1. Welcome to the New & Improved BladeForums. New software info here. Please report problems in Tech Support, and read existing threads before posting! - Spark
  2. I've changed the default forum style to Flat Awesome based on feedback. Don't like it? Click here to change how the forums look Feedback on this is welcome here.

ATS-34 versus 154cm

Discussion in 'General Knife Discussion' started by spyderco lover, Feb 29, 2012.

  1. spyderco lover

    spyderco lover Banned BANNED

    Feb 27, 2012
    I recently received an old American made Benchmade Ascent in ats-34, and it seems to me that it produces a finer edge than the 154cm I had on the 940. Does anyone have any experience comparing the two? I've also experienced 154cm from Gerber in their applegate folder, and a griptilian, but this Ascent seems to smooth to a thinner cutting edge after stoning and stropping it.
  2. Tsujigiri


    May 25, 2009
    You might be thinking of CPM-154CM, which is the particle steel version of 154CM. It is finer grained.
  3. spyderco lover

    spyderco lover Banned BANNED

    Feb 27, 2012
    I don't have any experience with the new (and more expensive) CPM version, I'm just curious why my ATS-34 slices newspaper easier than the 940 did.
  4. RevDevil

    RevDevil Super Evil Supermod Staff Member Super Mod

    Nov 9, 2009
    No such steel as CPM-154CM. It's either 154CM or CPM154, the latter being made with the partical metallurgy process. As far as 154CM and ATS-34 are concerned, they are very, very similar, ais VG-10 and even RWS. ;)


    The slicing of newspaper might be attributed to the fact that the latter knife was just sharper than the former?
    Last edited: Feb 29, 2012
  5. spyderco lover

    spyderco lover Banned BANNED

    Feb 27, 2012
    It's possible, I tried to sharpen them the same but either way they both take outstanding edges and maintain them exceptionally. As for vg-10, do you find it easier to sharpen than 154?
  6. RevDevil

    RevDevil Super Evil Supermod Staff Member Super Mod

    Nov 9, 2009
    I usually use a sharpmaker for VG-10, it's about the same in my eyes. Once again, I think different manufacturers have different formulas for the heat treat though.
  7. res1cue


    Feb 2, 2010
    Probably more of a grind and edge geometry thing rather than the steel. Really you shouldn't be able to tell between them, or any other similar steels
  8. Tsujigiri


    May 25, 2009
    Thought that sounded a little unwieldy, although I was sure there was a particle steel version...

    Spyderco Lover: Spydercos usually have thinner edge geometry than most other knives, so they tend to slice better and seem sharper, even if they aren't. Are you comparing a thin blade to a thicker one?
  9. spyderco lover

    spyderco lover Banned BANNED

    Feb 27, 2012
    No they're two benchmades, and I reprofiled both to 17 degrees then stropped them. They're almost the same in thickness, a difference of about .3 millimeters. Its a small amount, but I can feel slightly less resistance with the ATS
  10. ginaz


    Apr 19, 2001
    i had a Benchmade 905 in ATS-34 and i remember that steel taking a particularly sharp edge. compared to it, i was never impressed with 154-CM
  11. knarfeng

    knarfeng senex morosus moderator Staff Member Super Mod Moderator

    Jul 30, 2006
    IIRC Custom maker RJ Martin, who has a degree in materials engineering, had some metallographic studies done on samples of ATS-34 and 154CM in about 2005 or so. He posted that the studies showed the 154CM had the better grain structure than ATS-34. I also remember that there was a time in the late 70's or 80's when ATS-34 was more consistent was decidedly better than 154CM.

    But in your own assessment, you are leaving out a major variable. Aside from geometry and alloy, there is also hardness. If you do not know to what hardness each blade was heat treated, you really cannot make a comparison. I've seen a difference in hardness of a a point or two make such a difference as you describe.
  12. spyderco lover

    spyderco lover Banned BANNED

    Feb 27, 2012
    I actually did email benchmade specifically asking their ats-34 heat treat so that I could compare that factor, still waiting for a return email.
  13. RxEnergy


    Apr 2, 2008
    a) I doubt anyone in customer support worked @ BM back when they were still using ATS-34
    b) Even if they ask someone who did, the info is most likely a trade secret, or too complicated to relay through third person and I doubt anyone from HT department will sit down to answer an email like that.

    As to the OP, I really like slicing abilities of old Crawford Leopards in ATS-34. And still, I feel that all it comes down to is HT and edge geometry.
  14. marthinus

    marthinus KnifeMaker / Craftsman / Service Provider Knifemaker / Craftsman / Service Provider

    Dec 10, 2006
    Ats-34 was seen as the be all end all of steels when it became popular, now we think M390 can be it. Wow how far have we come.

    154CM had some major manufacturing faults for a while. Air pockets in the steel. The push for Ats-34 was big, however 154CM resolved the problem.

    Now, they both have similar composition to my knowledge (can't check my resources at this time), but, heat treat as well as EACH RUN of the steel can have some slight variables resulting in different carbide formation resulting in a slightly course feeling edge or maybe not.

    Comparing two knives, with different runs of 154CM can also result in what you are describing, its all small variables.

    You might get another ATS-34 blade giving more resistance like the 154CM knife through news paper.

    IMO the new RWL-34 (powdered ATS-34 named after Bob Loveless) and CPM-154 are the best balanced steels for the user and maker on the market and at HRC of 62 is excellent. It can handle fine and course edges and hold them for some time in my uses due to the 0.2% Vanadium giving excellent balanced carbide formation.

