M390 vs. S90V vs. 154CM: Three Steels, Compared Honestly

01 What is powder metallurgy steel?

Powder metallurgy steel is made by atomising a molten alloy into fine droplets and sintering the powder under enormous pressure, rather than melting and casting it. The result is a grain structure far finer and more uniform, with small, evenly spread carbides instead of the uneven clumps that casting leaves behind.

M390 and S90V are powder steels. That process is why they can carry extreme alloy loads — vanadium contents that would make a cast steel brittle and unworkable — and still take a keen, stable edge. 154CM is the conventionally cast benchmark in this trio, and it earns its place on different terms.

02 What is M390 steel?

M390 (and its near-twins 20CV and CTS-204P) is a Bohler powder stainless built around roughly 20% chromium and 4% vanadium. Its reputation is earned: edge retention near the top of the stainless class, corrosion resistance that shrugs at sweat and rain, and enough toughness for real daily work rather than display-case life.

The cost arrives at the sharpening bench. Those vanadium carbides resist the stone almost as well as they resist cardboard. M390 wants diamond abrasives and patience — and it rewards them with an edge you sharpen rarely. Choose M390 if you want the best all-round performance modern stainless can offer and you accept slower, more deliberate maintenance.

03 What is S90V steel?

S90V is a Crucible powder stainless carrying about 9% vanadium, which forms a dense population of very hard carbides. That gives edge retention outlasting nearly everything else you can pocket — weeks of cardboard, rope, and packaging before the edge asks for attention — at the cost of toughness and easy sharpening.

The trade-offs are real. Sharpening S90V is a project, not a touch-up — those vanadium carbides are harder than common stone abrasives, so it wants diamond or CBN — and its corrosion resistance sits a step below M390. Choose S90V when edge life is the priority above all — heavy daily cutting, long trips away from the bench — and you are willing to pay for it in sharpening time.

04 What is 154CM steel?

154CM predates the powder era — a cast high-carbon stainless, the American evolution of ATS-34's family, with a decades-long record in hard-use knives. It holds an edge respectably rather than spectacularly, resists rust competently, and is meaningfully tougher than its reputation suggests.

Its superpower is maintenance: 154CM sharpens quickly on ordinary stones, takes a screaming edge with minimal ceremony, and forgives a owner who sharpens on a budget of time. A knife you can restore to razor in five minutes is a knife that is always sharp. Choose 154CM when you value easy upkeep, field sharpenability, and honest pricing over spec-sheet glory.

05 The verdict, by carrier

There is no winner — there is only fit. Be honest about how you actually use and maintain a knife, and the choice makes itself:

• ◆ M390 — for the carrier who wants elite all-round performance, cuts daily, and sharpens occasionally but properly.
• ◆ S90V — for the heavy cutter who measures a knife in weeks-between-sharpenings and treats edges as consumables to be rationed.
• ◆ 154CM — for the pragmatist who would rather touch up an edge in minutes than schedule a sharpening session, and who values toughness and price honesty.

06 A note on heat treatment

One caveat worth engraving: the steel name is the recipe, but heat treatment is the cooking. The same M390 can perform admirably or disappointingly depending on how the maker hardened and tempered it. This is why the vault states HRC targets alongside steel names — and why we stock makers whose heat treatment has proven itself on the stone, not just in the brochure.

Sources & Further Reading

• ◆ Knife Steel Nerds — M390 Steel: History and Properties (and 20CV and 204P)
• ◆ Knife Steel Nerds — S90V and S125V Knife Steel: History, Properties, and How to Heat Treat
• ◆ Knife Steel Nerds — Testing the Edge Retention of 48 Knife Steels (CATRA data)

Frequently Asked Questions

Questions from the Counter

Is M390 better than S90V?

Different, not strictly better. S90V holds an edge longer thanks to its high vanadium carbide content, and independent CATRA testing has found it matches or beats M390 on toughness as well. M390 answers with better corrosion resistance and meaningfully easier sharpening. Most carriers are better served by M390's balance; heavy abrasive users benefit from S90V's extreme edge life.

Is 154CM still a good knife steel?

Yes. 154CM remains a proven, tough, corrosion-resistant stainless that sharpens quickly on ordinary stones. It gives up raw edge retention to powder steels like M390, but its ease of maintenance and honest price keep it relevant for everyday and outdoor use.

How often does M390 need sharpening?

Under typical EDC use — opening packages, breaking down cardboard, food prep — an M390 edge commonly stays working-sharp for weeks to months. When it finally dulls, plan on diamond abrasives and a longer session than simpler steels require.

Do powder steels rust?

M390 and S90V are both highly corrosion-resistant stainless steels, but "stainless" is not "stain-proof." Salt water, acidic foods, and prolonged wet storage can still mark them. Rinse, dry, and an occasional drop of pivot oil keeps either steel spotless.

From the Page to the Palm

Reading about steel is one thing. Holding it is the other.

Every claim in this guide is backed by a piece on the shelf — titanium edc steel, named and priced plainly in CAD.

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