Feb 11, 1999
How does ATS-55 (as used in the Spydies) compare to, say, ATS-34 (a la BM), or to the GIN-1/G-2 in the Spydies, or the AUS-#?

I have looked at all the steel charts I can find, and know the number comparisons. What I am looking for is opinions on how it actually works, holds an edge, resharpens, etc.

I'm no expert, believe me, but I think the correct "firing order" is as follows:
1: ATS 34
2: ATS 55
3: Gin1 (G2)
4: AUS 10
5: AUS 8
6: AUS 6

AUS 6,8,&10 are similar to 440 A,B,&C.
Sorry if this is confusing. -AR

P.S. I'll leave the details up to the real knife nuts!!! hehehe

[This message has been edited by Jackyl (edited 09 March 1999).]
I prefer ATS-55 over ATS-34 because it isn't as brittle as 34 is. Sharpness and edge retention are the same from what I have experienced. Cobalt is used in ATS-55 which makes it less brittle.

GIN 1 or G-2 is also a very high grade steel. I do prefer this over ATS-34 as well for the same reason, not as brittle, though it does loose edge retention just short of ATS-55 and ATS-34.

AUS-8 isn't brittle, gets a razor sharp edge, but, does dull faster than the these other 3 do. But on the good side, AUS-8 is much more rust resistance than these other 3 are.

My order of these listed above only,

GIN 1 or G-2,

There are some other steels which fall in btween these or above that I like better, but these are the order of just the ones brought up here on this thread that I prefer.


" Knife Collectors Are Sharp People

A little history for you.
ATS-34/154CM/BG42 are materials initially designed for bearings. The added Molybdenum gives these grades an ability to be tempered or heated to over 1000 degrees without losing hardness. 440C will soften at high temps which is why it is not used in bearing applications.

These other grades ATS 55, Gin 1, etc are all variations of high carbon 420 stainless. The
cobalt in the ATS 55, or in any grade for that matter, is intended to increase temper resistance and basically that is all it can do.
Aus 10, 8, and 6 are lessons in carbon content. The higher carbon content gives higher hardness and forms some carbide (thus better wear in AUS 10 vs 8 and 6)

When you boil it down, all these grades are simply trying to give you a stainless steel at a hardness acceptatable for holding an edge. The rest is just fluff.
Can't debate if what Ed says is fact or not, sounds up and up to me, though, but ATS-34 & ATS-55 are basically the same. Yes, he is right about what he says about Colbalt, that is why ATS-55 isn't as brittle as ATS-34 is.

The steels that I have used, I prefer the most to least are:

GIN 1 or G-2
420J or 420
and unknown stainless steels.

BG-42 might be at the top of the list, I have 2 Sebenza's but haven't used them ever. Bought just for my collection, but from what I have heard and read, BG-42 sounds like it holds an edge better than all of these, isn't brittle, and has very good rust resistance capabilities.

Again, these are the steels I prefer from my past experience.



[This message has been edited by Mark W Douglas (edited 09 March 1999).]
Thanks for the replies. Mark, it sounds like you REALLY dislike brittleness in any way, as you seem to rate ATS-34 well down the list, presumable mostly because of its brittleness?

Why does brittleness rate so strongly with you? I am not poking holes at your ratings; you did a great job of answering exactly what I asked. I am just interested in maybe how you use your knives, that would cause the brittleness to be so important. I am wondering how your uses might relate to my uses.

Thanks greatly for any info.



ATS-34 is okay in blades without points or actual tips. Tanto blades are okay with this steel because of the reinforced heavy duty so called tips they support. I as well as my late departed friend have busted the tips off of our knives more than once that have ATS-34 steel blades. Even chipping the edges has happen a numerous amount of times, too. Not being abusive, just hard work has done it. I have only had a problem with ATS-34 doing this, none of the others.

I like a blade steel like has very good edge holding abilities, no brittleness, and good rust resistance as well. ATS-34 only has good edge holding ability as far as I am concerned.

BM AFCK, busted tips and chips in blade, but my Micro Tech SOCOM M/A with the 154CM blade steel and basically the same blade shape and style, never had this type of damage to it. To tell you the truth, the SOCOM with the 154 CM has been worked harder than the AFCK ever has, and I might have even been a little abusive with the SOCOM as well. Still perfect blade.

An older Spyderco Police Model, had a titanium handle and ATS-34 blade, broke the tip and put a chip in the edge. Dropped knife and hit a hard wood floor, busted the tip. Stripped electrial wire, chipped the edge. I used my Lightweight Goddard with ATS-55 to strip wire until I am blue in the face, no chips there. I dropped it off of an 8' ladder and it landed on it's tip, no breakage there. Granted the tip isn't quite as pronounced as the BM AFCK is, but I would be willing to bet if it would have been made out of ATS-34, the blade would have broken for sure.

ATS-55, I have a few of these knives, the first being the Spyderco Goddard Lightweight, talk about using a knife hard! Most knives don't even get close to the hard work this one has seen. Again, blade is still perfect.

