coyright@dataabc.se

Knivstål och en del begrepp som förekommer i samband med knivar

Vanligaste och viktigaste grundämnena i knivstål är:
  • Fe - Järn/Ferrit
  • C - Kol/Carbon Increases edge retention and raises tensile strength. Increases hardness.
  • Cr - Chrome ökar rosttrögheten. Increases hardness, tensile strength and toughness. Provides resistance to wear and corrosion.
  • N - Kväve/Nitrogen
  • Mn - Magnesium
  • Si - Kisel/Silicium
  • Mo - Molybden/Molubdenium Increases strength, hardness, harden ability, and toughness.Improves machinability and resistance to corrosion.
  • S - Svavel/Sulphor
  • Tu - Tungsten
  • Ni - Nickel
  • Ph - Fosfor/Phosphor
  • V - Vanadin/Vanadinium Increases strength, wear resistance, and increases toughness.
  • W - Tungsten ökar hårdheten Adds strength, toughness, and improves hardneability.
  • Co - Cobalt Increases strength and hardness, and permits quenching in higher temperatures. Intensifies the individual effects of other elements in more complex steels. vissa egenskaper.
  • Lite förenklat kan man säga att vid ståltillverkning läggs olika legeringsämne till grundmaterialet järn för att ge andra önskade egenskaper. Utöver stålkvalitet måste tillverkningsmetod(pulver(PM), kallvalsat eller smitt), design, värmebehandling (normalisering och härdning), form, slipning väljas och vara korrekt utförda. Ett högre legerat härdat stål är svårare att bearbeta och slipa än ett mjukare låglegerat! Man tvingas alltid avväga olika egenskaper, även mot varandra, mot pris och tillverkningskostnad. Därför finns inget bästa eller sämsta knivstål. Hur avväger man t.ex. hur ofta och lätt man behöver skärpa stålet mot hur länge en vass egg skall hålla? Hur mycket mekanisk påfrestning och misshandel skall eggen tåla? Ett segt stål eller ett hårt som gör kniven hård och lätt att bryta. Skall man välja ett billigt kolstål som rostar eller ett rostfritt? Kolstål kan ge minst lika bra, eller bättre, skärpa än rostfria blad! Idag kan man tillverka knivar med valda, även extremt bra, egenskaper i stål specialsammansatta för alla upptänkliga användningsområde. Knivar kan tillverkas med olika stål, i olika form, med olika värmebehandling, med olika slipning, med olika tillverkningsmetoder och även laminerade.

    Carbon steel can have up to 1% carbon and in some cases also small quantaties of other alloys.

    Just to clarify the terminology. Technically and precisely speaking, there is no such thing as stainless steel. What has became an accepted term in the industry isn't correct. All steels will rust, if proper care is not taken. Simply, some steels resist corrosion better than others, and that's all there is to it. Thus, the correct term is stain-resistant. Throughout this document and elsewhere on this site, I use the tern stainless referring to stain-resistant steels. Lately, a lot of kitchen cutlery makers started using the stain resistant term, which in my opinion is a good sign.

  • Kolstål - billigt, härdbart och mycket bra och vanligt stål för knivar.
  • Rostria knivstål är idag det vanligaste och finns idag med olika sammansättning i allt från enkla 12%-iga kromstål till mycket avancerade svårtillverkade högt legerade och kostsamma stålsorter.
  • Idag tillverkas också knivar med keramiska blad, ofta med extremt skarp egg men mycket sköra och lätta att bryta!
  • Det förekommer även knivar med blad av titan.
  • Surgical Steel - Also often referred as Stainless Surgical Steel in many knife promotion materials. Clear sign that you should steer away from that knife. There is no official surgical steel to begin with, just number of different alloys used in medical instruments and implants such as 17-4, 17-4 PH, 455 stainless and for implants - 316L Stainless or titanium 6AL4V, which isn't even a steel(detailed info courtesy of CNC machinist for major medical companies). None of those are known for properties suitable for knives, rather the opposite. They all however are highly stainless. These days, whatever surgeons use is disposable pretty mush 100% of the cases. Do you really want a disposable knife in your kitchen? As far as knife marketing is concerned, the term "surgical" refers to low wear resistant, cheap stainless steels like 420 series or worse. In short, it's bad, stay away.

