Cemented tungsten carbide die has b

Cemented tungsten carbide die has been used in wire drawing for almost a century. A combination of strength and wear resistance hasmade this material widely accepted in the steel wire industry, particularly in drawing steel cord filament. Used cemented tungsten carbidedies, collected from different sources where different lubricants were applied in the wet drawing process, were dissected with high speeddiamond saw and examined by using scanning electron microscopy. Failure modes of cemented tungsten carbide dies were classified.Electrochemical properties of pure cobalt wire and cemented tungsten carbide were examined by anodic and cyclic polarization measurementsto investigate the corrosion resistance of cobalt and cemented tungsten carbide in wire drawing lubricants.Results show that binding agent (cobalt) in cemented tungsten carbide might be selectively leached in certain lubricants, and the leachingrate increased as oxygen concentration decreased in the lubricants and pH was lowered inside the crevice. Contact of steel wire on thecemented carbide die due to the mismatch of slip during drawing could be the original source of stress. Synergic effect of stress and leachingcould be the answer for the severe cracking of cemented carbide dies in the wet drawing process