It’s Important to Know the Metal of Your Knife
- But You Should Know About the Experts
- How Much Does the Steel of a Knife Actually Matter
- What’s the Difference Between Carbon and Stainless Steel and Some Stuff in Between
- What is Carbon Steel
- What is Stainless Steel
- What is Tool Steel
- What is Alloy Steel
- What is Powder Steel
- What is Damascus Steel
- What are Steel Standards
- What is Rockwell Hardness
- The Companies that Make the Most Commonly Used Knife Steels
- The Best Knife Steels for Each Job
- Final Thoughts on Choosing a Knife
We need to talk about steel types, and we need to do it simply.
This is not meant to be a comprehensive list and explanation of steels (although it’s gotten longer than I intended). There are a couple of incredibly competent people diligently pushing against the culture of quick, pseudoscientific explanations propagated by people like me that you should check out if you want the real meat of this information.
The problem is those competent people tend to create content specifically for knife makers, and brings a whole truck load of detail that’s hard for the casual knife buyer to get past that to the kernel of information that might actually be useful for them when it comes to the pivotal choice between a sprint run Spyderco Massad Ayoob in Cruwear, or a humble CRKT flipper in D2.
This guide is meant to be a simplified consolidation of information, mostly gleaned from those more competent people to help cut through the noise to reveal a few choice chicken tenders of truth for those regular folks who just want to buy a knife and know every god forsaken thing about it.
But You Should Know About the Experts
You’ll see Larrin Thomas’ name a lot in this article. He’s the man behind Knife Steel Nerds, and honestly you might be more interested in just reading his steel ratings article.
We also follow knife maker Shawn Houston pretty closely. He’s an excellent resource for getting highly detailed advice on sharpening. His YouTube and Instagram feed are the places to go to see some practical application of deep carbide knowledge.
The Troopah Knives Instagram does something called Steel Saturday, where he chooses one steel to write intensively about, which is an excellent way to hear directly from a custom maker’s experience.
And when we want to find out (or remind ourselves) about the composition and characteristics of a specific steel, we usually go to ZKnives for a quick reference.
Now, I just want to clear up one more thing:
How Much Does the Steel of a Knife Actually Matter
A lot, but also not actually that much. Edge geometry has a much larger effect on the performance of a knife, and a good heat treatment (and proper care) can make any modern steel last a lifetime.
Here are the three elements all knife makers are compromising with in every design:
- Edge retention
- Corrosion resistance
While the heat treatment determines the final hardness of a knife, every steel has an upper and lower range of hardness that it performs best at, and some steel compositions might be better suited to thinner grinds than others.
For example, D2 is a fantastic budget steel with excellent edge retention, but it tends to be chippy, so it’s not as tough in thinner grinds as something like Sandvik 12C27, which, in turn, is usually much worse in edge retention.
There are some steels that have a better compromise between toughness and edge retention. It’s not for nothing that CPM S30V took over the knife world in the early 2000s, or that CPM Magnacut is taking it over now in the Neo 20s. But when you hear people talking about how one knife is better than another because of the blade steel, it’s important to take that comparison in with the context the knife is being used in.
For example, talking about how a Shun Classic chef’s knife is better than a Wusthof Ikon chef’s knife because it’s so much harder and has better edge retention completely ignores the different purposes of those two knives: the Shun is a high-performance cutter, the Wusthof is a tough workhorse. One can cut a free-standing tomato in half, while the other can spatchcock a turkey.
In that same vein, it’s great that so many knife makers are embracing Magnacut, but older steels like AEB-L and 154CM have served the community well for many years, and no matter how much of a drop in performance you think you’re getting with one of them than Magnacut, the price probably dropped far more than the performance.
What’s the Difference Between Carbon and Stainless Steel and Some Stuff in Between
First someone baked some carbon into iron and noticed it made that iron significantly harder. A few hundred years later, some other curious fellow noticed that if you added chromium to that mix the steel didn’t rust as easily. There were some other wacky experimentations with elements like vanadium and tungsten that resulted in tool steels and alloy steels. We’ll try to take each of these one at a time, in quick, simple terms.