    Silver steel är en benämning på verktygsstål där silver refererar till metallens färg!

    Borstål användes i yxor, i t.ex. vägskrapor och idag i moderna höghållfasta bilstålkarosser.

    Steel grades are defined in standards like ASTM, DIN, SS ...... and many more.

    Några av alla de otaliga stålkvaliter(stålsorter, stål standards) som finns i handeln idag är:

    C100 - 1,05%C, 0,6%Mn, 0,35%Si, 0,4%P, 0,5%S kolstål

    Sandvik 20C - 1%C, 0,4%Mn, 0,3%Si, 0,2%S, 0,2%P kolstål

    UHB20C fjäderstål / kolstål

    AISI 01 kolstål

    420 Series - Low wear resistance, highly stain-resistant, good choice for diving knives, but nothing interesting for the kitchen. Very low Carbon content, less than 0.3%-0.5%, makes it too soft for a useful cutting tool in the kitchen. Used mainly in very cheap kitchen knives. Skip it. Ref - AISI 420 Steel Composition.

    420J2 - Cr 14%, Ni 1%, Mn 1%, Si 1%, Ph 0,04%, C 0,15-0,36, S 0,03% Fiskars uses this chines steel for beeing inexpensiv and easy to machine! Chines producers call it 3CR13. At least easy to grind and can give good enough sharpness.

    2Cr13 0,15%C, 12-14%Cr, 1%Mn, 1%Si, 0,09%Cu, 0,04%P, 0,03%S

    440A/440B - Not too good to begin with, and haven't seen anyone lately using them for the good kitchen knives. Skip it. A lot of low cost mainstream kitchen knives are made from this or similar steels. Ref - AISI 440A vs. 440B Steel Composition comparison. Cutco uses 440A in their kitchen knives, claiming to be the best, but it's far from it. Wenger använder detta stål.

    8CR13MOV användes av Bubbablades. Ungefär 440B. - C 0,7-0,8 Cr 13-14,5 Mo 0,1-0,3 V 0,1-0,25 Ni 0,2 Mn 1,0 Si 1,0 S 0,03 P 0,04 9CR13MOV - C 0,85 Cr 13,5 Mo 0,2 V 0,2 Co 1,0 Mn 1,0 Si 1,0 S 0,03 P 0,35

    440C - Used to be a premium steel for years, by now it's rather old. Ref - AISI 440C Steel Composition. Still, many makers use it in kitchen knives. Phil Wilson used to use it too. When heat treated properly, it's a decent performer in the kitchen and outside of it as well. The only thing is, factories don't heat treat that steel to those high standards. Therefore, if you can get a custom from the trusted maker, then it is probably worth it, otherwise not that good. Good toughness and stain resistance. Ref - AISI 440A vs. 440B vs. 440C Steel Composition Comparison.

    12C27 - Another old timer. Swedish stainless razor steel. Interesting one, because it's a very pure, fine grained alloy. Ref - Sandvik 12C27 Steel Composition. Takes very keen edge. Edge holding is ok. Several western and Japanese makers use it. It's an ok steel IMHO. If you find a good maker, he'll make a pretty good knife out of it. Nothing outstanding IMHO, but a lot of makers like it, which is understandable, it's easy to work with and lots of knife folks(i.e. customers) like it too. Används av Frost i Mora, gamla nu nedlagda Jernbolaget eller KN i Eskilstuna.

    12C27M Sandvik - C 0.52, Si 0.4, Mn 0.6, P =0.025, S =0.010 Cr 14.5

    13C26 Sandvik - Similar to 12C27, but has less Cr, More C. Identical to Bohler-Uddeholm AEB-L razor steel. See comments there. C 0.68, Si 0.4, Mn 0.7, P =0.025, S =0.010, Cr 13

    14C28N Sandvik - C 0.62, Si 0.2, Mn 0.6, P 0.025, S 0.010, Cr 14, N 0.11 used by Frosts for new chef kitchen knives

    Sandvik Bioline 7C27Mo2 - C 0.38, Si 0.4, Mn 0.6, P =0.025, S =0.010, Cr 13.5, Mo 1.0

    19C27 Sandvik- C 0.95, Si 0.4, Mn 0.7, P =0.025, S =0.010, Cr 13.5

    1.4116 - W-Nr standard name of the X50CrMoV15 steel, which is a DIN standard name. See X50CrMoV15 steel.

