1084 vs. 1095 vs. O1

Vs 52100

David Weaver

...I already made a 52100 iron and it's definitely sweeter than 1095. A little bit more expensive, but not too much. It works like 1095 when cutting and filing and grinding annealed, but definitely better toughness and less tempering needed to get acceptable toughness.

Time will tell if It's more likable than O1 (And maybe a durability test), but it's very sweet as far as steels go (sweetness of the edge) and the microscope shows its wear to be super even, much like the ward iron.

It warps like 1095, though - I wouldn't expect to see it any time soon from boutique makers. I don't really care about the warp, it's another 15 minutes or so of work and sometimes not that much.

Even the very first edge that was ground by a 60 grit belt grinder contact wheel and then just honed had that sweetness and nothing dropped out of the edge. It should only get better after I get away from the original sized and ground edge.

Re: aeb-l

David Weaver

Aeb-l is a high toughness stainless with lower abrasion resistance and very small grain. In knife tests, it outlasts carbon steel only by a little and in terms of making irons, it saws and files like carbon steel.

aeb-l and 1095 out

David Weaver

1095 makes a decent iron, but it's not tough at high hardness or even moderate hardness.

Aeb-l should be tough but I need to give the heat treat another shot. It has a small window where it will be hard enough without being brittle. It's a stainless with tiny grain size and good toughness at hardness around 61 if done right.

1084 is very stable and not chippy at all, but not quite the same edge smoothness as 52100 or high hardness o1. Running a test to dullness in maple and will report what I find, but 52100 is smooth so far...very, and should last similar to a2. Very easy sharpening, even at higher hardness.

Test complete...will post results later...

David Weaver

First is aeb-l needs normalization to achieve high hardness and good toughness (we can't do it - has to soak at 1950f or so), and I'm not sure even then it will attain a good combination of strength and toughness. Commercial heat treat is a no go for me. Too expensive.

Ideal 52100 and o1 wear identically, but 52100 is even easier to sharpen on india/novaculite combo at high hardness.

1084 is about 80% as long wearing as the two above, but surprisingly good and tough at high hardness. Very easy to sharpen.

1095 lacks toughness at high hardness and doesn't wear well. Chips in against the grain planing.

What is the goal here

Bill Tindall, E.Tn.

It comes as no surprise that 1095 is a poor tool steel. It comes as no surprise that steel alloyed to achieve toughness, well, achieves toughness.

If you are trying to replicate something from 1870 you are doomed without some sophisticated analytical gear. Steel from this or that region was superior for this or that application likely because of naturally occurring alloy elements that made it so. If one wants to replicate a cast steel from some past time, you need to begin with a detailed analysis of that steel. One might discover it looks like O-1 or whatever.

I recall historically bridge suspension cable was made from iron from some particular mine. The only reason a particular mine would make a superior steel is if this mine had minor constituents that gave the iron some desirable properties.

As the means to analyze minor alloying elements became possible

it would have been logical that superior steel from some region was analyzed to see what made it superior. This knowledge at first was the inspiration to make synthetic versions and learn cause and effect of alloying constituents.

Have to hear from David, but

Wiley Horne

I am under the impression he is searching for,

1. The most durable chisel steel, which satisfies the following constraints:

A. Will withstand chopping at RC62 or higher

B. Hones on novaculite without difficulty

C. Dulls by gradual wear; no microchipping under scope.

D. Is amenable to home brew heat treating.

In other words, a steel easily sharpenable, will take high hardness, and further does not spall off carbides, but rather dulls by gradual and even wear. And he can heat treat it at home.

I’m interested! My impression is that at this point, it’s between 52100 and whatever file steel is.

Wiley

This is for planing...

David Weaver

..at this point, though 52100 may have potential for chisels, but so does O1.

What I don't like about XHP/V11 is that it lacks toughness but grinds half as fast as anything else. I want to go through a couple of carbon steels and see how they wear. I'm not looking for something that wears exceptionally long, just something that the regular honing process stays ahead of the nicks just with abrasion.

Good O1 does this. I kind of wondered if there's anything else like it that's a little bit more plain, but also got 52100 just because someone suggested "why aren't plane irons made from it?". Well, I"ll find out. I got the 1084 and 1095 a long time ago just looking to make plain irons.

52100 and O1 look from the test like the winners, but 1084 has some merit (not longevity, but excellent toughness and it's certainly smooth sharpening and doesn't need to be low hardness to be that).

AEB-L is a wildcard. It has absolutely tiny carbides in it, and slight changes in chemistry ruin that. It also has the potential to have decent toughness at 62 hardness or so and approach 3V wear/edge life while sharpening like 01. I think to really get top levels of hardness out of it, commercial treatment is necessary, but I'll keep trying. I gave the hardening and tempering on my AEB-L iron a second go, and it's easier to sharpen than any of the other irons (hardness is slightly less) with better edge life. (It's stainless - it gets thrown into this test of carbon steels only because its carbides are extremely tiny, and it sharpens like carbon steel. Why it doesn't have more resistance on stones, I don't know).

XHP is very simple to get a good quench and temper from, but that may be because it's PM. AEB-L is a bit more picky (but it does actually have higher potential hardness than V11, and if the hardness is backed off, far better toughness. Combine that with the fact that it abrades easily on stones and there won't be any extra screwing around to remove nicks).

(files have my heart with chisels. Chisels aren't about toughness, they're more about strength. If you're going to really go after chisels for an experienced user, it's acceptable toughness but high strength. 1095 probably makes a better chisel than it would a plane iron because of that).

AEB-L Composition and notes—zknives

Wiley Horne

http://www.zknives.com/knives/steels/aeb-l.shtml

See also Hitachi PS-60—they appear identical.

Re: AEB-L Composition and notes—zknives

David Weaver

Very similar - AEB-L, 13c26, (i'm sure there's a DIN number), PS-6 all appear to be the same or about the same.

I don't know much about steel, but I do know that when it comes to some of these, there can be very minor variances in alloy from one maker to the next.

I think Larrin Thomas's page says bohler was the original maker of the stuff.

It's starting to get some appeal among knife buyers who want something that can be sharpened like carbon steel with stones that sharpen carbon steel, and without odd carbide behavior. It's kind of a "nothing else quite like it" alloying mix that allows the carbides to be so tiny so as to look like a carbon steel, and then its behavior is like that other than the rust resistance and the need for more experimentation (on my part) to be able to get acceptable results in open atmosphere. I already have acceptable results, but want to be able to drive the hardness up a bit further as softness comes with easily raising a wire edge when you may not want to.

What is strength?

Bill Tindall, E.Tn.

How is it measured and what are its units, metric or English?

compressive, tensile, yield..

David Weaver

compressive, yield, tensile, whatever. Generally improved with hardness. More important in the sense of making and using a chisel than reading documents about bridge parts.

Chisels that have the sweetest feel/clean cutting are on the high end of hardness, and most of the high toughness steels (if toughness is chased) don't have the strength at the edge to not deform in the first place. They just tolerate the deformation.

You can see the results of chisel tests coming before they're run - whatever steel has reasonable toughness at high hardness wins. If there are a couple of samples overhard, then those don't work as well because the edge chips (even in sharpening, it can chip, and the chisels never take a really crisp edge because of it).

If you have, say, a chisel at 60 hardness that's super tough, and one that's 64 hardness and tough enough, the latter will win the contest, will feel sharper off of the same stone (unless you go to very small abrasives, but even off of a buffer, the harder chisel will have a more crisp edge and keep the crisp last part of the edge better). The harder steel generally has higher strength, and lower toughness in same alloy.