P20 (2311)

Grade Introduction:

P20 is an alloy tool steel which offers good machine ability even in the hardened and tempered (Brinell 300) condition. This steel gives an excellent polished finish and is one of the most widely accepted specifications for machine cut plastic molds and casting dies. P20 is often supplied in the hardened and tempered condition ready for machining. In this condition it gives excellent wear resistance but if maximum surface hardness is required for compression molding plastic dies or similar tools, the steel can be case hardened or nitride. For better machinability a higher Sulphur version P20S is available. For improved through hardenability in larger sections we also offer 1.2738 P20N

Grade Application:

P20 tool steel is ideally suited for the production of plastic molds. Typical applications include die holders, zinc die casting dies, backers, bolsters and injection molds. The versatility of P20 tool steel with its high tensile characteristics enables uses for a variety of other applications such as shafts, rails and wear strips.

Equivalent grades:

Country USA German GB/T
Standard ASTM A681 DIN EN ISO 4957 GB/T 1299
Grades P20 1.2311 3Cr2Mo

Chemical composition:

The following table shows the chemical composition of P-20 steel:

Element C Si Mn P S Cr Mo Cu
Content (%) 0.28-0.40 0.20-0.80 0.60-1.00 0.03 0.03 1.40-2.00 0.30-0.55 0.25

Hardness:

Max. 230

Heat treatment:

P20 tool steels are heated to 871-899°C (1600-1650°F) in the carburizing medium during the carburizing process. After being carburized, these steels are heated to 816-871°C (1500-1600°F) in order to be hardened and then held for 15 minutes and finally oil quenched.

Hardening:

Heat the steel uniformly to 820-840°C until heated through. Quench in oil.