    154CM/ATS-34 - 154CM (don't mix with a better CPM154 steel) is the original American steel, and ATS-34 is Hitachi version of it. Good stainless steels, not used in mass production kitchen knives though, too expensive. Some makers use it, in custom kitchen knives. High wear resistance, but brittle at higher hardness. I personally, wouldn't choose either of them for my custom kitchen knife, there are better choices. That's not to say they(154CM/ATS-34) are bad choices, but if I spend few hundreds on custom kitchen knives then I will definitely pick a better steel, and that will add another hundred or so to the total price. Ref - ATS-34 vs. 154CM Steel Composition Comparison.

    AEB-L - Swedish stainless razor steel. Very pure, fine grained alloy. Virtually identical to Sandvik 13C26 Steel. Slightly less Mn and 0.010% more S, ref - AEB-L vs. 13C26 steel composition comparison. When heat treated properly, produces very small, fine grain, which positively affects edge holding, edge stability and toughness. Devin Thomas uses it in his kitchen knives, with very good results. Working hardness in kitchen and light cutting knives is 61-62HRC.

    Cronidur 30 - Same as X30CrMoNi1-5-1.

    Cowry-X - Latest super duper PM steel. Ultra high carbon and chromium content. C - 3% and Cr - 20%. Very high hardness, several makers harden it to 65 or even 67HRC. As you can guess very expensive too. ZDP-189 and MC-66 are very similar, in that those two have the same C and CR content. Exact element makeup unknown. Overall, very good edge holding and toughness. Hard to sharpen compared to other steels, nothing impossible though. So far Hattori is the only one making kitchen knives out of it.

    CPM S30V - Carbon 1.45%, Chromium 14.00%, Vanadium 4.00%, Molybdenum 2.00%. Barber received feedback from a number of other knife users and knifemakers such as Sal Glesser, Ernest Emerson, Tony Marfione, Phil Wilson, William Harsey Jr., Tom Mayo, Jerry Hossom, and Paul Bos in the development of CPM S30V. CPM S30V is considered a premium grade knife steel. It is so expensive that it strongly affects the price of the knife, and is largely used in higher-end production and custom knives. Buck Knives calls it "the absolute best blade steel available".[5] Joe Talmadge claims it might be the ultimate high-end all-around stainless steel, due to high performance coupled with easier machinability and sharpenability than the other steels in this class.[6]

    CPM™ 154 - Crucible Particle Metallurgy version of 154CM. Significantly better then it's predecessor. Purer steel, with finer carbides. Elemental makeup is identical to 154CM, however, rumors are CPM154 contains small amounts of Vanadium, thus being more wear resistant, however Crucible representative stated Vanadium in the alloy is residual, not intentional. Toughness and finishing properties are increased considerably. Easier for makers to work with, and for the user it means quite tougher, little but more wear resistant and finer edged knives. Several custom makers use it for kitchen knives, no factory knives in CPM-154 though. Phil Wilson makes fillet and chef's knives out of it. Can go up to 61HRC, although not many makers take it there. Very good choice. Ref - AISI 154CM vs. CPM154 Steels Composition Comparison.

    CPM™ S90V(CPM420V) - CPM S90V (420V is the old name) is a very high alloy steel from Crucible Particle Metallurgy. Very high wear resistance coupled with very high corrosion resistance. Ref - CPM S90V Chemical Composition. As you can see alloy content is extremely high. Because of the very high Vanadium content it's really difficult for the makers to work with. Upper limit for hardness is 61HRC. For now, the only maker I know of, making kitchen knives with S90V is Phil Wilson. Sadly, Phil isn't making large kitchen knives anymore. On the other hand, paring knife from S90V or even small chef's knife is also a very good choice. Perhaps I'll get one later too. I have S90V Lochsa folder from Scott Cook, heat treated by P. Boss to 60HRC. Very good edge holding. Definitely a good choice for a quality kitchen knife if the maker knows how to work with it.

