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searching for definitive source on metal for knives

i am getting interested in knives... i know some basics, but am stumped by the metals and how the knives are forged. I also know that different brands, like pots and pans, use different formulas. My question is - can anyone point me to some sort of basic text or videos i can study to begin from the ground up, so to speak? I feel like i'm just getting opinions on "which knife is better because.." I know we all have opinions - especially the manufacturers. I'd like to form my own opinion, but can't find anything to begin a basic steel education for myself. I feel like i missed the basics, but everyone is telling me which knife to buy because THEY say it's best!

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  1. Once a certain point of quality is reached, steel is of lesser importance than heat treatment, grind, and profile.

    Don't get caught up with forged vs. stamped. Powder steels (i.e. high-tech cutting edge steels) are stamped because they can't be forged without losing their advanced properties, and high quality very pure carbon steels are still the reigning champion in forged Japanese knives.

    In general, the higher the carbon content, the harder the steel can be heat treated. Alloying metals like chromium increase corrosion resistance when they aren't pulled into carbide formation. Alloying elements like vanadium and tungsten, which in small quantities reduce grain size and increase toughness, in large quantities create very hard carbides that may or may not be useful in a kitchen knife--while I have S90V (a steel with a stupendous 9% vanadium content) I'm not sure it would be as good choice in the kitchen as something like Aogami Super (which has 0.3 - 0.5%).

    What's problematic even if you start comparing steels (e.g. VG-10) is that different manufacturers (e.g. Tojiro vs. Shun) will have different heat treatment "recipes" for the steel, which can have an enormous impact on how well a knife takes, holds, and keeps an edge. A knife made with Aogami Super heat treated to 63-65 HRC will behave noticeably differently than an Aogami Super knife treated to 60-62 HRC (compare a Masakage to a Hiromoto AS).

    If you want just a listing of steels, zknives is a good resource and he even made an app for Android/Apple:

    http://www.zknives.com/knives/steels/...

    The best way to learn, though, would be to try out different steels for your self. I've bought, sold, and traded knives just to try different steels. There's a good sized knife community that does just this.

    2 Replies
    1. re: Cynic2701

      <If you want just a listing of steels, zknives is a good resource>

      Just noticed that you and I independently point to the same source.

      <Once a certain point of quality is reached, steel is of lesser importance than heat treatment, grind, and profile.>

      I would even argue that for most home cooks the ability to keep a knife sharp is far more important than picking the best knife steel. The knife (handling) skill is even more important. First of all, all knives eventually go dull. So a dull edge on a great steel is still a dull knife. A knife sharpening strategy is important. Second, a good knife blade can only shine with the proper/sufficient knife sharpening skill. Kind of like cooking too. You and I can buy the best chicken, but if we cannot prepare/cook, then it won't really matter.

      1. re: Chemicalkinetics

        Very true. It won't matter how thin of bevels a knife can take, or how long it can hold an edge, if you can't get it on there in the first place.

    2. I've not bother to collect any sites on that - must be some.

      there is no answer to your question, because the question is much too broad and simple. and as the knife nuts will convey, knives are not so simple.

      the various alloys aim at producing a hard steel that will take and hold a micron edge.

      the harder steels tend to chip; nothing like a big haunking chip out of a $1200 knife to make your day. it happens - over the years I've seen some really ugly pictures of really expensive knives.....

      here's one of my personal favorites: "I was able to slice four apples before having to take the knife back to the stones."
      think on that for a minute....I'd go for four bushels of apples, but having to 'go back to the stone' after four apples is not my cup of applejack.

      then there's a Alloy x is better because I use stones harvested from the north face of Mountain Y. Alloy B doesn't work well with Stone Type Q.

