Is 154CM really more wear resistant than 440C?

Larrin

Larrin

Knifemaker / Craftsman / Service Provider
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Crucible lists 154CM as having 20% better edge retention than 440C, but no information on hardness is given: http://www.crucible.com/PDFs/DataSheets2010/dsS30Vv1 2010.pdf

154CM is typically heat treated to a higher hardness than 440C since 440C seems top top out around 59 Rc before it gets brittle. So perhaps it could be assumed that the 440C used in Crucible's test is at a lower hardness, the the exact numbers are unavailable.

However when Bohler did CATRA testing they got nearly equivalent numbers for 440C and 154CM even though the 154CM was 2 Rc higher: http://www.bucorp.com/media/CATRA_Test2.pdf

Also Carpenter reports that their PM BG42 is lower in wear resistance at an equivalent hardness to 440C: https://www.alphaknifesupply.com/Pictures/Info/Steel/CTSB75P-DS.pdf

Therefore I would conclude that 440C may actually have superior wear resistance to 154CM but when 154CM is heat treated to higher hardness they are more or less equivalent.
 
That isn't all that relivant if they aren't used at the same hardness. Assuming both are heat treated to their greatest potential, 154cm will make a better knife than 440c
 
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if you cant take 440C past a certain hardness before it gets brittle, but the other is stable past that hardness isnt one already better?

and assuming proper heat treat, yes. the 154cm has added moly for toughness, and is generally produced at a higher qiality. I havent read anything about poor quality 154cm but i have seen MANY people talking about bad batches of 440C
 
440-c has been given a bad rap for some time now and I would like to chime in. I hunted for many years and used knives made from 440-c and they performed very well. I have made literally hundreds of knives for hunters in 440-c and have had no complaints. That being said I use CPM 154 cm almost exclusively for my knives now. I think it takes a better high polish and is a steel that almost everyone wants. If you are going to field dress more than four deer this fall wouldn't you have time to sharpen your knife? 440-C make an excellent knife if heat treated properly and costs quite a bit less than CPM 154 cm. That's my opinion. Larry

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The progression was 440C was modified by Climax Molybdenum to 154CM. That in turn was modified by Crucible to CPM 154.
The CPM 154 will be inherently tougher than the others .
The steels should not really be compared without comparing all the characteristics including price. The progressions were all improvements of the previous ones.
I'll take the CPM !
 
Alpha Knife Supply said:
I've not read anybody discuss dirty 440C, much less many people. How long ago were these discussions?

Chuck
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I can do some searching. Thinking about it, it could have just been due to poor heat treat, with it being such a ubiquitous steel for so long it is more prone to abuse than a newer and less known steel
 
The CPM process should be enough reason to not be using 440C any more if you gave a choice.
 
At one common supplier, 154CM costs $1.66 more per foot than 440C. Avoiding the confusion of 440 vs. 440A vs. 440B vs. 440C should be reason enough to spend $1.66 more on material for a single knife, I would think, nevermind performance and marketability.

CPM154 is $6.30 more per foot. That might add up if you're a hobbyist, but as far as pricing your knives go, it's still in the noise, the blade will be much more desirable and has the opportunity to perform that much better.

Does 440C have anything to offer a modern knifemaker anymore?

If I owned some I'd use it up, but am having trouble understanding why anyone would buy it new unless explicitly requested by a customer. Hell, I'm in the same boat with 154CM now. Wish my leftover stock was all the CPM version.
 
daizee said:
Does 440C have anything to offer a modern knifemaker anymore?
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I'm sure 440C can make a decent knife. I was just surprised by my findings because I always thought that 154CM had significantly more wear resistance than 440C; however, it appears that the main benefit is a higher working hardness. And that is probably still plenty reason to switch, I just thought it was a more clear cut improvement.
 
154CM is the ingot version. CPM154 is the exact same thing as CPM154CM.....and this is the powdered version. I would always choose CPM154 over 154CM and especially over 440C.
 
There was a strong rumor that the CPM version had more Mo . NOPE ,just a rumor .I didn't know that was still out there. There were a number of proposed names also but they picked my choice which seemed to me the better one .
The CPM process is started about 1970. That's when I learned of it from some knife makers .Unfortunately I was not involved with knives then except for using them ! :)
 
Note .. the Sub-zero treatment is -75 C [ about - 100 F ] , NOT cryogenic cooling which is about - 300 F . Some steel companies are confused about that !
 
Alpha Knife Supply said:
I've not read anybody discuss dirty 440C, much less many people. How long ago were these discussions?

Chuck
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I bought a few 1.5" X .187" X 36" bars of 440C from SB Specialty about a year ago. Every bar had "spots" every 8-10 inches. They were 3/16-1/4 in dia and were barely visible. Most people never even noticed them but I knew they were there and they drove me crazy. CPM all the way from now on.
 
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