| This paper has launched a series of work to the repairing of the macroscopical crack of ceramic. Here so-called repair is that joining specific ceramic raw materials among the macroscopic crack, which were produced after sintering in ceramic products, then re-sintering in less than or the same with matrix sintering temperature, thus macroscopic crack is closed, and does not influence the basic function of use of the original ceramic products.On the basis of consulting documents and a large amount of practice, this experiment adopted the oxide (Al2O3 , ZrO2 ), the carbide (SiC) matches each other for the primitive material with the metal powder (Al powder ), adding proper quantity of sintered catalyst, have designed three prescriptions: (1)40%Al/Al2O3/6X%; (2)40%Al/(Al2O3/20ZrO2)6%; (3) 40%Al/(Al2O3/10ZrO2/10SiC)/6%X (the X is the sintered catalyst). In order to study expediently, using two kinds of ZrO2 and one Al2O3 as raw materials, signed as Z1, Z2 and A, a small crucible was prepared to imitate oxide ceramics macroscopic cracks. The filling component was sintered alone and the expansion rate was measured. The matrix and filling component were sintered together respectively, and the results were analyzed by XRD and SEM. The results showed that, the best effect is the A-1#.Samples of experiments sintered ordinarily in the air atmosphere, utilizing metal and carbide oxidize that can produce expansion effect, chemical reaction course will appear thus a large amount of liquid phase which leads to wet or reach the matrix combining through high-temperature plasticity with matrix. Based on A-1#, the best result was obtained after improving the experiment design under this condition. The consequence indicates that the repairing of oxide ceramics macroscopic cracks is feasible.
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