      I keep my knives sharp. I use an EdgePro, my finest stone is 1200 grit. compared to the knife nuts using 12000-20000 grit, posting pictures of the newspaper reflected on the cutting edge, etc. etc., is laughable. but it works very well for me.

      and a 10,000 grit of Stone Type A is not the same as a 10,000 grit of Stone Type B - so, there's a lot of stuff to learn about.

      the thing is to match your needs to your passion for sharpening to your budget.
      I go to the grocery store regular, I do not need a Formula One race car to get there. besides, my Yugo has a trunk.....

      1. Hi, rmarisco:

        You pose a very interesting question. I suggest you buy a few basic books on knife *making*. It is the small custom makers who drive the trends in steel selection and fashion. See what the makers--who are the people responsible for what really goes into a finished knife--prefer.

        However, few of these people (and even fewer "knife nerds") have true metallurgical expertise. What virtually everyone goes by is anecdotal evidence, personal preference, and limited involvement. The most glaring example of this is folks who buy a knife or 8, and blindly trust the published specs. Is the blade *really* as hard, or tempered correctly? How meaningful, really, are comparisons with a tiny statistical sample using blades whose features and treatment are already locked in? Is cutting hundreds of pieces of sisal rope determinative?

        The unsettling truth is that, if many, many tool steels are treated properly, they perform very well. I would go as far as to say they are far more similar than dissimilar. I have made knives in 1090, 1095, 52100, D2, L6, ATS-34, 154CM, 5160 and several flavors of damascus as well as some mystery steels. IMO/E, none has been so clearly superior as to call it "best" and have that term mean much. This is one major reason why there is a plethora (aka morass) of opinions, and not much else on the topic.

        Makers tend to choose specific steels because they like *working* with them. It was hard for makers to work with 52100 when it required forging billets from 4" ball bearings. Now you can buy hot-rolled 52100 barstock. Certain steels, e.g., VG-10, are notorious for eating belts, so some makers think that makes for a better end product.
        5160 makes a hell of a knife--if you can find surplus John Deere loadshafts or railcar springs for your triphammer. D2 and others are like comets which depart and return from the system. It can be a PITA to oil quench and air harden, but A- and O-type toolsteels make fine knives, too.

        I'm not saying anyone's completely wasting their time looking for a combination of properties in a knife steel they can conclude is best. But at the same time, I find it pretty thin gruel, both as a maker and a user.

        Aloha,
        Kaleo

        2 Replies
        1. re: kaleokahu

          aloha to you Kaleao,
          your answer is what I have suspected all along...steel must be more similar than dissimilar, and I don't need to sweat it so much. I think this is a gearhead problem - "my engine is better than your engine" type of thing. I think I'll watch a bit, read a bit, and not stress over it! Just enjoy the beauty of the knives...

          1. re: rmarisco

            Hi, rmarisco:

            I think your engine analogy is quite apt. Handguns may be another.

            Yeah, I say relax, learn as much as makes a difference to you, and enjoy.

            Aloha,
            Kaleo

        2. A Primer on Steel (about 18 minutes):

          https://www.youtube.com/watch?v=jkLsL...

          Forging a Knife (About 19 minutes):

          https://www.youtube.com/watch?v=HrasE...

           
          1. I had 2 semesters of steel courses in my engineering undergrad study and understanding steel requires an understanding of its phases (based on heating/cooling) as well as the effects of different amounts of carbon - and that's BEFORE you start getting into alloys. In short, not something you can pick up in a youtube video. I was recently gifted a $500 chef's knife, which is beautiful and feels great in my hand, but isn't any more functional than a $100 Gerber I've owned for 20+ years.

            15 Replies
            1. re: ferret

              thanks ferret - it's good to know that price doesn't necessarily reflect quality.

              perhaps it reflects marketing as much as anything!

              1. re: rmarisco

                When I consider the knives that I use most, and ones that are stuck in the back of some drawer, cost was not a factor. If anything, it's the least expensive ones that get most use.

                Blade shape, weight, size, and handle design are far more important than steel. And in most cases I learn which I prefer most after buying and trying.

