AEB-L and S35VN comparison

[me2]

Here is my opinion on the 2 steels in question. AEB-L for kitchen knives, S35VN for hunting/skinning knives. High sharpness on food and processed meat vs high wear for dirty, yet soft, fur and tissue. Take care with bones.

As for the chart, remember that CPM has never claimed an overall increase in toughness, but does claim, and rightfully so, an increase in transverse toughness over ingot/rolled versions of the same steel. So doubling toughness is possible, as long as the samples are cut across the rolling direction and not parallel to it. Parallel toughness is the same. See Crucuble's comparissons of S30V to 440C in the S30V data sheets.

 

[Darrin Sanders]

I think when most people look at that chart they're not wondering whether the steel was cut longitudinally or transverse. If both grades of D2 are cut in the same direction there is NO way that the toughness would double just by using the PM process and that is what that chart implies.

 

[Willie71]

Here is my opinion on the 2 steels in question. AEB-L for kitchen knives, S35VN for hunting/skinning knives. High sharpness on food and processed meat vs high wear for dirty, yet soft, fur and tissue. Take care with bones.

As for the chart, remember that CPM has never claimed an overall increase in toughness, but does claim, and rightfully so, an increase in transverse toughness over ingot/rolled versions of the same steel. So doubling toughness is possible, as long as the samples are cut across the rolling direction and not parallel to it. Parallel toughness is the same. See Crucuble's comparissons of S30V to 440C in the S30V data sheets.

I have a couple guys using AEB-L for skinners, typically on deer. They love it. I find some guys want something really easy to sharpen, and they go with 15n20 or AEB-L, and some guys want to have better wear resistance, and they go for 52100, or S35VN. The guys wanting a pretty knife go with W2. :thumbup:

 

[james terrio]

Those charts are just close enough to reality to sort of imply a comparison and get you in the ballpark, but I trust 'em about as much as the ones claiming "old leaf springs are 5160" and so forth... which is actually not very much at all.

They look nice on a flyer or mouse pad (there's one from NSM on my desk right now ) but they're just not terribly useful. Each steel at what hardness? Which of several austenitizing temps, quench methods, etc for each alloy? C-notch or V-notch Charpy test? Cryo or not? Cryo before or after temper? You see the point... there are so many variables involved that it's just impossible to boil down 10 or 15 alloys to a chart the size of a business card.

 

[james terrio]

In any case I'll be having kitchen knives (as identical as possible in geometry) in AEB-L and S35VN HT'ed in the next few weeks, so I'll let you know what I find out. I'm pretty sure I have a good idea what I'll find - AEB-L is a lot easier to get really sharp, and S35VN holds it edge longer. That's just the way it generally works when comparing low-carbide-volume, very-fine-grain steels to high-carbide-volume ones. I'll be surprised if there's a huge noticeable difference in toughness between the two in normal kitchen use, but you never know. Abusive testing (chopping 2x4's and whatnot) may be a different story.

 

[me2]

I think when most people look at that chart they're not wondering whether the steel was cut longitudinally or transverse. If both grades of D2 are cut in the same direction there is NO way that the toughness would double just by using the PM process and that is what that chart implies.

Of course they're not thinking how was it cut. That's why its a marketing chart. In terms of whether or not it's accurate, bear in mind the transverse toughness for steels like D2 is very low. Crucible uses 440C, and presents a transverse toughness of 2.5 ft-lbs. A gain of only 1 ft-lb is nearly a 50% increase. Let's say D2 is only 5 ft-lbs in transverse toughness. S30V is 10 ft-lbs, according to Crucible's data. That's a 100% increase from D2, but it's still only 5 more ft-lbs. When people start throwing around percentage values, it pays to ask for the data if you can get it. One of the issues with impact testing is the scatter of the data. I've seen Charpy V-notch data vary from 115 ft-lbs to 200 ft-lbs and that was 3 samples from the same piece of steel.

 

[me2]

I have a couple guys using AEB-L for skinners, typically on deer. They love it. I find some guys want something really easy to sharpen, and they go with 15n20 or AEB-L, and some guys want to have better wear resistance, and they go for 52100, or S35VN. The guys wanting a pretty knife go with W2. :thumbup:

I'd take AEB-L for pretty much anything over S35VN. But S35VN has attributes that are advantageous in cutting softer abrasive material (dirty fur).

