Like it or not, you must choose. 1095 or D2? 8Cr13MoV or AUS-8? H1 or ZDP-189? And those are just a few of the varieties of knife steels, of which there are thousands.
Dialing in on which steel suits your needs best is a confounding business, but few factors are as important to knife function as the choice of steel. Some steels are harder than others, some are easier to sharpen, some are known for holding an edge, and some are more resistant to corrosion. Each attribute typically comes with a tradeoff. A blade that is harder and holds an edge longer, for example, might be prone to chip. Knowing a bit about steel metallurgy will help you pick the right knife, whether you want an inexpensive model or a high-dollar custom blade.
Carbon Steel Vs. Stainless Steel
Basic steel is simply iron and carbon. But over the ages, steel makers learned that a pinch of cobalt or a dash of chromium—or a smidge of more exotic compounds such as vanadium or molybdenum—changes a steel’s character. The least you need to know is that the higher the carbon content, the harder the blade and the better it holds an edge. But too much can make a blade brittle, reducing toughness. Blades with a higher carbon content also rust and corrode more easily. Adding chromium prevents rust but it can soften the steel.
And that brings us to the first big decision: Do you want a carbon-steel blade or a stainless-steel blade? All steels contain carbon. The defining difference between carbon steel and stainless steel is that stainless-steel blades typically contain between 10.5 percent and 16 percent chromium in the alloy.
The Advantages of Carbon Steel
Carbon steels often include various added elements to give the steel specific properties, but chromium is either absent or present in very low amounts. Carbon steel proponents point to its relative ease of sharpening, edge-holding ability, and the fact that carbon steel can be differentially heat treated—with a very hard edge, for example, and a softer, more flexible spine. And for many, the fact that carbon steel stains is a plus. It requires a bit of cleaning and oiling. But like a fine wood gunstock aging and darkening, a blued carbon knife blade wears a story-rich patina.
The Advantages of Stainless Steel
When it comes to stainless steel, let’s be clear: There’s no such thing as truly stainless steel. An alloy that’s absolutely impervious to rust would have to contain so much chromium that it would be useless as a knife. But when chromium is added to a steel alloy and the metal is heat treated, protective chromium oxide turns back crud, making stainless blades easier to care for. Popular inexpensive stainless steels include 440A, 440B, and 440C, and while they’ll polish to a mirror finish, they are very difficult to sharpen to as keen an edge as other steels. If you prefer your blades to be very sharp and shiny and easy to work with, upgrade to better stainless steels such as 154CM, ATS-34, AUS-8, the CPM stainless series, Sandvik 12C27, and VG-10. Or you can buy a Morakniv or Helle knife, and bask in the glow of their proprietary, and very fine, stainless steels.
What the Heck is Super Steel?
Many new high-technology steels are made of powdered, or pelletized, steel. First, a desired alloy is formulated and melted. This molten metal is then processed through a high-pressure air or gas cannon, which atomizes the metal into a fine spray of mist-like droplets. These harden into tiny round powder pellets, with very few impurities. The millions of granules of evenly distributed carbides allow for hair-splitting edge grinds and no weak spots in the blade. Many of these steels, such as CPM 154, ZDP189, M390, and Elmax, pretty much do it all, and knife buffs call them “super steel.” They’re corrosion-resistant, hard, and tough. Naturally, you pay for it.
17 of the Best Knife Steels for Outdoor Blades
Now that you know enough about knife steels to make your own informed decisions, here are a few favorites to consider.
5 Great Carbon Steels
1. 1095 Steel
A very popular and simple alloy that has been around forever. It is used in a great many inexpensive knives, but still furnishes the blades for some very costly knives, too. It’s easy to sharpen and takes a keen edge. Over time, tool steel like 1095 blues with use, acquiring a pleasing character.
2. 0-1 Steel
This steel is favored by the famed knife maker Bo Randall. With a carbon content nearing 1 percent, it’s a hard steel with great edge retention, but it’s less desirable on large blades due to brittleness.
3. D-2 Steel
Containing almost enough chromium to be considered a stainless steel, D2 is rust-resistant (although it will stain), very tough, takes a first-class edge, and holds that edge nearly forever. It’s an awesome knife steel, but it takes care and skill to sharpen.
4. 52100 Steel
A very hard, high-carbon tool steel. Holds an edge well but can be difficult to sharpen. With less chromium than other tool steels, it is prone to rust, but makes a great hunting knife.
5. 5160 Steel
A simple carbon steel with a smidge of chromium for strength, it was considered by the great smith Bill Moran to be the best of the knife steels.
A Dozen Top Stainless Steels
6. AUS-6 and AUS-8 Steel
Japanese versions of 420 stainless steels, with vanadium in the alloy for wear resistance. AUS-6 has .65 percent carbon. AUS-8 has .75 percent carbon. They are inexpensive and widely used.
7. 8Cr13MoV Steel
China-produced steel similar to AUS-8 with slightly more carbon in the alloy. Easy to sharpen, decent edge retention. A great mid-range steel when heat treated properly.
8. Sandvik 12C27 Steel
Very popular Swedish steel that’s a definite upgrade from the 440 series. Manganese in the alloy allows it to sharpen easily and hold an edge well, making it a less-expensive choice with high-performance characteristics.
9. 154 CM Steel
A hard American Crucible steel with 1.05 percent carbon content and added molybdenum. Holds an edge very well. Often used in high-end custom knives and top-shelf manufacturers. Rusts only with difficulty.
10. ATS-34 Steel
Japanese steel with 1.05 percent carbon content, very similar to 154CM. The addition of vanadium gives it a great balance between corrosion resistance and edge-holding ability.
11. VG10 Steel
Japanese steel with better corrosion resistance than 154CM and ATS-34. A fairly hard steel, tough, and relatively easy to sharpen.
12. CPM S30V Steel
Very popular for upper-level knives, the carbon content of 1.45 percent makes for a tough knife with great wear resistance. The “V” denotes the vanadium carbides that boost the steel’s hardness. A great choice for all-around performance.
13. CPM S35VN
An upgrade from S30V steel with the addition of niobium for toughness and ease of sharpening, it’s an affordable top-shelf steel.
14. ZDP-189 Steel
Hitachi powder steel with super-high levels of carbon and chromium for super-high hardness—64-66 HRC. Once sharp, it stays sharp practically forever, which is a good thing, because sharpening this steel is not easy.
15. Elmax Steel
The Swedish firm Uddeholm developed this powder steel that’s very high in both carbon and chromium and combines extreme corrosion resistance with high wear resistance. This means it resists rust stubbornly, and once it takes an edge it keeps it. Pretty close to perfect, it’s hardened to HRC 60-61.
16. M390 Steel
The brainchild of the Bohler-Uddeholm merger, the powdered M390 super steel contains tungsten for wear, corrosion resistance, and edge-retention scores that are off the charts.
17. H-1 Steel
Miracle of alloy miracles: With 1 percent nitrogen in the alloy, this is a steel that will cut shrimp for surf fishing and never rust no matter how long it bangs around, forgotten, in your tacklebox. Great edge-holding ability. Perfect for saltwater environments.