The use of carbide cutting tools in injection mold making is so commonplace that it is hard to imagine any other type of cutter being used. If all you had was high speed steel you would be very limited and things would happen at a very slow pace.
Carbide cutters, such as bull-nosed end mills, miniature end mills, ball end mills, indexable end mills, drills, reamers and all sorts of insert cutters fill any typical injection mold making operation.
Obtaining fine surface finishes and precise dimensions is always a challenge, carbide plays a critical role in this process. Because you can run at high speeds and feeds, it is possible to obtain nearly polish free surface finishes and very close tolerances.
With the newer high speed spindles in use, this becomes an even more important consideration: what type of cutting tool should I use? When you are cutting S-7 tool steel and the tolerances are +-.0002 inch, there is no doubt that carbide is the tool of choice! In fact, unless you are using diamond or CBN type materials, you simply will not be able to machine the hardened steel.
Randy Hough writes about
carbide cutting tools.