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CPM MagnaCut

CPM MagnaCut Knives: The Stainless Steel That Ends the Toughness vs. Edge Retention Argument

CPM MagnaCut is the first powder metallurgy stainless knife steel designed without chromium carbides — the engineering decision that lets it hit exceptional toughness numbers while still outperforming M390 and CPM-S35VN on edge retention. Designed by Dr. Larrin Thomas at Crucible Industries and debuted in 2021, it is now the benchmark every new stainless steel is measured against.

At Knifeworks, you are buying from an authorized dealer: every CPM MagnaCut knife on this page ships with full manufacturer warranty coverage — Benchmade LifeSharp (free lifetime sharpening and mechanical repair), Spyderco's manufacturer warranty, and Zero Tolerance's limited lifetime warranty. No gray-market sourcing, no voided warranties.

Every knife here spans the full CPM MagnaCut production range — from Benchmade and Spyderco folders with Liner Locks and Compression Locks to Zero Tolerance titanium-frame flippers. The steel holds an acute edge longer than CPM-S35VN without the brittleness risk, resists corrosion better than M390, and toughens up with the non-stainless tool steels. It is the closest thing to a do-everything blade steel the industry has ever produced.

Why CPM MagnaCut performs differently than other stainless steelsPrevious stainless PM steels relied on chromium carbides for wear resistance — the same carbides that reduce toughness and can chip at acute edge angles. CPM MagnaCut uses niobium carbides and vanadium carbides instead, which are harder and smaller. The result: better edge retention at thinner geometry, tougher on impact, and cleaner corrosion resistance because all available chromium goes to the matrix rather than tying up in carbides.

Call 888-225-9775 — we carry CPM MagnaCut knives daily and can help you choose the right model.

Steel type
PM Stainless
Designed by
Dr. Larrin Thomas
Typical hardness
61–65 HRC
Toughness
Exceptional
Corrosion resist.
Excellent
Produced by
Crucible Industries

CPM MagnaCut Steel: Frequently Asked Questions

What is CPM MagnaCut steel and why is it so popular?

CPM MagnaCut is a powder metallurgy stainless knife steel developed by Dr. Larrin Thomas and produced by Crucible Industries, first released in 2021. It is the first stainless PM steel designed without chromium carbides — a fundamental change that lets it achieve toughness comparable to non-stainless tool steels while delivering edge retention well above CPM-S35VN and corrosion resistance that surpasses M390.

Before CPM MagnaCut, buying a high-performance stainless knife steel meant choosing between toughness and edge retention. CPM MagnaCut removes that tradeoff. It uses niobium and vanadium carbides rather than chromium carbides, which keeps all available chromium in the steel matrix where it does corrosion resistance work. The result is a steel that does not have to compromise.

How does CPM MagnaCut compare to CPM-S35VN?

CPM MagnaCut outperforms CPM-S35VN on every measurable axis — edge retention, toughness, and corrosion resistance — while being comparable in ease of sharpening. For everyday carry, CPM MagnaCut holds a working edge roughly 30–50% longer than CPM-S35VN at the same hardness. On toughness, CPM MagnaCut at 64 HRC is tougher than CPM-S35VN at 60 HRC. Corrosion resistance is also superior due to the chromium carbide-free matrix.

CPM-S35VN is still an excellent blade steel and many top knives use it well. But CPM MagnaCut is the clear upgrade, which is why Benchmade, Spyderco, Zero Tolerance, and other major brands have moved to it for flagship models.

How does CPM MagnaCut compare to M390 and 20CV?

M390 and 20CV (which are near-identical steels made by different mills) have long been considered the edge retention benchmark for stainless knife steels. CPM MagnaCut matches or exceeds both on edge retention at the same hardness, and dramatically outperforms both on toughness. M390 at 62 HRC is more brittle than CPM MagnaCut at 64 HRC — meaningful for anyone who tasks a knife hard or uses thin geometry.

Corrosion resistance is where CPM MagnaCut wins clearly: M390 and 20CV rely heavily on chromium carbides, which reduce the free chromium available for corrosion protection. CPM MagnaCut keeps all chromium in the matrix, so it tests out with better salt spray and acid resistance despite similar or lower chromium content on paper.

Is CPM MagnaCut hard to sharpen?

