A wide variety of materials have been developed to perform as tools. However, tool steels
are still the most used tool materials. Both the traditional grades, developed empirically, and new grades are being upgraded by special processing or by the use of new metallurgical concepts, e.g. microalloying, to optimize properties. Niobium, a strong carbide-forming element, is a newcomer to this field which is progressively finding its way into a variety of tool steels.