Cemented carbide is often used as one of the cutting tool materials. During cutting, with a rise in temperature, serious diffusion wear of cemented carbide cutting tools will occur. In this paper, the influence of triethanolamine-containing cutting fluid on the diffusion wear of cutting tools was studied. The simulation experiments of cemented carbide rubbed against steel was adopted The contents of metal elements on the surfaces were analyzed by SEM and the cutting fluids containing Co were determined by spectrophotometry. The results showed that the dry cutting cemented carbide is accompanied with diffusion of W, Co, Ti, Fe, etc., and the triethanolamine-containing cutting fluid can evidently reduce diffusion ratio of W, Ti, and Fe on surfaces after rubbing, but the diffusion ratio of Co can not be reduced. The reason is that triethanolamine in cutting fluid can accelerate diffusion of Co from cemented carbide. Therefore, triethanolamine-containing cutting fluids should be avoided in cutting with cemented carbide cutting tools.
