Annealing fubar
Annealing fubar
(OP)
We had a load of magnetic parts in our vacuum furnace run part way through the "burn out" cycle before the operator realized his mistake and shut it down. Then he ran the proper anneal cycle. These parts are either 8% or 12% chrome core alloys from Carpenter. Our normal anneal is 1450 F for 2-4 hours, they got up about 2000 F in the burnout cycle. The parts look OK and are meeting the hardness spec. I'm getting some critical dimensions measured.
Carpenter has this to say about heat treatment:
Due to its relatively low chromium content, Chrome Core (8)(12)-FM alloy will
form austenite if heated to too high a temperature, and some hardening
will occur if the austentized part is rapidly cooled. Consequently the best
heat treatment for improved soft magnetic properties is to subcritically
anneal.
So did the overheating do anything permanent that the subsequent anneal can't reverse?
Carpenter has this to say about heat treatment:
Due to its relatively low chromium content, Chrome Core (8)(12)-FM alloy will
form austenite if heated to too high a temperature, and some hardening
will occur if the austentized part is rapidly cooled. Consequently the best
heat treatment for improved soft magnetic properties is to subcritically
anneal.
So did the overheating do anything permanent that the subsequent anneal can't reverse?
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RE: Annealing fubar
They were cooled between the two treatments? They should have been.
If they weren't then re-run your standard sub-critial anneal.
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P.E. Metallurgy, Plymouth Tube
RE: Annealing fubar
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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.
RE: Annealing fubar
RE: Annealing fubar
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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.
RE: Annealing fubar
Could you test magnetic performance on parts/in the assemble? Let us know in case you messed up, I may have a solution for you.
RE: Annealing fubar
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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.