    The packaging of the last two steels mentioned is also excellent from the factories, carbonised is removed and is perfectly flat, thus reducing the cost to the maker to do it on his own.
    Last edited: Mar 1, 2012
  15. JNewell

    JNewell Gold Member Gold Member

    Nov 18, 2005
    I have 710s and 705s in both ATS-34 and 154CM. There may be metalurgical differences, but I've ever noticed any difference between them in real life use. In spite of super-steel developments in the last decade, both are still pretty darned fine choices for a knife blade.

  16. arty


    Oct 18, 2003
    ATS34 is the Japanese version of 154CM. Heat treatment varies, and that could explain any differences.
    I find my knives in VG10 are easier to sharpen by hand, but that is probably because the blades are somewhat thinner behind the edge.
    Wear resistance is pretty good for any of these steels.
  17. mete

    mete Gold Member Gold Member

    Jun 10, 2003
    Air pockets in steel ??? NO ! You might be talking about inclusions that have been pulled out during polishing. ATS-34 and 154CM are essentially the same as for chemistry. However over the years they have varied due to variations in the steel making process and QC.Sometimes ATS-34 is better and sometimes 154CM at any point in time . Try CPM154 and RWL-34 and you'll be happier .
  18. marthinus

    marthinus KnifeMaker / Craftsman / Service Provider Knifemaker / Craftsman / Service Provider

    Dec 10, 2006
    Hi mete, could you elaborate a bit on this? All I can remember was something mentioned that some were grinding 154cm and then, no steel like a air pocket. I am running on a foggy memory on this. See if I can find where I read it.
  19. marthinus

    marthinus KnifeMaker / Craftsman / Service Provider Knifemaker / Craftsman / Service Provider

    Dec 10, 2006
    Nope, cant find it, forget what I said about the air pocket thing.

    Here is something I found while looking around. Posted back in 2000

    A lot of companies and makers are turning from ATS-34 to (or rather, back to) 154CM. The two steels and nearly identical, ATS-34 being made by Hitachi and 154 CM by Crucible. The standard knife lore is that knifemakers originally used 154CM, then found that its quality of manufacture became suspect and switched to ATS-34. People have been asking that, given the quality problems, why are companies switching back to 154CM. The response is that 154CM is now being manufactured to very high quality standards, equal or superior to ATS-34.

    I asked Crucible about this, and here is the reply from one of their metallurgists:

    Let me give you a time line of where this grade was and where it is

    Our steel mill is a rod and bar mill. 15 or more years ago, we did
    not produce sheets of steel, but instead rolled thin bars. Thin bars
    were the preferred material for stock removal blades. 154CM was a
    bearing material produced primarily in round bar form for that market.
    The cutlery end of the grade was a side market and since the stainless
    bearing market is not huge kept the volume up. Crucible marketed this
    grade primarily through knife supply houses and really didn't come
    into direct contact with the knife industry.

    One myth from that time that continues to plague the grade is that
    154CM was vacuum re-melted. This grade was never produced with vacuum
    re-melt technology. At the time it was air melt material. Today it
    is melted differently, but I'll cover that later.

    As the stainless bearing market continued to shrink, it became more
    difficult to justify an 80,000 lb heat of 154CM, especially for the
    smaller cutlery industry. At the same time, the industry converted to
    using sheet product, which allowed lazer cutting and more versatiliy
    of widths. Put all this together with Crucible having no direct
    contact with the market and guess what, we were out of the business.
    Take a note of how many supply houses carry sheets of steel. None.

    A little over 10 years ago the distribution part of Crucible became
    it's own divison. The number of warehouses doubled and this division
    became very intimate with its markets. The Service Center Divsion is
    not limited by the mill's production and can convert material using
    outside sources (i.e. sheet products). With this in mind we entered
    back into the 154CM, 440V, 420V,etc. business and intend to stay there
    for quite a while. We dove back in about 3 years ago with the help of
    one of the larger knife producers and have been getting better every
    year. The mill still melts the material, but we stock the sheets in
    our warehouse system for cutting into various sizes.

    Now this brings us to the material production. Like I said earlier,
    many years ago, this material was produced by air melt technology.
    Today it is produced by the Argon/Oxygen/Decarburization process
    (AOD). This is the primary way to produce quality stainless steels.
    It is not as clean as re-melted steels but is about as close as you
    can get and is much cleaner than 15 years ago. 3 years ago when we
    entered back into the 154CM market we were concerned that the ATS-34
    was cleaner than ours. We found just the opposite. They do not
    re-melt their material either and in numerous tests with knife makers
    and polishers our material was much cleaner. Based on our sales and
    responses from our customers, the myth of the dirty 154CM is behind us
    for good.

    Now for the future. We are still adapting to the needs of the market.
    Many of the larger companies purchase full sheets and this is easy for
    us. Cut strips and pieces are another story. Since we can't possible
    stock sheet product in every district (We have 26 warehouses in North
    America) we are setting up one of our warehouses to handle the small
    piece business for the whole country. This project is currently in
    motion and will be completed by year's end. As soon as you see our ad
    in the magazines you will know we're ready.

    If anyone wants to meet us we will be at the Oregon knife collectors
    show in April and we will be at the Blade show, also.

    I still feel we are not completely where we want to be service wise
    but we get better each month. We urge the knifemakers to give us
    feedback good or bad so we can continue to improve.

    I hope this answers your questions, Sorry for being so windy.
  20. marthinus

    marthinus KnifeMaker / Craftsman / Service Provider Knifemaker / Craftsman / Service Provider

    Dec 10, 2006

Share This Page