不同粒度WC配比对粗晶硬质合金显微组织和性能的影响

Effect of WC Proportions with Different Particle Sizes on Microstructure and Propertiees of Coarsse Grain Cemented Carbide

分别采用单一WC粉球磨和采用两种粒度不同WC粉混合球磨的制备工艺制取3批相同配碳量、WC平均晶粒度相近的WC-6%Co粗晶硬质合金,通过分析合金WC晶粒的粒度分布,以及合金的矫顽磁力(H_(c))和断裂韧性(K_(IC)),研究不同制备工艺对合金WC晶粒的粒度分布、矫顽磁力、断裂韧性的影响。结果表明:不同制备工艺对合金的WC晶粒的粒度分布、钴相分散均匀性及断裂韧性有明显的影响。WC平均晶粒度相近时,采用两种WC粉末混合球磨工艺与采用一种WC粉末球磨工艺制取的合金相比,WC晶粒的粒径离差系数分别降低8.9%、15.6%,WC晶粒分布更均匀,合金矫顽磁力提高0.2、0.4 kA/m,合金韧性提升2.5%、10.8%。

Three batches of WC-6%Co coarse grained cemented carbides with the same carbon content and similar average WC grain size were prepared by ball milling of a single WC powder and ball milling of two WC powders with different particle sizes.By analyzing the particle size distribution of WC grains,as well as the coercive force(H_(C))and Fracture toughness(K_(IC))of the alloy,the effects of different preparation processes on the particle size distribution,coercive force and Fracture toughness of WC grains were studied.The results show that different preparation processes have obvious effects on the particle size distribution of WC grains,cobalt phase dispersion uniformity and Fracture toughness of the alloy.When the average grain size of WC is similar,compared with the alloy produced by using one WC powder ball milling process,the particle size dispersion coefficient of WC grains is reduced by 8.9%and 15.6%,respectively.The distribution of WC grains is more uniform,and the coercive force of the alloy is increased by 0.2 kA/m and 0.4 kA/m,while the toughness of the alloy is increased by 2.5%and 10.8%.