INSIGHT

Knife Steel Types and Hardness Comparison for OEM Knife Programs

Most brands that send us a drawing already have a steel written on it. Sometimes it's the right one. Sometimes it was copied from a competitor's spec sheet, and it doesn't match the price the knife has to sell at or what the knife will be used for.

This is a comparison of six steels that cover most OEM knife projects, from entry-priced folders to powder steel flagships. The compositions and hardness figures come from mill datasheets and published test work, listed at the end. They are not our own lab numbers.

The comparison table

Steel Type Carbon Chromium Hardness (HRC)
8Cr13MoV Stainless 0.80% 13% 58–60 typical
9Cr18MoV Stainless 0.85–0.95% 17–18% 58–60 typical
14C28N Stainless, nitrogen alloyed 0.62% 14% 55–62
D2 Tool steel, not stainless 1.42% 11.5% 60–62
CPM S35VN Powder stainless 1.40% 14% 58–61
CPM S90V Powder stainless 2.3% 14% 56–59

Read the hardness column as a range the steel can reach, not a number you automatically get. Where a blade lands inside that range is decided in heat treatment, and that is the factory's work, not the mill's.

8Cr13MoV and 9Cr18MoV

8Cr13MoV is the default steel for entry-priced knives made in China. It has the same composition as the Japanese AUS-8. Larrin Thomas at Knife Steel Nerds tested it in 2024 and found it tougher than 440C, VG-10 and 154CM, with edge retention a little below them. His summary was "a good low cost steel".

9Cr18MoV carries more carbon and a good deal more chromium, 17–18% against 13%. On paper that buys better corrosion resistance and edge holding while staying in the budget tier.

Neither steel will impress a knife enthusiast reading the spec. Both are honest choices for a knife that has to retail at a low price and get used.

14C28N

14C28N is made by Alleima in Sweden (formerly Sandvik) and was developed for knife blades. It has less carbon than the others in the table, plus a small nitrogen addition. Alleima recommends 55–62 HRC for knives and describes its edge stability, meaning resistance to micro-chipping and rolling, as good. In the Knife Steel Nerds test, 14C28N was significantly tougher than 8Cr13MoV.

For a mid-priced folding knife we think it is the safer spec than D2. The hardness is similar and it is properly stainless.

D2

D2 is a tool steel. It holds an edge well because the structure is full of hard chromium carbides, and it is heat treated to 60–62 HRC. Buyers know the name, which is a large part of why it shows up on so many spec sheets.

The catch is corrosion. At 11.5% chromium, with much of that locked up in carbides, D2 is not stainless. In Crucible's corrosion comparison it lost material roughly nine times faster than 440C in boiling acetic acid (the datasheet calls this a qualitative comparison). On a coated EDC blade that rarely matters. On a fishing knife, or anything sold into humid coastal markets, it's the wrong steel.

Powder steels: S35VN and S90V

Powder metallurgy steels are atomised and consolidated instead of cast as an ingot, which gives a much finer and more even carbide structure. That allows far more carbon and vanadium than a conventional steel could carry.

CPM S35VN is the all-rounder: 3% vanadium, a little niobium, and an aim hardness of 58–61 HRC. CPM S90V has 9% vanadium. In Crucible's wear test it scored about ten times higher than both D2 and 440C, at a lower aim hardness of 56–59 HRC. S90V is a good reminder that hardness alone says little about how long an edge lasts.

These steels cost more as raw material, and they cost more again in the factory. They grind slowly and need tighter heat treatment control. A knife in S90V is not a knife in 8Cr13MoV with a different bar of steel in it. It is a different production plan.

Hardness is set in heat treatment

Two details from the Alleima datasheet for 14C28N show how much depends on the factory. Deep freezing after the quench adds about 1–2 HRC. Tempering above 450°C makes the steel brittle and costs it corrosion resistance. Every steel in the table has its own version of this.

So when you compare quotes, don't stop at the steel grade. (We wrote up the rest of what to ask in Questions to Ask a Knife OEM Factory.) Ask for the hardness target and tolerance in writing, for example 58–60 HRC, and ask how it is tested: on a coupon or on the blade, and how many pieces per batch.

How we'd narrow it down

Start from the retail price and the use, then pick the steel. For an entry-priced knife, 8Cr13MoV or 9Cr18MoV. For a mid-priced folder or a fixed blade that will see water, 14C28N. D2 if your customers ask for it by name and the blade is coated. A powder steel when the knife is priced to carry the extra grinding and heat treatment cost.

On our own lines, the steels we list for knife programs include D2, 14C28N, AEB-L and Nitro-V, and powder steels such as CPM S35VN, CPM S90V and Böhler M390. Heat treatment is done in-house at both factories, with cryogenic treatment and hardness testing to the program specification.

If you're not sure which steel fits, send us the drawing with your target retail price and where the knife will be sold. We'll recommend a steel and tell you why.

Sources