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View Full Version : High HRC Heat Treat for AEB-L?



HomeChef2000
09-20-2012, 07:06 PM
Hello All,

I have heard tell of people getting AEB-L to 63, but how they do it is another story. Does anyone have a program they are willing to share?

Thanks

John

Eamon Burke
09-21-2012, 03:07 AM
Why would you? It performs so freaking well at 59-60.

HomeChef2000
09-21-2012, 12:58 PM
Why would you? It performs so freaking well at ~60.

Because I prefer a harder blade.

K-Fed
09-21-2012, 01:28 PM
I'm no metallurgist nor hammer wielding smithy but from what I've learned every steel has a sweet spot in the hrc scale at which it performs best. Given that some of the best knife makers in the business keep the hardness ~60 I would expect that that's where it should be to get the best results out of the steel. :2cents:

HomeChef2000
09-21-2012, 01:34 PM
I'm no metallurgist nor hammer wielding smithy but from what I've learned every steel has a sweet spot in the hrc scale at which it performs best. Given that some of the best knife makers in the business keep the hardness ~60 I would expect that that's where it should be to get the best results out of the steel. :2cents:
Not for nothin', but Devin Thomas, a man who knows a thing or two about steel, takes his to 61-62. He keeps his methods, understandably, to himself, hence my posting here.

Eamon Burke
09-21-2012, 02:24 PM
The difference between 60 and 61 is pretty minor. The difference between 61 and 63 is not.

I would just consider a different steel. Not all steels do well at that hardness. It will get brittle.

HomeChef2000
09-21-2012, 02:36 PM
I could live with 62 - what approach would you recommend to get there?

If not, what stainless would you recommend to get to 63?

James
09-21-2012, 02:39 PM
For hrc 63, you should be looking into some pm steels. cowry x, zdp189, sg2 and srs-15 would all be pretty capable at 63, albeit probably pretty expensive

pkb
09-21-2012, 02:52 PM
I'm having Peters heat treat my AEB-L and their knife guy Brad--someone who knows his heat treats and his steels--has told me that 60 is the highest anyone should reasonably expect from AEB-L and he won't promise to get blades any harder than that on that steel. I think that casts some doubt towards those makers who are advertising 62-63 with the steel. Brad at Peters is using cryo, etc.. I got some back from him at 59-60 and they perform REALLY well and are a pleasure to work with.

DeepCSweede
09-21-2012, 03:05 PM
From what I have heard, Devin has been extremely helpful to some of the starting vendors on this site. You may want to send him a pm or an email. He might share his process with you if you ask. Never hurts to ask, worst thing he can do is say no.

HomeChef2000
09-21-2012, 03:10 PM
These respond to different posts - sorry for any confusion...

I wrote to Devin yesterday - he doesn't share his proprietary heat treat regime, understandably. That's why I am asking here.

Devin Thomas is a pretty credible guy - I can't imagine him lying about the hardness figures he is reaching. If you are not familiar with Devin, do some reading. For his mid-tech AEB-L knife he was originally going to farm out the heat treat but ended up not finding anyone capable enough for his standards, so he still does all his own heat treating.

I have an AEB-L (probably Sandvik 13C26, actually) that was heat treated at Peter's. I want a harder knife - it is a preference after using some very hard Japanese knives. I trust Devin's numbers are true, I am trying to find out how to get there. Does anyone know how?

pkb
09-21-2012, 03:26 PM
I'd forgotten that Devin had advertised those numbers and the conversation I had with Brad at Peters was fresh in my mind. If Devin says he's hitting 62-62.5, I'll believe him. Sorry if I offended anyone. I have a lot of respect for people who do the research and development that he's obviously done.

HomeChef2000
09-21-2012, 04:33 PM
The difference between 60 and 61 is pretty minor. The difference between 61 and 63 is not.

I would just consider a different steel. Not all steels do well at that hardness. It will get brittle.
I just found this quote from Larrin Thomas, Devin's son...

"(13c26) doesn't have a lot of carbon, but most of it goes into solution. I go for 63 Rc on my kitchen knives, and I would recommend to anyone to go for at least 62 Rc, and if you can get it harder than I can I would do it, because at 63 Rc it doesn't show any brittleness. "

Eamon Burke
09-21-2012, 04:39 PM
Never heard that before. Maybe try it. :dontknow:

HomeChef2000
09-21-2012, 05:03 PM
Never heard that before. Maybe try it. :dontknow:
I would like to try it - that's why I started the thread. I was hoping that someone might have insight into the heat treating algorithm to get the steel super hard.

WillC
09-21-2012, 05:33 PM
This steel is designed to be higher than 60 hrc. With correct heat treatment its not in the slightest bit brittle at 62 hrc, infact on a razor thin edge it will still roll a little when pushed to destruction rather than chip. This is due to the uber fine grain structure and a characteristic of the steel. It can be made made brittle or loose toughness by over soaking or under soaking at critical, its all in the standard data sheets. You will only reach 60 hrc without cryo, it hits 62/63 hrc with cryo. I cant see the point in using it less than 60 hrc personally, less than that you may as well use 12c which is a fine steel in its own right, gets a bit less hard but has more corrosion resistance than aeb-l.

SpikeC
09-21-2012, 06:04 PM
It is pretty simple, all you have to do is spend about 30 years experimenting with the metal and Bingo! you know how to do it! If it was easy to get the results that Devin gets then everyone would be doing it.

HomeChef2000
09-21-2012, 06:29 PM
It is pretty simple, all you have to do is spend about 30 years experimenting with the metal and Bingo! you know how to do it! If it was easy to get the results that Devin gets then everyone would be doing it.

I suppose a version of this could be the answer to every question where someone is asking for help. Seems a bit odd.

Andrew H
09-21-2012, 06:33 PM
Wow, no love for someone trying to do something even slightly different. Who knows, in a year or two we might all be saying anything under ~61HRc for AEB-L is terrible.

HomeChef, AKS has these instructions for getting ~62 (maybe a wee bit higher?) from AEB-L: http://www.alphaknifesupply.com/zdata-bladesteelS-AEBL.htm

It looks like you're going to have to cryo.

HomeChef2000
09-21-2012, 06:35 PM
Wow, no love for someone trying to do something even slightly different. Who knows, in a year or two we might all be saying anything under ~61HRc for AEB-L is terrible.

HomeChef, AKS has these instructions for getting ~62 (maybe a wee bit higher?) from AEB-L: http://www.alphaknifesupply.com/zdata-bladesteelS-AEBL.htm

You're going to have to cryo. That's all I know for sure.

Thanks so much, Andrew. Time to look for a dewar!

John

keithsaltydog
09-23-2012, 06:16 PM
I like AEB-L steel because it's small carbides make it easy to sharpen & edge holding is decent.My blade was HT at Peter's.Is not the high heat-cryo freezing-lower heat method an effective way to HT a blade?

Some feel that the Artiflex because it is machine finished is not up to par,from my experience because it is so easy to sharpen & takes a fine edge not unlike carbon it is one of the better all round stainless steels.Putting a polished convex edge on this thing is a piece of cake.60~62 is a good hardness for kitchen knives.M-390 may hold an edge longer,but it is harder to sharpen a tradeoff.