Through the analysis of the fracture process of the single-crystal indentation edge of alumina ceramics, the law and mechanism of fracture damage of the ceramic edge are found, so that in the future application process, the alumina ceramics can be better controlled, thus Reduce the possibility of edge cracking.

It can be found from the test analysis that the edge fragmentation of alumina ceramics is composed of a series of discontinuous catastrophe processes, and its damage evolution process has undergone an incessant transition between stability and instability in turn, with significant catastrophe characteristics. In this regard, the gray-point mutation theory model based on cumulative count and cumulative energy can be used to better describe the mutation state of the damage evolution process.

In the stable stage of alumina ceramic edge fragmentation, the propagation speed and strength of micro-cracks in the material are relatively smooth, the change of count rate and energy release rate is relatively stable, and the bifurcation set equation is greater than 0; while in the sudden stage of edge fragmentation, The speed and strength of micro-cracks inside the ceramic material increase dramatically. Both the count rate and the energy release rate will show large peaks, and at the moment when the edge is broken, the count rate and the energy release rate reach their maximum values.

With the continuous increase of the applied load of alumina ceramics, there will also be small mutations inside the ceramic material, but before the critical load, because these mutations are not strong, they will not have a macroscopic effect on the performance of the material.

When the applied load reaches a certain critical load, the edge of the alumina ceramic will instantaneously crack, which shows that the entire damage process of the alumina ceramic has significant abrupt changes. Predicting the damage evolution process of alumina ceramic edge cracking like this can provide a theoretical basis for formulating relevant preventive measures.