HEAT TREATMENT
FORGING
Commence at 1100oC. Re-heat as necessary to avoid working below 950oC
ANNEALING
Soak thoroughly at 860oC. Cool in furnace not faster than 20oC per
hour.
STRESS RELIEVING
Heat uniformly to 650oC max. Allow to equalise and remove from furnace. Cool in
still air to room
HARDENING & TEMPERING
Thoroughly warm Tools or Components before charging
HEATING & SOAKING
(a) Salt Bath Procedure
Charge Tools into Pre-heater chamber at 300/400oC and soak thoroughly up to
1 hour per inch of ruling section. Remove to Neutral Salt Bath operating at 700/750oC
and maintain at this temperature for at least Half an hour per inch of ruling section.
Raise heat of Salt Bath as rapidly as possible to 980/1000oC for oil hardening
or 1010/1030oC for air hardening.
(b) Open Furnace Procedure
Charge Tools into muffle furnace working at 300/400oC and soak thoroughly,
preferably 1 hour per inch of ruling section. Raise to 700/750oC and maintain
at this temperature for at least one hour per inch of ruling section. (This time may be
extended to 2 hours per inch of ruling section with beneficial results). Raise heat as
rapidly as possible to 980/1000oC for oil hardening or 1010/1030oC
for air hardening.
QUENCHING
(1) Quench in oil - ALTERNATIVELY
(2) Cool in still air - ALTERNATIVELY
(3) Quench in Salt Bath at 540oC. 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 respond to hardening by the Vacuum furnace, gas quench process. |