    CPM™ S110V - CPM S110V is another very high alloy steel from Crucible Particle Metallurgy. Very high wear resistance coupled with very high corrosion resistance. The news is the addition of the Niobium - Nb. Ref - CPM S110V Chemical Composition. As you can see, alloy content is extremely high in S110V too. Because of the very high Vanadium content it's really difficult for the makers to work with. Recommended hardness by Crucible is 61-63HRC. Although, Phil Wilson did manage to get it to 64HRC and make exceptionally good cutters out of it. For now, the only maker I know of, making kitchen knives with S110V is Phil Wilson. The real problem with the steel is that it's pretty hard to get from Crucible in knife making suitable sized bars. Edge holding ability is even greater than that of the CPM 125V and CPM 10V. Mainly because of the addition of the 3.5% Niobium. Nb carbides are very hard, harder than Vanadium carbides, and overall carbide volume is very high in this alloy. Thus, wear resistance and edge holding for abrasive cutting is extremely high.

    CROMOVA 18 - Yoshikin proprietary stainless steel for their brand Global knives. Cr indicates Chrome in the alloy, Mo is for Molybdenum and Va is for Vanadium. Exact chemical composition was unknown, except for 18% of Chromium in it, which is what 18 stands for in the name of the steel. Eventually it became known that Cromova 18 was a rebrand of the Aichi AUS-118 steel. Better performer compared to X50CrMoV15 types of steel. Highly stain resistant with pretty good edge holding ability. Ref. - Cromova 18 steel composition. Cromova 18 - C 0,9-0,95, Cr 17,8-18, Mo 1,3-1,5, V 0,1-0,25, Mn 0,25, Si 0,5, P 0,04, S 0,03

    MC66 - Henckels current alias for the Hitachi ZDP-189 PM steel. MC stands for Micro Carbide and 66 is the target hardness on the Rockwell scale. Used by Henckel in their Twin Cermax and Miyabi 7000MC lines.

    SRS-15 - Japanese Powder Metallurgy(PM) steel. Excellent choice for kitchen knives. Ref - SRS-15 PM Steel Composition. As you can see, it's really high on Carbon, and all that Tungsten with Vanadium increase wear resistance significantly. Overall, it can get to 64-65HRC no problems. Akifusa gyuto that I have, is made of SRS-15, and I can only attest to its excellent performance.

    SG-2 - Japanese Powder Metallurgy(PM) steel. Made by Takefu steel company. Excellent choice for kitchen knives. Also known as SGPS, well Fallkniven uses it under that name. As far as I know SG2 stands for something like Super Gold. For curious minds - Takefu SG2 steel composition. Shun uses SG2 steel in their elite line. It's a good steel, according to other accounts, less of a performer compared to SRS-15. Although, I've seen quite negative comments on SG2 performance in Fallkniven U2 folder. On the other hand, folks seem to be happy with SG2 performance in Shun elite knives. Achieves very high hardness, Shun Elite knives are officially 64HRC, although lately 62HRC figure is cited quite often too. Ref - SRS-15 vs. SG2 Steel Composition Comparison.

    SKD11 - Japanese tool steel. It is same as AISI D2. Stain Resistant, not truly stainless. Very good edge holding. Yoshikane uses this steel for their kitchen knives, hardened to 64HRC. Most of the reports I've seen are very positive. Some indicate microchipping along the edge. Though this is perhaps related to sharpening angle. For the record, I haven't seen western kitchen knives in D2 steel. Ref - SKD11 Steel Composition.

    S30V - Quite good cutlery steel. CPM S30V was developed by Crucible Metallurgy with knives in mind, which is very rare in the industry. Apart from Shirogami and Aogami steels, I don't really know any others created for knives. Based on very tough and wear resistant CPM3V. Has added Cr and other elements. Although, it has added too much chromium and Carbon to be as tough. Can get pretty hard, up to 62HRC. Better wear resistance than 154CM. It was quite hyped up back in early 2000 when it first appeared, but proper heat treatment isn't that simple and several manufacturers and even custom makers produced knives that were either too soft or chipped easily. Obviously that didn't work well for S30V reputation. Also, compared to many other alloys this one is more difficult to machine and process. Perhaps that explains why some makers choose to run this steel at 58-60HRC. Haven't seen many S30V at 62HRC to be honest. Phil Wilson is really good with this steel, and makes kitchen knives out of it. Unfortunately, Phil is shifting his focus mainly to smaller fillet, chef's and paring knives. Longest being 6"-7". S30V is pretty popular with other makers. I have Trace Rinaldi TTKK, that I've used in the kitchen for years. It's not exactly a kitchen knife, but held up pretty well. For very good information regarding this steel I highly recommend Phil Wilson's CPM S30V Introduction. Ref - CPM S30V Steel Composition.

