The aim of the study is to investigate the influence of Ru additions on the corrosionudbehaviour of WC-Co cemented carbides when exposed in corrosive media. The studyudinvolved the characterisation of the microstructures, morphologies and phases presentudby using the optical microscopy, SEM, XRD and Raman spectroscopy before and afterudcorrosion. The corrosion behaviour was investigated using the electrochemicaludpolarization tests in 1M hydrochloric acid, 1M sodium chloride and synthetic mineudwater solutions. Three types of corrosion tests were done on the samples byudelectrochemical techniques: potential versus time test, potentiodynamic polarisationudscans and chronoamperometry.udRuthenium affects c in 1M H2SO4 and synthetic mine water, but not really in NaCludsolution. It was also observed that the passivity range and corrosion resistance decreasesudin order of synthetic mine water> sodium chloride> sulphuric acid. It also appears thatudRu is more effective in improving corrosion resistance in all the solutions than a smalludvanadium carbide addition. Therefore, ruthenium additions of up to 3 wt% Ru of theudWC-10%Co alloy increased the corrosion resistance of the WC-Co alloys. This isudattributed to the stabilization of the cobalt fcc phase due to ruthenium additions whileudhcp phase is obtained when there is no ruthenium additions.
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