Because ceramic tool materials are sensitive to defects such as microcracks, this paper develops ceramic tool materials with crack healing function to solve this problem. In this paper, Al₂O₃/TiC/TiB₂ ceramic tool materials were prepared by vacuum hot pressing sintering technology. Cracks of different lengths are prefabricated on the surface of the material through Vickers hardness tester. The crack healing of the material was studied by high temperature air heat treatment. According to the recovery of material strength after heat treatment and the change of microstructure, the crack healing effect of the material was judged. The effects of different heat treatment temperature, heat treatment time and crack length on the healing behavior of ceramic materials were mainly studied. Research shows that the surface crack of the material is completely filled and healed by oxidation products. The flexural strength of the specimen with pre-cracked surface is only 24.50% of that of the smooth specimen. After heat treatment at 700 °C for 60 min, the strength of the cracked specimen returns to 91.35% of that of the smooth specimen. The maximum effective crack length for crack healing of this ceramic material is 500 μm. Through micro-morphology and elemental analysis, it is found that the main mechanism of surface crack healing is the filling and healing of cracks by liquid phase oxidation products of titanium diboride, namely boron trioxide and titanium dioxide, thus restoring the flexural strength of the material.

由于陶瓷工具材料对诸如微裂纹的缺陷敏感，因此，本文开发了具有裂纹修复功能的陶瓷工具材料来解决该问题。本文中，Al ₂ O ₃ / TiC / TiB ₂陶瓷工具材料是通过真空热压烧结技术制备的。通过维氏硬度计将不同长度的裂纹预制在材料表面。通过高温空气热处理研究了材料的裂纹愈合。根据热处理后材料强度的恢复和组织的变化，判断材料的裂纹愈合效果。主要研究了不同的热处理温度，热处理时间和裂纹长度对陶瓷材料愈合性能的影响。研究表明，材料的表面裂纹已被氧化产物完全填充并修复。预开裂表面的试样的抗弯强度仅为光滑试样的24.50％。在700°C下热处理60分钟后，破裂试样的强度恢复为光滑试样的91.35％。该陶瓷材料用于裂纹愈合的最大有效裂纹长度为500μm。通过微观形貌和元素分析，发现表面裂纹愈合的主要机理是二硼化钛的液相氧化产物即三氧化二硼和二氧化钛对裂纹的填充和愈合，从而恢复了材料的抗弯强度。 。