Effect of erodent particle impact energy on wear of cemented carbides

Cemented carbides match properties required for many wear related applications through the control of microstructure such as Co binder content, WC grain size, type and content of additives, etc. However, their hardness is usually raised at the expense of fracture toughness. The effect of hard erodent particle impact energy on the wear of cemented carbides containing differently sized grains (fine, medium, and coarse) and binder content (6, 8, 15 wt. %) was studied with the help of laboratory disintegrator and centrifugal erosion tester. The velocity of impingement was varied from 10 to 140 m s−1. Granite particles of grain size either of 3.0-5.6 or 0.8-1.0 mm were used as erodents. Influence of erodent particle energy (velocity) on the wear rate of cemented carbides is presented in detail. In general, the wear rate can successfully be described by power-law while some of the materials tested demonstrate slightly reduced acceleration in wear rate at the highest velocities studied, which might be explained by fracture of erodent and associated shielding effect. The observed formation of cracks filled with granite particles debris and Co binder after testing at the highest impact energies is similar to that found in materials experienced to rock drilling.