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Yes! I am relieved. Thanks for all the help, and sorry for the confusing posts, I can get a little excited.
The only thing that makes sense to me is too much heat during heat treat.
John
P PugKnifeCompany
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Higher Tempering Temps needed after Cryo??
- Thread starter PugKnifeCompany
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The only thing that makes sense to me is too much heat during heat treat.
John
P PugKnifeCompany
BluntCut MetalWorks
Knifemaker / Craftsman / Service Provider
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- Apr 28, 2012
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- 3,476
I ht 440c for the first time this weekend. Along with a few other steels...
20180324: HRC at peak/AQ and 400F tempered:
A2 67, 64 https://www.alphaknifesupply.com/Pictures/Info/Steel/A2-TC.gif
Cruwear 67, 65 https://www.crucible.com/eselector/prodbyapp/tooldie/cruweart.html
RWL34 66, 65 http://www.damasteel.se/files/8414/5670/2913/flyer_rwl34_A4.pdf
Becut 63, 60.5 http://www.bestar-steel.com/wp-content/uploads/BECUT.pdf
440C 65, 63 https://www.alphaknifesupply.com/Pictures/Info/Steel/440C-TC.gif
W2 Chopper 67, 65
CruforgeV Chopper 66, 64 https://www.alphaknifesupply.com/Pictures/Info/Steel/CruForgeV-TC.gif
20180325: *not 400F temper yet - time to zzz
S110V 66
M2 67
M4 69
20180324: HRC at peak/AQ and 400F tempered:
A2 67, 64 https://www.alphaknifesupply.com/Pictures/Info/Steel/A2-TC.gif
Cruwear 67, 65 https://www.crucible.com/eselector/prodbyapp/tooldie/cruweart.html
RWL34 66, 65 http://www.damasteel.se/files/8414/5670/2913/flyer_rwl34_A4.pdf
Becut 63, 60.5 http://www.bestar-steel.com/wp-content/uploads/BECUT.pdf
440C 65, 63 https://www.alphaknifesupply.com/Pictures/Info/Steel/440C-TC.gif
W2 Chopper 67, 65
CruforgeV Chopper 66, 64 https://www.alphaknifesupply.com/Pictures/Info/Steel/CruForgeV-TC.gif
20180325: *not 400F temper yet - time to zzz
S110V 66
M2 67
M4 69
Don t get me wrong , but what's the point of your post in this topic ?
W
Wow you got an as-quench of 65 with 440C and 63 with 400F tempering? that is very strange for me... I'm very familiar with these steel and never ever heard it has as-quenched hardness over than 62... all of your number are absurdly high. are you sure your rockwell tester is accurate...
Wow you got an as-quench of 65 with 440C and 63 with 400F tempering? that is very strange for me... I'm very familiar with these steel and never ever heard it has as-quenched hardness over than 62... all of your number are absurdly high. are you sure your rockwell tester is accurate...
kuraki
Fimbulvetr Knifeworks
- Joined
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- 4,679
I think you've got it figured out but I just wanted to say yes, some steels react with lower hardness from aus temps that are too high. I struggled to get S7 60 RC out of the quench, even oil quenching it, from 1750F. Backing off to 1725 got me 61-62 as quenched.
BluntCut MetalWorks
Knifemaker / Craftsman / Service Provider
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- Apr 28, 2012
- Messages
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Point = Op's 440C 400F tempered HRC# is similar to my. So as his A2 
... so perhaps OP should go back and repeat original ht process to compare with his recent ht #s.
440C HRC fall in line with other stainless steels #s. I calibrated the tester whenever #s flux more than 1rc, also use opinel knife as 57rc blade/block. However the tester may be fine with calibrating blocks but not accurate on hrc above 61.9. Oh, I just remember: I could use the 3V chopper Nathan tested as a 65.5rc block (probably +- 1rc flux on a blade).
... so perhaps OP should go back and repeat original ht process to compare with his recent ht #s.440C HRC fall in line with other stainless steels #s. I calibrated the tester whenever #s flux more than 1rc, also use opinel knife as 57rc blade/block. However the tester may be fine with calibrating blocks but not accurate on hrc above 61.9. Oh, I just remember: I could use the 3V chopper Nathan tested as a 65.5rc block (probably +- 1rc flux on a blade).
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