 

[Willie71]

I'd take AEB-L for pretty much anything over S35VN. But S35VN has attributes that are advantageous in cutting softer abrasive material (dirty fur).

I know a hunter who is testing 52100 vs S35VN for moose, which he reports has a lot of abrasive material in the fur. He swears by 15n20 for everything else, as it is quite tough, and super easy to touch up if he needs to in the field. :thumbup:

 

[Willie71]

In any case I'll be having kitchen knives (as identical as possible in geometry) in AEB-L and S35VN HT'ed in the next few weeks, so I'll let you know what I find out. I'm pretty sure I have a good idea what I'll find - AEB-L is a lot easier to get really sharp, and S35VN holds it edge longer. That's just the way it generally works when comparing low-carbide-volume, very-fine-grain steels to high-carbide-volume ones. I'll be surprised if there's a huge noticeable difference in toughness between the two in normal kitchen use, but you never know. Abusive testing (chopping 2x4's and whatnot) may be a different story.

I think you will find your predictions spot on. That has been my experience. I stopped using S35VN for kitchen knives, as the hair popping edges that kitchen knives are expected to have is much more attainable with AEB-L, or the fine grained carbon steels. No one complains about edge retention, even with lowly 15n20. S35VN might be a good choice for a boning knife or a cleaver though. :thumbup:

 

[samuraistuart]

Yeah...that prediction looks right from what I gather as well. A friend of mine called yesterday, wanting to make a kit knife, and was wondering my opinion on D2 vs O1 or 1095. He was concerned with being on a mountain, raining cats and dogs, and having to get thru an elk or two. My opinion on that is forget about D2, because my experience with it has only been with certain companies who use it.....and it is WAY freakin too hard in my opinion. Of course, that is all heat treat dependent....but it is usually way too hard, and you have to spend an eternity on the stones when it gets dull. He was concerned about corrosion, but I told him that in my opinion, it isn't an issue when you know what you're doing. I said that I would much rather have a fine grained carbon steel (or AEBL) that was easy to resharpen in the field with a small pocket stone, even if I had to stop once or twice to re-touch the edge. And that edge is always going to be razor sharp....because it takes literally seconds to bring it back if you stay on top of it. Maybe that is the case with D2 that is heat treated well.....I dunno. My experience with that stuff is just.....bad. Big thick, round shaped knives that are like trying to sharpen a hunk of glass.....no thank you. So that got me to thinking about the vaunted S35VN. Is it "easy" to re-touch up the edge like AEB-L or similiar. Just gonna have to play with it one of these days!

I'm with you guys on the 15n20. I wasn't expecting too much from that stuff. wrong again! Great edge retention and toughness at the higher numbers. Aldo even mentioned to me that he thought his was super low in Mn...and should make good hamons. Hmmmmm.

 

[james terrio]

...I would much rather have a fine grained carbon steel (or AEBL)...

The really interesting thing about AEB-L/13C26 is that it is essentially a fine-grained, "plain" carbon steel.

Let that sink in a minute... I know it sounds crazy (obviously it's stainless, JT, it has 13% chrome in it, duh)... but seriously, think about it. It's important to remember that chromium can serve at least three distinct purposes in steel alloys: reducing the severity of quench required, forming carbides, and adding corrosion resistance.

The whole reason it was developed with such moderate amounts of carbon (just under .7%) is so that dang near all the carbon is tied up with the iron, and allows it to get good and hard. Just like 1080 or 1070. There's simply not much left over to form other carbides.

So we get good hardness and a fine, tough structure that's easy to sharpen, and nearly all that chrome is "free" to act purely as a corrosion-resistor by self-passivating. Instead of some of the other "super" stainless steels that have twice or more the amount of carbon, a whole lot of which is tied up in carbides with chrome, moly, vanadium etc etc.

It's really the true "best of both worlds" between "carbon" and "stainless" steel. At least on paper...

 

[Willie71]

Stuart, the 15N20 is pretty bland below Rc60. It doesn't shine until Rc61/62. The nickel allows it to have edge stability that other carbon steels can't match at those Rc#'s, where they become chippy. It does develop a hamon to. I haven't had much success from the thinner 15N20, but the 1/8" stock is what this blade below was made from. The thinner stock is a different source, than the 0.130" stock.