CPM MagnaCut is more difficult to sharpen than mid-grade stainless steels like 154CM or CPM-S30V, but it is significantly easier than M390, 20CV, or Elmax. The lack of large chromium carbides means the edge does not feel as "grabby" on a whetstone or ceramic rod, and many sharpeners report it refines more predictably than comparable-hardness steels.

For field touch-ups, a ceramic rod or diamond card works well. For full re-profiling, a diamond stone or CBN wheel is recommended at 61+ HRC. If you sharpen your own knives, CPM MagnaCut lands in the "manageable with quality abrasives" category — not a beginner steel, but not punishing either.

What brands make knives in CPM MagnaCut?

Benchmade, Spyderco, Zero Tolerance, Civivi, WE Knife, and Koenig are among the production and semi-production brands that have released CPM MagnaCut models. Knifeworks carries authorized stock across Benchmade, Spyderco, and Zero Tolerance — all with full manufacturer warranty coverage.

BrandNotable CPM MagnaCut ModelsWarranty
BenchmadeBugout, 940, 535LifeSharp — free lifetime sharpening & repair
SpydercoPara 3, Military, PM2Manufacturer limited warranty
Zero Tolerance0308, 0562, 0990ZT limited lifetime warranty
What hardness is CPM MagnaCut typically run at?

Most production knives run CPM MagnaCut in the 61–65 HRC range. Benchmade typically specifies 62–63 HRC. Spyderco and Zero Tolerance generally target 62–64 HRC depending on the model. Custom makers have pushed as high as 65–66 HRC where toughness demands allow.

One of CPM MagnaCut's advantages is that it retains usable toughness at hardness levels that would make other steels brittle. Running it at 64 HRC gives better edge retention than CPM-S35VN at 61 HRC — with more toughness, not less.

Does CPM MagnaCut rust or stain easily?

CPM MagnaCut has excellent corrosion resistance — better than M390, 20CV, CPM-S35VN, and CPM-S30V in laboratory salt spray testing. Because it contains no chromium carbides, all chromium is available in the steel matrix for corrosion protection. In real-world carry, CPM MagnaCut handles sweat, humidity, food acids, and light saltwater exposure without staining or pitting under normal use.

Like all knife steels, it is not indestructible. Wipe the blade after saltwater exposure, keep the pivot area dry, and the steel will stay clean through years of hard carry.

Which CPM MagnaCut knife should I buy at Knifeworks?

The right CPM MagnaCut knife depends on your carry size preference and how you use the blade. For sub-3-inch EDC, the Benchmade Bugout in CPM MagnaCut is an exceptional choice — ultralight at 1.85 oz, drop point geometry, and LifeSharp warranty coverage. For a full 3.4-inch workhorse, the Spyderco Para 3 or Paramilitary 2 in CPM MagnaCut deliver Compression Lock strength with one of the best production blade steels available.

If you want a titanium-frame flipper with premium fit and finish, Zero Tolerance CPM MagnaCut models pair the steel with KVT ball-bearing pivots and precision USA manufacturing. Call 888-225-9775 — we carry these knives daily and can narrow it down based on your hand size, carry preference, and budget.

CPM MagnaCut vs. comparable blade steels

SteelToughnessEdge RetentionCorrosion ResistanceSharpenability
CPM MagnaCut ★ExceptionalHighExcellentModerate
CPM-S35VNHighModerateHighEasy
CPM-S30VMod–HighModerateHighModerate
M390ModerateHighHighDifficult
20CVModerateHighHighDifficult
154CMMod–HighModerateAbove avgVery easy
VG-10ModerateModerateHighEasy
Why CPM MagnaCut leads on toughness despite high hardnessMost high-hardness stainless steels sacrifice toughness for edge retention. CPM MagnaCut is the exception: by eliminating chromium carbides and using smaller niobium and vanadium carbides, the steel maintains an intact, tough matrix even at 64 HRC — where M390 or 20CV would become noticeably brittle.
Benchmade, Spyderco & Zero ToleranceThe largest authorized CPM MagnaCut catalog in Louisiana — folders, flippers, and fixed blades from the top three production brands.
Authorized Dealer — Full Warranty CoverageBenchmade LifeSharp: free lifetime sharpening and mechanical repair. Spyderco and ZT manufacturer warranties included on every knife.
Steel Expertise On CallNot sure which CPM MagnaCut model fits your carry? Call 888-225-9775 — we carry these knives daily and know the differences.
Same or Next Business Day ShippingShips from Columbia, Louisiana. Order by 2 PM CT and your CPM MagnaCut knife is on its way today.