Or you could just read Dr. Thomas’ article Carbon Steel vs. Stainless Steel, which doesn’t take quite the same pains at being simple, but is significantly more comprehensive. Plus it has the benefit of a doctor’s authority over that of a moderately well-read stranger on the internet.
Or you could read Troopah Knive’s steel page, which is much simpler and has some very pleasant graphs. It’s almost too simple for extended curiosity though, and I’m trying hard to be the middle ground here.
What is Carbon Steel
Carbon steel is essentially your bare bones composition. It’s mostly iron and carbon with little to no alloying elements intentionally added into the mix. Common steels in this category are 1095, 1084, and 1075. Those last two numbers of those three indicate the carbon content by percentage, so 1095 has 0.95% carbon by weight, which is quite a bit in the larger context.
It’s pretty common to see these steels in budget survival knives because they’re easy to work with, and often easier for the end user to sharpen, but don’t let the fact that a knife features 1095 make you think it only belongs exclusively in a budget category. Some knife makers are absolute artists with carbon steels, and there are a couple of production-level manufacturers like Ka Bar that put out some fantastically high quality blades in 1095.
The term has become effectively synonymous with “high carbon steel”, although it’s fair to make an argument that “high carbon” could just mean a steel prominently featuring carbon in its make up, but there could also be a bunch of other stuff in there that would make it an alloy steel, which we’ll define a little later.
What is Stainless Steel
It’s easier to say that stainless steel is just steel that doesn’t rust easily. The “official” definition is that stainless steel one with a composition of at least 12% chromium, but that definition is getting more complicated as steel technology advances, because there are now steels (like Magnacut) that exhibit stainless properties without reaching that 12% chromium mark.
So you’ll get highly corrosion resistant steels like LC200N (15% chromium) and H2 steel (somewhere around 13% chromium) which have been used prominently in Spyderco’s Salt line because of their high stainless properties. But they dropped both those steels for Magnacut which only has about 10% chromium.
Meanwhile, D2 typically hits that 12% mark, but it’s not fully stainless because because the high carbon content ties up a lot of chromium into carbides within the steel rather than allowing it to form a protective layer around the blade (you can read more about this fun battle of chemical reactions in Larrin Thomas’ article How Much More Chromium Does D2 Need to be Stainless).
So it’s easier to define these steels by how they behave. Put some water on a blade and leave it out for a couple of days. If it doesn’t rust, it seems fair to call that stainless.
It’s also important to keep in mind that the stainless characteristic is on a sliding scale partially changed by heat treatment and the knife finish. So the name of the steel alone doesn’t always provide a clear idea of how corrosion resistant it will be. You can read up more on that here.
What is Tool Steel
Any steel used in tooling is a tool steel, which includes die steels (like D2) which are used to cut other metals and materials.
Since this category is defined more by use, the steels used within it can have a lot of spill over into other categories. Obviously they have to be hard, though, so carbon and other hardening elements like silicon and molybdenum are pretty common in them.
Other tool steels are W2, A2, O1 and 3V, all of which you’ll see in a range of outdoor knives by especially skilled companies like Battle Horse and LT Wright.
What is Alloy Steel
An alloy steel is any steel with a total of 1 – 50% alloying elements in its composition. So something like 1095 is close to being on that list but not quite. Those elements can include silicon, vanadium, and molybdenum. Chromium is also in that list of elements, but it’s worth making a distinction between stainless and alloy steels, because not every alloy composition results in stainless properties.
I know some people read that in a quietly growing rage at what is surely the equivalent of taking the alphabet one letter at a time for them, but it’s important to emphasize this for the drooling common folk (like myself): Not all alloy steels are stainless.
52100 is probably the most widely used steel in this category (at least for custom makers). It has some properties that make it incredibly easy to work with and refine, but it’s far from having stainless properties. 5160 is similar, but can’t quite reach as high of a hardness.
There’s also something that Larrin Thomas calls “high alloy steel”, which can be really cool stuff, but creates some complications for manufacturers, which is what led to this next type of steel.
What is Powder Steel
Basically it’s when a steel is sprayed into a rough sand form before being turned into an ingot.
You can read about the process and benefits of this method in the article “What is Powder Metallurgy” by Larrin Thomas, but the short version is that steels with a large amount of alloying elements make it increasingly difficult to work through conventional ingot methods because they raise the temperature at which steels can achieve optimum hardness (painting in broad strokes here).
