Plastic mold tool steels

Technical data sheets for plastic mold tool steels


Plastic mold steels are a particular category of tool steels characterized by an excellent hardening penetration and resistance to wear and compression. The demand for wear resistance and compressive strength in plastic molds has increased considerably in recent years. The increase in use of plastic materials enriched with components and/or additives that improve their resistance, associated with the study of increasingly complex working parts in terms of shape and performance, have led to the study and design of new steels for plastic materials.



Among the most used steels we find type 2311, with excellent hardening penetration, suitable for sections up to 400 mm. Generally supplied in the quenched and tempered state, plastic mold steels are perfect for burnishing and photo-engraving. It can be nitrided up to about 800 HV, chromated or nickel plated. It is used for plastic molds with high finishing requirements. It is also used for low melting point light alloy molds, plates, mold holders.

The 2312 is a steel which is characterized by good hardening penetration. It is also supplied in the hardened and tempered state, which thanks to the presence of sulfur is particularly suitable for chip removal. This steel is mainly used for the construction of molds for plastic materials, even of large dimensions, provided

Product range


Quality IMSStandardUNIW.N°AISIProcessing routesSupply statusRounds (mm)Plates (thickness mm)Applications
W.2311(DIN-40 CrMnMo7)35CrMo8 – KU1.2311~P20PeeledQuenched and Tempered25-10220-600Suitable for molds up to approx. 400mm with excellent polishability and photo-engraving characteristics. It can be nitrided.
W.2311(DIN-40 CrMnMo7)35CrMo8 – KU1.2311~P20TurnedQuenched and tempered112-703  
W.2312DIN-17350 40CrMnMoS8-6 1.2312~P20PeeledQuenched and tempered25-10220-450Compared to grade 2311, it offers better workability; the uses are similar, but with lower polishability requirements.
W.2312DIN-17350 40CrMnMoS8-6 1.2312~P20TurnedQuenched and tempered263-703  
W.2738EN 4957 40CrMnNiMo8-6-4 1.2738~P20+NiRolled/Forged  300-1000Similar characteristics and uses to grade 2311, but with greater hardening penetration thanks to the presence of nickel.
W.2738EN 4957 40CrMnNiMo8-6-4 1.2738~P20+NiTurnedQuenched and tempered