ABSTRACT
The type of cutting tool influences the type of rock cutting mechanism, the energy required to excavate a unit volume of rock (specific energy), the resistance to wear and failure etc. Cutting tools can be distinguished on the basis of their shape or of the material they are made of. The differences between cutting tools may be reflected in their names. Materials used for rock cutting tools are mostly steel and tungsten carbide. The pick-points used for rock dredging are often made of steel, whereas the bits of rock cutting trenchers are made of steel with a tungsten carbide insert. The wear-behaviour of the different steel types or that of tungsten carbide is interesting. Since wear of steel seems to be more critical than of tungsten carbide in dredging, the study of the wear of steel is emphasized.
