The Preparation Of ZrO₂/Al₂O₃ Composite Powder And Properties Of The Ceramic

Nanocrystalline ZrO₂/Al₂O₃ composite powders have been synthesized successfully from aqueous solution of metal nitrate and acetate containing citric acid as chelating agent by sol-gel method. The phase purity and morphology of the resultant powders have been analyzed by means of XRD and SEM, respectively. The two parameters original solution concentration and heat decomposition temperature were studied during the preparation. The ZrO₂/Al₂O₃ composite powders and the prepared ZrO₂ powders mixed with Al₂O₃ powders are made into ceramics through cold isostatic compaction and non-pressured sintering. The mechanical property ceramics of the ZrO₂/Al₂O₃ ceramics have been analyzed by means of Three Points Bending and SENB, and so on, and the microstructures were investigated by means of XRD and SEM. Then contrast the results. The relationship between the mechanical properties and microstructure was also analyzed.The nano ZrO₂/Al₂O₃ composite powders were made at the original solution concentration of 0.2 mol/L,0.4 mol/L,0.6 mol/L,0.8 mol/L and 1.0 mol/L respectively and then all sintered at 1300℃. The XRD and SEM analysis result indicate that the favorable uniform powders can be abtained at the original concentration of 0.6 mol/L, the average grain size is 34.25nm with high purity and full crystallization. The nano ZrO₂/Al₂O₃ composite powders were synthesized at the original solution of 0.6 mol/L and then sintered at the pressure of 1100℃,1200,1300℃,1400℃respectively . The XRD and SEM analysis results indicate that the favorable uniform powders with a high purity and an average grain size of 36.6nm can be abtained at 1200℃.Fine groups powder (the original solution concentration of 0.2 mol/L,...