders precursors were prepared by compleximetry--precipitation method with Al(NO3)3·9H2O, ZrOCl2·8H2O, oxalic acid and ammonia as staring materials, and the preparation process of the precursors, preparation conditions and influencing factors are compared and analyzed.The microstructure, mineral composition, granularity distributing, average size of composite powders are characterized by TEM, DTA, XRDand laser grain size analyzer. The results indicate that: the concertration of composite salt was 0.50.7mol/l;precipitant droped with 2ml/min is optimal;compleximetry-precipitation method can over come that the several ions deposit homogenous diffcultly result from the difference of the solubility produced by co-precipitation method, and made the precursor sol more homogenous;the pH vale is about 9;ageing time is 12h;PEG about 5wt% was added in the precursor sol can propect sol and reduce agglomeration;the sol washed by alcohol can improve agglomeration obviously;It was found that composite powder was amorphous after heat treatment at 600 ℃ and zirconia crystaly appeared which was identified as monoclinic phase at 800 ℃, appeared obvious diffraction peak, but the intensity not strong and the peak is wide, it has little α-Al2O3 crystaly appeared;after heat treatment at 1100℃, the volume fraction of ZrO2 tetragonal phase increased, appeared edged diffraction peak and the intensity strong, the peak is narrow, the volume fraction of α-Al2O3 crystaly increased;the average size of composite powder is 3.704μm by using compleximetry-precipitation method and 7.052μm of co-precipitation method.
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