BS4659 BP20 Tool Steel

BS4659 BP20 tool steel stockholders and suppliers, delivering to the whole of the UK. BP20 is available as round bar, flat bar and plate. As an alloy tool steel BP20 offers good machinability even in the hardened and tempered (approx 300 HB) condition. This tool steels grade is suitable for case hardening or nitriding and is a popular plastic mould steel.

We welcome export enquiries for BS 4659 BP20tool steel. Please contact our sales office and consult our shipping policy for further details.

Related Specifications

ASTM A681 DIN 17350 BS EN ISO 4957

Alternative BS4659 tool steel grades we supply

BO1 | BD2 | BD3 | BO2 | BA2 | BS1 | BH13 | BP30| BM2 | BM35 | BM42

Form of Supply

BP20 tool steel is supplied in round bar, flat bar and plate. BP20 can be sawn to your required lengths as one offs or multiple cut pieces. BP20 ground tool steel bar can be supplied, providing a quality precision ground bar to tight tolerances.

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  • Plate
  • Flat
  • Diameter

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Heat slowly and uniformly to 1050°C. Do not forge BP20 below 930°C reheating if necessary. Cool very slowly after forging.

Carbon 0.28-0.40% Chromium 1.50-1.80%
Silicon 0.40-0.60% Molybdenum 0.35-0.55%
Manganese 0.65-0.95%

Heat uniformly to 770-790°C.  Soak well, cool slowly in the furnace.

When dies are heavily machined, we recommend stabilising just before finish machining in order to relieve machining strains. Heat to 460-500°C. Soak well and allow to cool in the air.

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

Heat uniformly to the required tempering temperature of between 100-600°C and soak for at least one hour per 25mm of section. Cool in still air.

BP20 steel may be nitrided to give a wear resistant case of approximately Rockwell C60 surface hardness with a case depth of 0.35mm to 0.5mm.

Case hardening of BP20 can achieve a surface hardness of between 55 to 59 Rockwell.

Heat treatment temperatures, including rate of heating, cooling and soaking times will vary due to factors such as the shape and size of each BP20 steel component. Other considerations during the heat treatment process include the type of furnace, quenching medium and work piece transfer facilities. Please consult your heat treatment provider for full guidance on heat treatment of tool steel.

BS4659 BP20 tool steel is supplied in accordance with our ISO 9001:2015 registration.