BS4659 BO2 Tool Steel

BS4659 BO2 tool steel stockholders and suppliers, delivering to the whole of the U.K. West Yorkshire Steel are stockholders and suppliers of BO2 round bar. As an oil hardening grade BO2 tool steel is supplied in the annealed condition. It is characterised by offering good durability with excellent wear resistance and its ability to hold a good cutting edge. BO2 tool steel is a quality general purpose tool steel often used where the expense of high carbon high chromium tool steel grades would not be justified.

We welcome export enquiries for tool 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 | BA2 | BS1 | BH13 | BP20 | BP30| BM2 | BM35 | BM42

Form of Supply

West Yorkshire Steel are stockholders and suppliers of BO2 tool steel in round bar. Ground BO2 steel bar can be supplied, providing a high quality tool steel precision ground bar to close tolerances.

Contact our experienced sales team who will assist you with your BS 4659 BO2 tool steel enquiry.

  • Diameter

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Heat the BO2 uniformly to 1000°C. Forge within a range of 850-1050°C and re heat if necessary. Cool slowly to avoid setting up stresses.

Carbon 0.85-0.95% Vanadium 0.25% max
Manganese 1.50-1.80% Silicon 0.40%

Tool steel grade BO2 is supplied in the annealed and machinable condition. Re-annealing will only be necessary if the tool steel has been forged or hardened.  To anneal, heat uniformly to 760-780°C, equalise, then furnace cool (hardness about 229 Brinell).

Heat uniformly to 760-780°C until heated through. (If possible pre-heat at 300-500°C). Soak thoroughly allowing thirty minutes per 25 millimetre of ruling section and quench in oil.

Heat the BO2 uniformly and thoroughly at the selected tempering temperature between 150-300°C and hold for at least one hour per inch of total thickness.

Heat treatment temperatures for BO2 tool steel, including rate of heating, cooling and soaking times will vary due to factors such as the shape and size of each 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 BS 4659 tool steel grades.

BO2 tool steel is supplied in accordance with our ISO 9001:2015 registration.