BS4659 BA2 Tool Steel

To forge BA2 tool steel, preheat at 650-680°C before raising the temperature to 1050-1100°C. Ensure the steel is fully and uniformly heated. Initial hammer blows should be light due to the comparatively high hot strength of BA2. The forging temperature must be maintained above 1000°C, the final forging should not be carried out below 900°C. To avoid the possibility of cracking, slow cool after forging.

As BA2 tool steel is supplied in the annealed condition re-annealing will only be necessary if the toolmaker has forged the steel, or if a hardened tool has to be re-machined or re-hardened. Heat the steel slowly to 850-870°C. After a minimum of two hours the furnace temperature should be lowered to 730-750°C, hold there for four to six hours. Allow to cool very slowly in the furnace to 600°C or below before removing the steel. Cool in air.

If the BA2 tool steel has been heavy machined or ground, it is advisable to stress relieve in order to minimise the danger of distortion or cracking during the subsequent heat treatment. Heat the steel slowly to 670-700°C, soak for a minimum of two hours per 25mm of section and allow to cool down in the furnace. The tools can then be finish machined.

Pre-heat the steel slowly to 790-820°C and soak at this temperature. Continue heating to the hardening temperature of 950-980°C. Allow sufficient time for the steel component to become heated through. Withdraw from the furnace and then air cool.

Temper with the least possible delay after hardening when the steel is hand warm. Heat slowly to the required tempering temperature between 150-550°C. and soak for one hour per 25mm of section. Cool in air. Double tempering is recommended.

Heat treatment temperatures for BA2, including rate of heating, cooling and soaking times will vary due to factors such as the shape and size of each 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 steels.

BS4659 BA2 tool steel is supplied in accordance with our ISO 9001:2015 registration.