Selective Electrolytic Corrosion Behaviours of WC in WC-Co Cemented Carbide

In this work, WC grains in WC-Co cemented carbide were selectively electrolytic corroded and the effects of corrosion time, WC mean grain size and Co content on corrosion rate were systematically investigated. The results showed that corrosion rate decreased with the prolonging of electrolytic corrosion time. The WC-9Co cemented carbides had grain size of 2.9 μm The intensity of Co diffraction peaks was found to exceed the WC diffraction peaks when corroded for 4 hours, and the WC diffraction peaks disappeared when corroded for 8 hours. The corrosion rate increased with the decrease of WC mean grain size and the Co content. As the WC content increased in cemented carbide, it was necessary to increase corrosion time when analyzed Co phase in the cemented carbide by X-ray diffraction.