    VG-10 - Very good stain resistant steel. Used widely in Japanese kitchen knives. From western makers Fallkniven uses it in some of their blades like K2 - White Whale. Most of the Japanese blades are 60-61HRC, except for Tojiro, who makes them at 62HRC, Tojiro Santoku, Tojiro Paring. Fallknivens are 59HRC. Old, but very good performer. Needs minimal care to avoid corrosion. Takes very good edge and easy to sharpen even at 62HRC. Good edge holding. Ref - VG-10 Steel Composition

    X30CrMoNi1-5-1 - Also Cronidur 30. Stainless steel, used in aero-space industry. Henckel uses it in their limited edition knives. For a while I didn't think much of Cronidur 30 steel, even though I knew it had Nitrogen in it. Later, one of the German knife guys pointed out that the amount of Nitrogen in the alloy is quite high 0.40% and more. So, overall the steel should exhibit properties of high carbon steel. Good wear resistance and relatively good toughness too. Still, 1000$+ price tag is very high for the knife of this steel. Bohler-Uddeholm Vanax 35 steel and Vanax 75 Steel, both have much higher Nitrogen content in them, 1.35% and 4.20% respectively and the knives out of those steels cost much less too. Plus Vanax series steels have Vanadium in them, which definitely helps with abrasive wear resistance. Ref - Cronidur 30 (X30CrMoNi1-5-1) Steel Composition.

    X45CrMoV15 - German steel. Similar to X50CrMoV15 steel. As you can deduce contains 0.45% C. Nothing interesting. Used by several western makers including F. Dick. Technically and practically, this is not a high carbon steel. Medium it is. Ref - X45CrMoV15 steel composition.

    X50CrMoV15 - W.Nr 1.4116 German steel. Very stain resistant. Other than that not much to speak of. The cryptic X50CrMoV15 stands for 0.5% carbon, the other 15% is composed of 14% or 14.5% of Cr, some Mo and V. X in the name is a an indicator for high alloy steel, 0.5% C content means, by definition X50CrMoV15 isn't a high carbon steel, despite of some marketing claims. In fact it has less C content compared to 440C steel. However, it's plenty tough and resists corrosion well and it is a high alloy steel. If you don't want to bother maintaining your knives this is a good choice. Except for the low edge holding ability of course. In the end, you end up sharpening it a lot more often, so low maintenance statement is really arguable. Used by Wusthof, Victorinox and others in their high end knives. Ref - X50CrMoV15 Steel Composition. If you are interested, you cn also read up on DIN And EN Steel Standards Naming Conventions. (Wenger använder även detta stål.) Jero använder detta stål från Outokumpu. Victorinox använder det i sin Fibrox serie. Victorinox anger 15Cr, 0,5Mo, 0,45Mn, 0,6Si

    X55CrMoV15 - Variation of 1.4116 steel. Pretty much the same, except for the slightly higher C content - 0.55%. Used by Messermeister. Not sure who else uses it. You can see the detailed differences in composition on this X55CrMoV15 vs. X50CrMoV15 steel composition comparison graph.

    ZDP-189 - Latest super duper PM steel. extremely high carbon and chromium content. C - 3% and Cr - 20%. Very high hardness, several makers harden it to 65 or even 67HRC. As you can guess very expensive too. Cowry-X and MC-66 are very similar, in that those two have the same C and CR content. Although, Henckel representative in Tokyo did confirm MC66 being ZDP-189. Exact element makeup unknown, whatever I have in the Knife Steel Chart is not confirmed by Hitachi. Unlike Cowry-X, ZDP-189 contains Molybdenum, Tungsten and Vanadium. Overall, very good edge holding and toughness. Hard to sharpen compared to other steels, nothing impossible, really. Ref - ZDP-189 Steel Composition.

    D2 - C 1,5 Si 0,3, Cr 12, Mo 0,8, V 0,9

    G3 - C 0,15 Mn 1,0 P 0,04 S 0,03 Cr 21-23,5 Mo 6 Fe 18 Ni balance Cu 1,5