Powder metallurgy is a process that turns that high alloy steel into hundreds of tiny ingots (the powder), then the powder is pressed into a canister to form a workable ingot with a more uniform structure with smaller carbides.
This process allows for some pretty wild alloy compositions to enter into the knife making community. Something like S30V, which has a widely varied cocktail of alloying elements that wouldn’t normally mix well without incredibly high temperatures, becomes significantly more workable because each grain in the powder is its own little pre-mixed ingot.
What is Damascus Steel
We answer this question in painstaking (but still somehow insufficient) detail in our Idiot’s Guide to Damascus Steel, but a simple summary is that, in modern terms, Damascus steel is a pattern welded steel where two or more steels have been forged together to create a pattern.
The typical mix for most custom makers is 1084 and 15n20 (a high-nickel steel), but there are almost as many kinds of Damascus steels as there are people making Damascus steel knives, which makes it very difficult to talk generally about the quality or characteristics of Damascus. I feel comfortable saying that the steel itself doesn’t typically make a knife better than any kind of monosteel. Or if it does, the improvement would be hard to discern from anything that can be attributed to the skill of the person making the knife in the first place.
The gold standard comes from Damasteel, though. Not only are they creating incredibly high quality bars that custom makers seem to love working with, but they provide a lot of information freely on how to work with each of their steels.
What are Steel Standards
There are several different organizations across the world that grade steels based on use, composition, and strength. Their designations basically make things more fluid for scientists and engineers across several different industries by maintaining a standardized language.
In Germany there’s DIN, in the USA there’s AISI, and Japan has JSI.
I don’t think anyone reading this blog really needs to know this, but it can be interesting if you really want to get into the weeds. Zknives has a good comprehensive list of the various steel standards around the world. You can look into it yourself if this kind of thing gets you going.
What is Rockwell Hardness
The Rockwell Hardness expresses a certain kind of metal’s ability to hold up to deformation.
This is determined with a machine that presses a ball into a material at variable pressures until it creates an indent in the material. The Rockwell hardness is based on the depth of the indentation created by certain loads.
There are several different kinds of scales of Rockwell Hardness. Knife steels are tested on the C scale for reasons I won’t get into, because I don’t totally understand them. But I can say that this is why you see the abbreviations RC or HRC show up in knife listings and reviews. The important thing most consumers need to know is that the higher the number behind HRC the harder the knife, which isn’t to say the knife is better. As always, you should place more value on the intent of the knife and the skill of the maker.
But we’ll feed into the somewhat arbitrary need to designate things based on simple numbers, so here’s a quick guide to the hardness ranges that are generally standard for different kinds of knives.
Average Rockwell Hardness by Knife Type
|Knife Type||Typical Rockwell Hardness|
|Outdoor, budget EDC, tactical||54 – 58 HRC|
|Mid-range to high-end EDC and outdoor||58 – 62 HRC|
|Western kitchen cutlery||58 – 60 HRC|
|Japanese kitchen cutlery||60 – 64 HRC|
The Companies that Make the Most Commonly Used Knife Steels
Steels are being judged more often by their maker these days, so it’s worth listing a few of companies responsible for our favorite (or least favorite) steels. It can be complicated to talk about what companies make what steel, because some are proprietary, like AEB-L, and some seem to be made by everyone, like 440C. There’s also 1095, which is a widespread steel standard, but then there’s 1095 Cro-Van, developed by Sharon Steel, which shut down in 1992, and now I’m not really sure who makes it or even owns the name.
