Plastic moulding tool steels are used for the production of moulds for injection, compression, and extrusion of polymers. They are designed to provide good polishability, dimensional stability, wear resistance and I some cases also corrosion.

Hot work tool steels are intended for applications involving elevated temperatures and repeated thermal cycling. Key properties include hot strength, resistance to thermal fatigue and cracking, and toughness. Material performance is defined by controlled composition and microstructural stability.

Cold work tool steels are intended for applications involving high contact stresses and abrasive wear at lower operating temperatures. Key properties include high hardness, wear resistance, and resistance to chipping. Material performance depends on composition control and microstructural uniformity.