CPM-440V, a monster to sharpen, but it is long in between sharpenings, that's for sure! Blade, I feel practically impossible to damage. I rate this number 1 because it holds an edge very long, is not brittle at all, and has a high rust resistance to it.

Another late friend of mine had a Spyderco Miltary with ATS-34, two chips in the edge of his knife. I have the Spyderco Military with the CPM-440V, blade still looks new even though it has seen better days.

Yes, I hate brittleness. I like knives that work hard and can even take some abuse! There is nothing more disturbing to me than spending good money on a knife that breaks down under normal use. ATS-34 steel on blades with tips, I have no faith in it anymore.

Well, you asked ....



[This message has been edited by Mark W Douglas (edited 09 March 1999).]
Thats weird about your MicroTech and AFCK. It must be the heat treat. I thought 154CM was just an American version of ATS-34. Maybe I'm wrong.
I have to agree with you on the BG-42/154 CM comparison. Chemistry wise they are both similar to ATS-34 but when I looked at them metallurgically the ATS-34 was somewhat dirtier and there were some structures that didn't look too good.

440V is a whole different animal. It contains a fair amount of Vanadium carbide which is why it is much harder to sharpen. Vanadium carbide is about twice as hard as Chromium carbide which is what is contained in 440C, ATS34, 154CM, and D-2 tool steel.

420V has about double the vanadium carbide as 440V and is even harder to sharpen but the makers that use it say it performs better yet.

If any of you are going to be in Oregon for their knife show, I am going to do a presentation for them to discuss the metallurgy of knife steels.
Ed, I have heard about 420V being even more superior than the 440V. Haven't found a knife with my size and specs that I prefer yet with 420V. Wouldn't mind trying it, though! As far as the BG-42, well, like I said up above, haven't used my Sebenza's but I do believe it is the most superior of all stainless blades from what I know. Course, maybe there is even another Stainless steel blade I haven't heard of yet that is better!

Oh my, time flew right by me, I was supposed to be gone and heading back home 10 minutes ago. Oh well, always tomorrow

Thanks ED


154CM is the American ver. of ATS 34, accept I've read that ATS 34 is actually cleaner and has less pits in its structure. -AR
154CM has a few differences in percentages of the mixtures in the steel than ATS-34.

From this small percentage differences, 154CM becomes less brittle than ATS-34 from the heat treating.

Goes for the same with ATS-55 compared to ATS-34. ATS-55 also has Colbalt in it which makes it less brittle, too.

It has been my observations using a 20x beta magnifier to look at edges, that ATS-55 and 154CM has what appears to be a rougher surface to the edge than ATS 34. By that I think what I am looking at is carbide structure along the cantle. I just know when I look at my Axis the edge looks pretty smooth compared to my C16 and the Tempest I had. FWIW Oh yea the edge on the C16 seems to be pretty easy to bring back but seems to last longer than the AXIS. The Axis doesn't last as long and is harder to sharpen. It does get extremely sharp though.
hmmm.. an out of topic question, since we're talking about steels here...

Can anybody tell me something about the M2 steel used on the AFCK?


I just have to say that it's threads like this one that make this forum (and others) such a valuable resource. This one thread alone is overflowing with valuable, insightful, and practical knowlede that can't be found in any book or magazine.

Keep up the good work folks!!
Mark, I think that the reason why your microtech can take more is due to the thicker blade. Benchmade has a habit of making 0.12 inch thick blades, which are to thin in my opinion. Having said that, I do think that the batches of 154CM are of higher quality than a lot of the ATS-34 stock. But if properly treated they should be equal. As far as the rest of the list goes, I conseider 440C to be at the top of the impact resistance tough blade steel list and under the CPM steels, BG-42, ATS-34, 154CM as far as edge holding. In the corrosion resistance dept. I would say it's at the top along with 440V, and AUS-6,8,10 as well as 440A,B. ATS and 154 are low on the corrosion list.

In a folder I would go with 440V, BG-42, 154CM, 440C, ATS-34, ATS-55, AUS-10, 440A,B and AUS-8. AUS-8 does not seem to be able to hold an edge even as well as 440A in my experience.

In a fixed blade stainless, 440C, AUS-10, 440A,B, then the harder steels.

I like the ATS-55. I've been doing comparison testing between an Endura with the ATS and a Junglee Tri-Point with the AUS-10. I beleive both are improvements over AUS-8. The two steels seem to be equal in edge holding ability.They're both great knives but very different. When I asked the wife to compare her Delica with the Junglee Tri-point she took only about 10 minutes of playing and comparing before she handed me the Delica and said I'll keep the mini Tri-point thank you.

Different knive users have different criteria whereby they rate a steel type. For example, one may place more importance on brittleness, while another favors edge holding, corrosian resistance, or perhaps toughness. This is all understandable because knives are tools and we each have our own paricular tasks and ways of using them. However, what sorts of non-subjective tests exist to measure knife steel qualities. Aside from say, the RC scale, the practical meaning of which provokes lively debate, what's out there? Can brittleness, edge holding, corrosion resistance or ease of sharpening be quantitatively measured?