The susceptibility of wood-cutting tools to corrosive wear

The machining of green (wet) wood results in unique cutting tool problems. The non-homogeneous multicomponent nature of cutting tools and the water and water solubles in the wood result in electrochemical action. Both mechanical and corrosive tool wear mechanisms are thus active in such wood cutting. The relative magnitudes of mechanical and electrochemical effects were determined by analyzing tool life data in terms of simple models of the individual wear mechanisms. It was demonstrated that under conditions conducive to electrochemical action the major part of the total wear was due to corrosion. Some of the factors determining the corrosion susceptibility of cemented carbide tools were studied by measuring the electrical potentials developed between tool components in solutions typical of those found in various woods. The results of these tests indicate that electrochemical action can be influenced by changing the tool binder material, the relative percentage of the tool binder material in the tool and the carbide grain size.