Besides carbon, which provides the alloy’s hardness, the essential alloy-elements of the tool-steels are silicon, manganese, chromium, molybdenum, vanadium, tungsten and cobalt.

For the fine adjustment of the steel during the melting, they are readily available to the steel worker in highly enriched forms as ferrous alloys. They are alloyed with the steels in well-defined quantities in order to control qualities like the hardenability, wear-resistance, toughness, corrosion resistance, heat resistance and load durability.

In the area of heat-resistant cast products, the alloy-content is essentially an interplay of chromium and nickel to influence temperature-durability, thermo shock resistance and durability against different furnace-atmospheres with sufficient mechanical load capacity.