HEAT TREATMENT
FORGING
Commence at 1000°C. Re-heat as necessary to avoid working below 900°C.
ANNEALING
Soak thoroughly at 840/850°C. Cool in furnace not faster than 20°C per hour.
STRESS RELIEVING
Heat uniformly to 650°C max. Allow to equalise and remove from furnace. Cool in still
air to room temperature.
HARDENING & TEMPERING
Thoroughly warm Tools or Components before charging
HEATING & SOAKING
(a) Salt Bath Procedure
Charge Tools into Pre-heater chamber at 300/400°C and soak thoroughly up to 1 hour
per inch of ruling section. Remove to Neutral Salt Bath operating at 700/750°C and
maintain at this temperature for 15 minutes per inch of ruling section. Raise heat of Salt
Bath to 950/970°C and allow sufficient time to eqaulise but do not soak for more than a
few minutes.
(b) Open Furnace Procedure
Charge Tools into muffle furnace working at 300/400°C and soak thoroughly, preferably
1 hour per inch of ruling section. Raise heat as rapidly as possible to 950/970°C and
allow sufficient time to eqaulise but do not soak for more than a few minutes.
QUENCHING
(1) Quench in oil - ALTERNATIVELY
(2) Quench in Martempering Salt Bath at 540°C. Allow to equalise and cool in still air.
Tools should be tempered immediately whilst still hand warm.
TEMPERING
Temper to your requirements according to the tempering graph - soaking at temperature
for 1 hour per inch ruling section or 2 hours whichever is longer. A second temper is
recommended as being beneficial. This steel should respod to hardening by the Vacuum
furnace, gas quench process. |