ATS-34 steel not as good

4

424v8

Joined
Dec 12, 2002
Messages
18
Is the ATS-34 steel less superior than the 154CM steel. Lately, I have noticed that many knife manufacturer are using less and less of the ATS-34 steel in the production line particuarlly Benchmade. Is it because cost factor??
 
From what I understand, 154CM and ATS-34 are chemically identical. The difference is that CM is domestic and ATS is from Japan. I think U.S. firms are using 154CM because it is from the States.
 
I can't really confirm that they are identical, but they look similar and exhibit similar properties. They very well could be identical.
 
Originally posted by Steven Roos
I can't really confirm that they are identical, but they look similar and exhibit similar properties. They very well could be identical.
Click to expand...
They're not. From AG Russell's Knifemakers Steel Guide.
ATS-34
A high-carbon, high-alloy, stainless steel, a Japanese copy of 154-CM, preferred because it is vacuum melted, and 154 is not. Carbon 1.05%, Manganese 0.4%, Chromium 14.0%, Molybdenum 4.0%.

154-CM
A high-carbon, high-alloy, space-age, stainless steel first used for knives by R. W. Loveless about 1972. At that time it was vacuum melted. Carbon 1.05%, Manganese 0.5%, Chromium 14.0%, Molybdenum 0.4 - 0.55%.
Click to expand...
 
The link from "AG Russell's Knifemakers Steel Guide." has a typo in it.

In their chart 154CM is listed as having a 4.00% Moly. In the text description you pasted they say it is 0.4-0.55%

Spyderco's chart also lists both as having a Mo of 4.00%.
 
The take that I've read here several times is that in the past, US production of 154CM had slipped in quality, and the better knife manufacturers had turned to Japanese ATS-34 for a better product. Now, apparently, US manufacturers have gotten their act together, and a number of companies, most notably Benchmade, have begun using the domestic stuff again.

I have two Benchmades in 154CM and can say that it is definitely high quality material.
 
424,

These are basically the same steel from different countries. While the alloy contents may be slightly different no user (even an expert) would be able to tell the difference between them in use assuming they were heat treated the same.
 
well, one COULD theoretically digest them in acid and do a flame AAS, but that's for the truly anal-retentive :)

my mod trident in 154 has superb heat treatment
rc 60, but not brittle at all

heat treatment = god :D
 
That writeup from A.G.'s catalog was written a long time ago. I believe that the new 154CM made in the States is vacuum melted now. All I know is, it's pretty good stuff when heat treated properly.
 
Okay, I'm confused here.

Isn't the technique called "vacuum smelted"? Is ATS-34 produced with the same particle technique as used by Crucible? I could ask my no-brother-good-in-law, the metalurgist. But then, he might start hanging out at my house like we were buddies.

For example, when I cast bullets, I first MELT the lead. When I add arsenic, antemone (sp?) and tin, heat it and stir it up, then flux, haven't I created an alloy (linotype) by SMELTING?

I won't even get into the smaller grain structure of 154-CM.
 
Vacuum melting is simply a process used to make cleaner steel. Particle technology used by Crucible is totally different and neither ATS34 or 154CM are made by particle technology.
 
Pat Crawford said he'd gone back to 154 CM as it's made in America. He didn't think they handled all that different at least when it comes to grinding the knives. I don't know about cost, though.
 
154CM with the proper heat treatment is as good as Hitach's AST34 IMO and yes 154CM is less expensive of course. I have both on a lot of my knifes and to tell you the truth i can't tell the deference between the two as long as they both have the proper heat treatment.

James
 
Originally posted by 424v8
Is the ATS-34 steel less superior than the 154CM steel. Lately, I have noticed that many knife manufacturer are using less and less of the ATS-34 steel in the production line particuarlly Benchmade. Is it because cost factor??
Click to expand...

Hi,Im a hitachi-metallurgist.154CM of chemical composition is equal to ATS-34.Crucible did not add high Moly of these knife
material easily.So name number of 154CM is larger than ATS34.
They had notice effect of high-Moly at last.Micro-structure
of these material becomes finer by Moly.And also another effect of finer micro-structure exists in maifacturing
process.

