Oil quenching air hardening steels.

jmforge

Well-Known Member
I have seen some folks like Roman Landis say that they oil quench air hardening steels. I am thinking about CPM 3V and maybe later some ALDO AEB-L equivalent. I have both AAA and 50 and I was wondering if you could quench it in 50 that had not been warmed up to perhaps make it a less violent clinch. do any of you have any experience with this? I would be going straight into dry ice after the quench and then tempering it 400 F. I have previously left these steels to the care of professional heat, treaters while I do my own regular high carbon stuff. The problem now is that either the price and the wait time have become unacceptable or, in a couple cases, these heaters are no longer taking small batches.
 
I’m watching this one. Per Alphaknife supply oil quench is acceptable for AEB-L.
 
The difficulty with the oil quench is the envelope. I did oil quench 440C and 154CM when I first started. I soon went to aluminum quench plates. Do you hold the package by the tang and cut the envelope away and then quench? Or dump the whole thing in the oil?
It can be a PITA trying to get those knives out of the bag, especially if it has stuck. Something like D2 or A2 you may be able to find coatings that tolerate the aus temp and that solves the bag problem. AEB-L and 3V need the bag for the most part. There's a guy on BF experimenting with coating AEB-L.
As far as your oils go, air hardening steels only need a "slow" oil. AAA is preferable over 50. BTW, 50 never needs to be heated unless it's cold. It's designed for room temp use, even for 1095 or W2.
A suggestion: if you own a hardness tester or have access, include an extra tab in the furnace run, wrapped separate. Take it and set it on the floor and let it cool. Then take it through the rest of your process with the blade. See how the hardness compares after dry ice.
 
I am wondering why one would use oil instead of an air or plate quench for these steels? Just curious, not judging.

Because the old HT instructions from the companies said "air or oil quench," for the most part, I would suspect. Followed by adhering to the worn concept that the faster the quench the better regardless the steel.
Oil quenching wrapped stainless blades became an instant thing of the past when I bought the plates. Always a mess. Plates are freakin' expensive now, though. That may send some folk in a different direction, too.
 
Because the old HT instructions from the companies said "air or oil quench," for the most part, I would suspect. Followed by adhering to the worn concept that the faster the quench the better regardless the steel.
Oil quenching wrapped stainless blades became an instant thing of the past when I bought the plates. Always a mess. Plates are freakin' expensive now, though. That may send some folk in a different direction, too.
They are expensive now. I purchased a pair on this site when I first started making knives way before I started using them. Glad I did.
 
The difficulty with the oil quench is the envelope. I did oil quench 440C and 154CM when I first started. I soon went to aluminum quench plates. Do you hold the package by the tang and cut the envelope away and then quench? Or dump the whole thing in the oil?
It can be a PITA trying to get those knives out of the bag, especially if it has stuck. Something like D2 or A2 you may be able to find coatings that tolerate the aus temp and that solves the bag problem. AEB-L and 3V need the bag for the most part. There's a guy on BF experimenting with coating AEB-L.
As far as your oils go, air hardening steels only need a "slow" oil. AAA is preferable over 50. BTW, 50 never needs to be heated unless it's cold. It's designed for room temp use, even for 1095 or W2.
A suggestion: if you own a hardness tester or have access, include an extra tab in the furnace run, wrapped separate. Take it and set it on the floor and let it cool. Then take it through the rest of your process with the blade. See how the hardness compares after dry ice.
I would not be putting these in an envelope. I would be using a 2000+ degree anti-scale goop. I use the high temperature, stainless foil for thermal cycling, stress, relief, and kneeling, etc. But not for he treating. I’ve used it on one occasion to wrap a mosaic Tile billet. The foil basically fell apart on the second welding heat, which was scary but convenient.
 
I would not be putting these in an envelope. I would be using a 2000+ degree anti-scale goop. I use the high temperature, stainless foil for thermal cycling, stress, relief, and kneeling, etc. But not for he treating. I’ve used it on one occasion to wrap a mosaic Tile billet. The foil basically fell apart on the second welding heat, which was scary but convenient.

I'd be interested in the name on that "2000+ degree anti-scale goop," if you're willing, please and thank you!

Edited to add: I see ATP 641 claims 2400F max. (Jantz) That might be interesting. I tried an ATP many years ago that was supposedly good to 2000F and it toasted the 440Cor ATS34 I was working with. Pitted like mad. Turns out the stuff is mostly borax, which gets REALLY acidic at those high temps. This stuff would be really interesting if it works, especially since it's paintable.

This thread on BF speaks about both ATP641 and NoScale2000 with AEBL.
 
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Because I have lots of oil and no giant aluminum plate nor a compressor to blow air.
Your logic makes sense but CPM 3V will fully harden in still air. No plates, oil, or blown air are needed. Again, no judgment, just trying to save you unnecessary steps. The good thing about working in your own shop is you can do it your way...
 
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