Effects of VC/Cr3C2 on WC grain morphologies and mechanical properties of WC-6wt.%Co cemented carbides

The effects of VC/Cr3C2 on WC grain morphologies and mechanical properties of WC-6wt. %Co cemented carbides were studied using scanning electron microscope (SEM) and mechanical properties tests. The results showed that the morphologies of WC grains in alloys doped VC were equilateral triangle with multi-steps in basal and prismatic planes because of the V segregate at (0 0 0 1) and slightly at (1 0 1¯ 0) surfaces of WC grains as (V, W) Cx carbide. However, the surfaces of triangle WC grains tended to become round without multi-steps as the VC grain inhibitor was partially replaced by Cr3C2. With the addition of VC, the hardness was improved due to the decrease of WC grain size and the transverse rupture strength decreased due to the multi-steps in WC grains. Additionally, the hardness and transverse rupture strength of the alloys had a little change with the partial substitution of VC by Cr3C2.