ZrC对TiC基金属陶瓷力学性能的影响

为研究ZrC对TiC基金属陶瓷性能的影响, 真空烧结制备了TiC-ZrC-10Co-10Ni-1C、TiC-ZrC-14Mo-20Ni-1C、TiC-ZrC-14Mo-15WC-20Ni-1C系金属陶瓷。采用三点弯曲法测试了材料的抗弯强度, 用单边切口梁法测试了材料的断裂韧性, 用洛氏硬度计测试了材料的硬度, 利用阿基米德原理测试了材料的相对密度。结果表明, 由于ZrC在金属相中的润湿性不理想, 导致材料的致密度不高, 因而, ZrC的加入并没有改善材料的抗弯强度和硬度。但ZrC对材料断裂韧性有明显的改善作用, 其主要机制为微裂纹增韧机制。

Effects of ZrC on the Mechanical Properties of TiC-based Cermets

Three series of cermets such as TiC-ZrC-10Co-10Ni-1C, TiC-ZrC-14Mo-20Ni-1C and TiC-ZrC-14Mo-15WC- 20Ni-1C were fabricated by vacuum sintering in order to study the effect of ZrC on the properties of TiC-based cermets. The transverse rupture strength of the materials was measured by three-point bending method, the fracture toughness, by single edge notched beam method, the hardness, by Rockwell hardness meter, and the relative density of each specimen, by Archimedes method. The results show that the relative density of materials is not good because the wettability of ZrC in metal phase is not good enough. Therefore, the transverse rupture strength and hardness decline with the addition of ZrC, however, ZrC improves the fracture toughness of the cermets by means of micro cracks toughening mechanism.