抄録
The sol-gel method was applied to create Al2O3-Cr2O3 ceramics using aluminum ethylacetoacetate diisopropylate and chromium (III) chloride hexahydrate as starting materials. In the calcination at 600-1200°C it was found that the grains of Cr2O3-rich solid solution grew when they were exposed to the surrounding Al2O3-rich amorphous particles. The composition of the powders obtained by the sol-gel process changed with calcining temperature. Cr2O3-rich solid solutions firstly crystallize at low temperature and the composition of the crystallites changes as the crystals grow and react with the surrounding Al2O3-rich phases. The final sintered bodies fired under an Ar atmosphere showed higher relative densities as compared with those fired in air. A dense sintered body was not obtained when abnormal grains grew when calcining occurred.