                1. re: paulj

                  I recently purchased a 2-pack of Kirkland "Professional" chefs knives from Costco for about $14, thinking it's always good to have some spares. They're surprisingly good. Do I think they'll last years? -- way too soon to tell. But you can do a lot worse for $14.

                  1. re: ferret

                    A homecook probably will become dissatisfied with a knife before it breaks.

                    Butchers wear down knives through constant use and sharpening.

                    I've had a Chinese cleaver break at the tang - rust plus a small tang in a round wood handle. But it is easy to find inexpensive knives with a full tang. Even knives with molded plastic handles will have fuller tang than older ones with a round wood handle.

                    Chipping is possible - but more likely with excessively hard steels (or harder ceramics).

                    There aren't many other ways in which a knife will break or wear out (assuming you know how to sharpen them).

                    1. re: paulj

                      Global's seemed to have an issue with shattering a few years ago. There's a picture of Grant Achatz having his Global snap in his hands:

                      http://twitter.yfrog.com/i33dtsj?sa=0

                      The issue seems to have been resolved, as I haven't heard of Global's snapping in quite a while.

                      1. re: Cynic2701

                        These hollow-handled integrals are trouble, period, in my book. Globals just feel like they're going to break to me.

                        Chris Reeve's survival blades are strong enough, because they are true integrals and are much beefier.

                        1. re: kaleokahu

                          I replaced that broken cleaver with a stainless integral handle one - but ended up passing that one on to my son. It was too difficult to sharpen. I've moved on to the lighter weight Japanese style Nakiri.

                          If I need to attack a hard squash, I can always pull out my Cold Steel Bushman. That has an integral handle that won't snap.

                          http://www.coldsteel.com/Product/95BU...

                          1. re: paulj

                            Hi, Paul:

                            I woulda had you figured for a Trail Master.

                            Squash beg for a hatchet.

                            Aloha,
                            Kaleo

                            1. re: kaleokahu

                              Lynn Thompson is a shameless design thief and snake oil salesman, who does not stand behind his products. Sorry for the incendiary comment, but he is very reviled in the knife industry, and stolen designs from friends of mine who are knife makers.

                              FWIW, I'm a Strider user when it comes to tough knives. Dwayne Dwyer, Mick Strider and Josh Lee make a great knife, are tremendous supporters of the military and LEOs, and have the best warranty in the business.

                              1. re: wabi

                                Hi, Wabi:

                                Good recommendation. The "sharpest knives in the world" claim tells us a lot.

                                Cold Steel and SOG have always seemed 'recreational tactical' to me. The Bushman design appeals to me only because it can be hafted.

                                Aloha,
                                Kaleo

                                1. re: kaleokahu

                                  I drive past the SOG offices in Lynnwood quite often. They have a 'outlet store' sandwich board outside, but when I went in once years ago, it was just some clerk's desk drawer of 'rejects'.

                                  1. re: paulj

                                    One of my car mechanics has his shop a block away from SOG building. I've never seen anything remotely resembling a deal there. IMO, the whole "tactical" market is 95% bullshit.

                          2. re: kaleokahu

                            Yeah, Chris Reeve's stuff is fantastic. I have a left handed Umnumzaan and a left handed large Sebenza.

                            I wish I had picked up an integral while he still made them. If you have one, hold on to it because they are climbing in price since they aren't being made any more.

                            His kitchen knives look interesting, but a bit too odd (I'm not convinced they would be worth it).

                        2. re: paulj

                          I don't think full tang is that much better than partial tang. As long as the partial tang is reasonably made, there shouldn't be a problem. Moreover, a knife which snaps at handle/blade junction section has nothing to do with being full tang or not -- a longer tang won't help.

                          Cynic is correct that Global had some issue of knife snapping at the handle/blade junction, but that issue appears to have been resolved.

                          More than often, knives tend to break at the tip when they are incorrectly used.

                          1. re: Chemicalkinetics

                            Yes, it's the heft of the tang at the blade base that matters, not so much the heft at the tip.