So ignoring complications like that, I’ve tried to list the knife steels most commonly associated with each company. Of course, Larrin Thomas already wrote an article about steel manufacturers and suppliers, so I won’t go into much detail. But I will lay it out in a table that’s a little easier to reference quickly:
|Company (Country)||Steels Used in Knives|
|Ahonest Chankjiang (China)||420J, 8Cr14MoV, 9Cr18MoV,|
|Aichi Steel (Japan)||AUS-8, AUS-10|
|Bohler-Uddeholm (Austria)||Elmax, Sleipner, M390, N690, AEB-L, K390|
|Carpenter Technology (USA)||52100, All “CTS-” steels, Maxamet|
|Crucible Industries (USA)||Most “CPM-” steels, 154CM|
|Damasteel (Sweden)||Often listed by pattern name or simply as “Damasteel”|
|Hitachi (Japan)||ZDP-189, SG2, SLD, White (#1 and 2), Blue (#1, 2, and Super)|
|Kobelco Steel (Japan)||R2|
|Latrobe (USA)||420HC (also called Tru-Sharp)|
|Myodo Metal Co (Japan)||H1, CPM 20CV|
|New Jersey Steel Baron (USA)||Nitro-V|
|Sandvik Group (Sweden)||12C27, 13C26, 14C28N|
|Takefu Special Steel Co (Japan)||VG-10, VG-MAX|
|Thyssenkrupp Steel (Germany)||80CrV2, 4116|
You might have noticed a few prominent steels missing from that table, so before you get your pitchforks out, here are some popular knife steels that are considered standard. They’re incredibly common and made by factories the world over:
|Standard Carbon Steels||Standard Stainless Steels|
|O1||440 (A, B, and C)|
|SK85 (previously SK5)|
The Best Knife Steels for Each Job
Hold on. We don’t actually mean “best”. Just… good enough to end up in that field a lot. There’s a reason you see Sandvik 14C28N show up in so many bushcraft knives, and that 1.4116 steel has been used in German kitchen cutlery for decades.
We don’t want to be the arbiters of steel quality here, we’re just making tables based on what we’ve used and what we see the knife industry as a whole doing. As such, you will probably see a few steels you think you hate show up in here. Feel free to rage in the comments below.
I’ve also tried to keep repetition out of these tables, but steels like CPM-S35VN, D2, Magnacut, 1095, and basically every Sandvik steel show up in every category of knife in every price range.
Otherwise, you should check out ZKnives for a more extensive explanation of all these steels, and a breakdown of their compositions. Better yet, download his app.
Steels for Kitchen Cutlery
The status quo in this category is that Western chef’s knives are tough and heavy, while Japanese chef’s knives are hard and thin. There’s a whole thing with carbon steels in traditional Japanese knives that this table will barely scratch at, but, as always, my hope is that you’ll find more detailed sources if any of this piques your interest.
|Steel Name||Common Properties|
|VG-10||Now considered a good mid-range steel. It holds a decent edge and has good corrosion resistance, but can be chippy on thin blades.|
|VG-MAX||Basically a slightly harder version of VG-10. It has better edge retention. You’ll see it in Shun’s higher-end knives.|
|White (Shirogami)||This is about as pure of a carbon steel as you can get. Takes a very thin edge that is exceptionally easy to maintain. There are two version (#1 and #2) with varying amounts of carbon.|
|Blue (Aogami)||Similar to White steels, but with a little bit of chromium and tungsten added so it’s a little more stainless (still forms patina easily, though). Also comes in #1 and 2 versions with different levels of carbon.|
|Blue Super||The hardest of the blue steels, but also the least tough.|
|1.4116 (X50CrMoV15)||Standard German cutlery steel. Low-ish carbon, high chromium. This is phenomenally tough stuff in the right hands.|
|14C28N||A good all-around steel generally seen in western-style and outdoor-centric cutlery. This is a good stainless steel with a fine carbide structure, and a working hardness up to 62 HRC.|
|RWL34||Typically seen in high-end production knives, this is actually a Damasteel creation based on 154CM, but using powder metallurgy. Exceptionally hard stuff with a very stable structure and good edge holding.|
|ZDP-189||A powder steel with an enormous amount of carbon, which makes this a very hard steel. There’s also plenty of chromium in there to make it stainless.|
|R2 (SG2)||A hard powder steel with a good mix of corrosion resistance, wear resistance, and edge stability. Very often seen on high-priced kitchen knives.|
|Ceramic||Not a steel, but there are ceramic knives out there, especially in the kitchen. These will be very frail, but have fantastic wear resistance so long as the manufacturer got the edge geometry right.|
Steels for Budget Knives
I’m calling a budget knife anything under $150-ish. I know that still sounds high to some of you, so I’ll direct you to our Best Hard Use Folders article where we knock that down to under $50.
