ZrO2添加量对等离子放电烧结制备WC-6Co组织和性能的影响

以WC-6Co为主体原料，通过添加不同含量的ZrO₂作为烧结助剂，采用SPS烧结技术制备出性能出众的WC-6Co硬质合金，研究了ZrO₂烧结助剂对硬质合金显微组织及力学性能的影响规律.结果表明:随着ZrO₂添加量的增加，试样的显微组织更加致密，相对密度更大，硬度和断裂韧性也有一定程度的增加.并且，当添加ZrO₂的质量分数为3%时，试样的相对密度达到96.7%，维氏硬度增加到20.28kN·mm^-2，断裂韧性增长到12.7MPa·mm^1/2，综合性能最优.研究发现，ZrO₂可以通过促进离子的扩散和颗粒的重排促进烧结，最终使得材料的相对密度和性能均得到提升.

Effects of ZrO2 Addition Amount on Microstructure and Mechanical Property of WC-6Co Prepared by Spark Plasma Sintering

A series of WC-6Co cemented carbides with different amount of ZrO₂ addition were quickly prepared by spark plasma sintering (SPS) and the effects of ZrO₂ addition on the microstructure and mechanical properties of the alloys were investigated. The results show that with the increasing ZrO₂ additive amount， the microstructure of the sample becomes more condensed， the relative density is greater and the hardness and fracture toughness also increase. When the mass fraction of ZrO₂ addition is 3%， the performance of the tested sample is the best one， in which the relative density is 96.7%， the Vickers hardness is 20.28kN·mm^-2 and the fracture toughness is 12.7MPa·mm^1/2. It is found that the ZrO₂ can enhance the sintering by promoting the ion diffusion and the particle rearrangement， leading to the improvement of the relative density and mechanical property of the cemented carbides.