[/url]100_2257 by Wjkrywko, on Flickr[/IMG]

 

[tim37a]

James,
I'd really like to see the results of your comparison between AEB-L and S35VN. I have been making all my prototype kitchen knives (chefs, slicers, utility ) out of S35VN. Most of my family have tried at least 1 knife and they love them. I took them to 1000 grit at 34* inclusive on an EdgePro and , if you are not careful, your finger is going to pay for it. They are home cooks who much prefer a knife which stays relatively sharp for 6 mos. with the occasional touch up on a ceramic stick to a knife which may be super sharp but has to have the edge touched up daily. None of them, except my brother, has the skill to keep an AEB-L knife super sharp. None of the women are interested in learning that skill, either. So, at least for now, I think I will continue using S35VN for kitchen knives for home use. Knives for professional chefs, however, may be better in AEB-L.
Tim

 

[Willie71]

James,
I'd really like to see the results of your comparison between AEB-L and S35VN. I have been making all my prototype kitchen knives (chefs, slicers, utility ) out of S35VN. Most of my family have tried at least 1 knife and they love them. I took them to 1000 grit at 34* inclusive on an EdgePro and , if you are not careful, your finger is going to pay for it. They are home cooks who much prefer a knife which stays relatively sharp for 6 mos. with the occasional touch up on a ceramic stick to a knife which may be super sharp but has to have the edge touched up daily. None of them, except my brother, has the skill to keep an AEB-L knife super sharp. None of the women are interested in learning that skill, either. So, at least for now, I think I will continue using S35VN for kitchen knives for home use. Knives for professional chefs, however, may be better in AEB-L.
Tim

At your sharpening there would be no advantage to a different steel. Keep doing what you are doing. :thumbup: I just delivered an AEB-L knife 0.007 behind the edge, 15deg inclusive, 8000grit plus strop. The weight of the knife will practically slice a tomato. I can't get S35VN to do that.

 

[samuraistuart]

15 degree inclusive? WOW. Now THAT is an edge. That is HALF of what Shun knives and the like are at. I don't think I've ever sharpened anything that low!!! Might have to give it a try. To be honest, I think pretty much all of my edges, kitchen and hunters, are right around 30 inclusive.

 

[samuraistuart]

Warren, did you get any of that thinner 15n20? I have a couple sticks and it came hard....around 42hrc IIRC. I have to anneal that stuff before I can work on it, which I don't mind doing. Mine was the .07" stuff.

 

[Willie71]

Warren, did you get any of that thinner 15n20? I have a couple sticks and it came hard....around 42hrc IIRC. I have to anneal that stuff before I can work on it, which I don't mind doing. Mine was the .07" stuff.

I had a thread a long time ago where Aldo described the different sources. The 0.048" is the same as the 0.130". The middle sizes are all the pre hardened stock, requiring annealing. The 0.07 stock makes great kitchen knives and skinners. :thumbup:

 

[Willie71]

15 degree inclusive? WOW. Now THAT is an edge. That is HALF of what Shun knives and the like are at. I don't think I've ever sharpened anything that low!!! Might have to give it a try. To be honest, I think pretty much all of my edges, kitchen and hunters, are right around 30 inclusive.

I do 20-25deg inclusive on most knives now. A few at 30, for the guys who are a harder on knives. Most guys i work with want slicers, rather than pry bars. 15 deg is pretty delicate, requiring a proper end grain cutting board. It'll slice your finger with basically no pressure. It requires maintenance though.

 

[tim37a]

EdgePro now recommends Japanese knives (except single bevel) at 17*, newer kitchen knives at 19*, and everything else at 21*. I'm not sure if those angles are each side or inclusive - will have to call them tomorrow and ask.

 

[Willie71]

EdgePro now recommends Japanese knives (except single bevel) at 17*, newer kitchen knives at 19*, and everything else at 21*. I'm not sure if those angles are each side or inclusive - will have to call them tomorrow and ask.

If you have a custom with optimized heat treat and one of the high end cutlery steels b(Rc65), you can go pretty fine. If you do, you need a good quality end grain cutting board with preferably 1.Rock Maple, 2. Black Walnut, or 3. Black Cherry as these are very forgiving on the steel. For general use, 25-30degrees inclusive works pretty well.