The reason of the popularity of ATS34 is to make finer micro-
structure of material, without using a powder-metallurgical process.So ATS34 is not the same material as 154CM.
However,unfortunetlly, by U.S. import-duty raising, cost of ATS34 is higher than 154CMs. So 154CM is not inferior to ATS34 with cost consideration.So ATS34 is most popular high-grade-material now and 154CM is not popular yet in Japan.
 
Thank-you japansteel for coming onto bladeforums and shaing your knowledge! It is always great to have a metalurgist here, especially one from a company who makes a steel that so many knives have been made from.

japansteel raised an interesting point: the difference between steels may be found largest in the tarrif department! 154-CM may be gaining popularity over ATS-34 largely because of somewhat recent US tarrifs laid to protect the US steel industry! I'm sure I couldn't find any difference in use if I had 2 identical knives made, one from ATS-34 and 1 from 154-CM.
 
I can share some history as it came to me. Boeing was using steel as the fins in their new jet engines. The steel was getting hot which caused grain size to increase. It was an incrememtal increase, but collectively, it was enough enlargement of the fins to cause the fins to touch the housing.

Crucible developed 154cm to solve this problem. Adding moly to the mix prevented a phenomena known as "high temperature creep". This kept the grain size from growing.

Bob Loveless, who is always (still is) seeking and experimenting with steels, discovered this steel and found that the mix provided some nice qualities for custom knives. The only disadvantage was the relatively high heat treating temperatures, caused by the addition of the moly. 154cm (chrome/molybdenum) steel became the exotic steel of the day.

When Boeing converted from steel to titanium for the fins, the need for large quantities of 154cm vanished, so Crucible was then only making them for the knifemakers. Not enough volume to keep the very close tolerances, so the steel was not as pure.

As I understand it, a few of the Custom Knifemakers Guild members went to Hitachi and asked that the steel be produced to the original specs of 154cm. Hitachi responded with ATS-34. ATS-34 became the standard of measurement for almost 10 years.

Spyderco began using Crucibles powdered metal (CPM-440V) in production in the 90's. This caught Crucibles attention and they began to look into knives again.

Now Crucible is very active in the knife making community with open ears and good information transfer. They are quickly gaining back the lost 154cm business with very clean mixes at very competitive prices. They have also gone the next step and produced the new knife steel CPM-S30V. This steel has tested extraordinarily well in abrasion resistance and toughness. It is also acceptable in corrosion resistance. A high carbon/nitrogen steel, it is very noteworthy. IMO, I think as time goes on, Crucible will continue to advance and provide us with USA made steels we can be proud of.

sal
 
A few other corrections:

ATS-34 isn't vacuum re-melted (VIM/VAR), it's manufactured using the AOD process (argon/oxygen/decarburization), just like 154-CM. That's a standard process for high-quality standard steel. Very few sttainless steels are vacuum remelted -- BG-42 is one.

Also, the reason knifemakers went away from 154-CM is most arguably because Crucible stopped making 154-CM available in sizes useful to knifemakers. 154-CM started becoming popular again when Crucible started targeting the cutlery industry again. Tariffs against ATS-34 couldn't have hurt, either!

Anyway, the claims that ATS-34 was VIM/VAR and that Crucible's quality slipped are both hard to affirm -- I used to repeat that line in the FAQ, but found that the evidence pointed to the contrary, that ATS-34 is AOD and that Crucible's main problem was stock size.

Joe
 
Originally posted by Ichabod Poser
Okay, I'm confused here.

Isn't the technique called "vacuum smelted"? Is ATS-34 produced with the same particle technique as used by Crucible? I could ask my no-brother-good-in-law, the metalurgist. But then, he might start hanging out at my house like we were buddies.
Click to expand...

Hi Ich,

The process is formally called Vacuum Induction Melting / Vacuum Arc Remelting (VIM/VAR) -- in shorthand, people call it "double vacuum melting" or "vacuum remelting".

Joe
 
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