|Steel Name||Common Properties|
|AUS-8||Good corrosion resistance and toughness, but not so great for holding an edge. Similar to 8Cr14MoV and 440B.|
|D2||A high alloy steel with good hardness for the price. It can get chippy on thinner blades, though, and it really likes a toothy edge. Also moderately prone to rust.|
|8Cr13MoV||Usually a tough steel with good corrosion resistance. These knives don’t usually hold a good edge, but it can turn out a good beater knife in the right hands.|
|420HC||A pretty simple stainless steel with good corrosion resistance and okay edge holding. Turns into something special from companies like Buck, though.|
|154CM||The much-loved steel of Bob Loveless. This was the king of the knife world back in the day. It still has some decent hardness and okay toughness. Works great in pretty much all categories, though.|
|Nitro-V||A modification of a couple Sandvik steels with exceptionally good edge stability. Good toughness, and decent edge holding, but takes an excellent edge either way.|
|AUS-10||A good mid-range steel capable of decent hardness and good edge retention. Can become pretty tough with the right treatment.|
|N690||A cobalt steel with very high corrosion resistance and tensile strength. Better edge holding than most other budget steels except for 154CM and AUS-10.|
|AR-RPM9||Possibly the first budget powder steel in existence. This has exceptional edge stability, making it good for a variety of edge types and remains easy to maintain. Also has excellent corrosion resistance.|
Steels for Mid-Range to High-End Knives
Basically knives from $200 and beyond. Originally I was going to have mid-range and high-end separate, but both of those categories had a lot of the same steels, so here we are.
|Steel Name||Common Properties|
|CPM-S35V||A powder steel with good toughness and excellent corrosion resistance and edge retention. It’s considered the slightly tougher version of S30V.|
|M390||A fine-grained steel with very good edge retention and stability down to a certain thinness.|
|CPM 20CV||Very good edge retention and corrosion resistance. Behaves similarly to M390.|
|CPM-154||The powder version of 154CM is significantly more stable with better edge retention.|
|Elmax||A very high carbon stainless steel that is famously (or infamously) good at holding an edge.|
|CTS XHP||A bit like 440C but holds a much better edge. Corrosion resistance and hardness are its big focuses.|
|AEB-L||A simple steel with good toughness, and is very agreeable to shaping for a stainless steel. Very popular with custom makers.|
|CPM-Magnacut||A powder steel that is currently considered to have the best compromise between toughness and edge retention. Also reportedly has very good corrosion resistance despite low chromium content.|
Steels for Bushcraft and Survival Knives
I’ve left out some budget and mid-range steels from this list, but it’s worth knowing that AEB-L, 14C28N, and AR-RPM9 are also very popular in this category.
|Steel Name||Common Properties|
|1075||A simple carbon steel with high toughness and moderate edge holding. It’s very easy to shape and forge.|
|1084||Like 1075, but it’s a bit harder. Still in the lower range for wear resistance of what’s considered standard these days, unless treated and ground very well.|
|1095||The carbon standard. This has a much higher working hardness than the previous two, but toughness and shock absorption are still its big draws.|
|1095 Cro-Van||A little extra dose of a couple alloying elements make this the harder and tougher version of 1095.|
|A2||A phenomenally tough, air-hardening steel.|
|O1||Not as tough as A2, but apparently has a higher working hardness. Another one that’s popular with custom makers in the forge.|
|Sleipner||Could be called the European D2, but it’s been modified slightly to be a bit tougher.|
|CPM-3V||A fantastically tough powder tool steel. It also has a high working hardness, and exhibits surprisingly good stainless properties (but not enough to be stainless)|
|Lam.Cos||This laminated version of Takefu’s CoS steel has excellent edge holding, and the 420J lamination makes the corrosion resistance pretty good too. Falkniven loves this stuff.|
Final Thoughts on Choosing a Knife
If this topic doesn’t excite you, and you’re just sitting here overwhelmed by the barrage of numbers, letters, and carbon percentages, don’t worry. You don’t have to know the composition of a knife to know it’s good.
Most companies are pretty resolute about using good steel, and if you’re paying over $20 it’s almost certain the steel is at least decent. But if you’re looking at a $5 dollar knife and wondering if it might still be useful, or looking at a $70 knife and wondering what’s weighing that price tag down, the steel is a good place to start looking.