<P> The cutting surfaces of a milling cutter are generally made of a hard and temperature - resistant material , so that they wear slowly . A low cost cutter may have surfaces made of high speed steel . More expensive but slower - wearing materials include cemented carbide . Thin film coatings may be applied to decrease friction or further increase hardness . </P>
tools made from high-speed tool steel are generally used for what type of machining operations
milling