The type of steel used to make a knife blade is critical in determining its quality, which is why reviews for the best steel for knives are useful. But it should be mentioned that “type of steel” is not a solitary factor. A knife made with a great steel can still turn out poorly if the process used to shape it is bad. Similarly, a lower-grade steel can perform quite well if a lot of thought goes into its creation.
That having been said, different steels do have different attributes that make some more or less suitable for blade-making. Here we review several of those most suited for this sort of production.
One of Crucible Industries’ bestsellers, this steel is 9% vanadium, 14% chromium, 2.3% carbon and 1% molybdenum. The combination results in a steel perfect for cutting implements as it boasts near-unparalleled edge-holding and resistance to wear. This steel blade will cost you about $250.
- Excellent edge-retention
- Excellent wear-resistance
- Very good hardness
- Very difficult to machine
It should come as very little surprise that the CPM steels make their way to this list. CPM steels are exclusively manufactured by Crucible Industries and boast generally superior traits compared to their non-CPM counterparts.
S90V is no exception: a high-carbon and high-vanadium steel, it has exceptional wear-resistance and edge retention. In fact, in most roundups of favored steels for blade-making, it will be at the top of the list for both those traits. It has great hardness too and above-average resistance to corrosion.
The only problem is that there’s so much vanadium in it that it can be a pain to machine and grind. This significantly raises the cost of blades produced with it, which is why it’s not a common steel for mass-produced knives.
Also known as the semi-stainless steel, D2 gets this moniker from the fact that it just misses the required amount of chromium to qualify as a “stainless steel”. A high-carbon steel, it can hold an edge nicely because of its hardness. This steel will run around $60.
- Very hard and good at holding an edge
- Common among knife makers
- Decent rust resistance (nearly at the stainless steel level) for its group
- Very difficult to grind to an edge or sharpen
D2 is commonly used in producing industrial tools for cutting, but it can actually serve as a good knife steel as well. It’s fairly easy to get hold of and also has a lot of good traits such as above-average edge-retention, superb hardness (you will usually find it among the top 5 for roundups), and nice rust-resistance because of its high levels of chromium. It’s not an easy steel to sharpen, though, and it takes a lot of practice for a knife maker to learn how to impart a fine edge to a D2 blade. It does look pretty good when highly polished, though, since it can have such a nice shine.
M4 gets its name from the high amount of molybdenum in it: it has 5.25% molybdenum, 4% chromium, 4% vanadium, 5.5% tungsten, 1.4% carbon, and small amounts of manganese, silicon and sulfur. This exotic chemistry yields a high-performance steel with excellently balanced characteristics and will be around $150.
- Superb for cutting
- Great toughness
- Very wear-resistant
- Rather low resistance to corrosion
CPM M4 is one of the “big steels” when it comes to crafting cutting implements. It takes an edge beautifully if you know how to handle it and is significantly easier to sharpen than its higher-vanadium-content sibling (the CPM S90V). It can also hold an edge fantastically owing to its toughness. The only problem is that as far as premium knife steels go, it won’t win any awards in a corrosion-resistance contest. That’s because it doesn’t have enough chromium to make it stainless. It’s not like it’s all that prone to rusting, though: with proper care it shouldn’t ever show a stain.
The third CPM steel on the list, S30V is a martensitic steel with a lot of chromium (14%). It also has 4% vanadium for wear resistance, as well as 2% molybdenum and 1.45% carbon for grinding. This one can be purchased for just under $100.
- Good toughness makes it suitable for lower edge angles on blades
- Excellent balance of attributes
- Widely used, so a lot of premium cutlery can be bought that uses it
- Being a CPM steel, it can still be expensive
S30V is one of the most popular knife steels—that’s to be expected when it was engineered specifically for knife creation. It has great toughness, wear-resistance, edge-retention, and very good corrosion-resistance. It won’t win the top award for any of those criteria, but it does stay high enough in the ranks to make it an exceptional all-rounder. In fact, it’s usually ranked above-average in all the criteria for knife steel evaluation. So while it’s not a stellar performer in the sense of blowing away all of the competition, it is a nice steel to choose if you’re unsure about which characteristics to choose for your knife.
The steel you want should be decided by the use you expect to get out of your knife. People who work in more acidic or saltwater environments should aim for the higher-chromium stainless steels like CPM S90V or CPM S30V, for example, while those who want to focus more on having an unbeatable edge should go for ones like the M4. At the end of the day, the steel you pick needs to be the one that serves you best. So even if someone claims one steel is better than another, you need to contextualize their assertion by asking for details.