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CPM MagnaCut is the first powder-metallurgy stainless tool steel that nails the knife “holy trinity”—high wear resistance, high toughness, and real-world stainlessness—at 60-64 HRC.
Think pocket-knife edges that stay razor-sharp, camp blades that shrug off batoning, and gyutos that laugh at sushi-bar humidity. MagnaCut pulls this off by eliminating chromium carbides—the gritty Achilles heel of traditional stainless steels—and replacing them with tiny vanadium-niobium carbides inside a uniform PM matrix.
Why you should care: Forget the old triangle where you must pick two of edge life, toughness or corrosion resistance. MagnaCut lets you tick all three boxes and still sharpen without throwing sparks halfway across the workshop.
Metallurgist Dr. Larrin Thomas partnered with Crucible Industries to design MagnaCut, purpose-built for knives rather than repurposed from an industrial die steel.
Traditional ingot steels cool slowly; elements segregate, and chromium grabs carbon to form 5-10 µm carbides—great for wear, awful for toughness and corrosion. PM freezes the alloy so quickly that carbon pairs with vanadium/niobium first, leaving chromium dissolved in the matrix to fight rust. The result is an 8 % volume of fine MC carbides (VC + NbC) evenly sprinkled like pepper, not rock salt boulders.
1.15 %C, 10.7 %Cr, 4 %V, 2 %Nb, 2 %Mo, 0.20 %N—the deliberate mix that lets MagnaCut dodge chromium-carbide formation.
| Element | Job Description |
|---|---|
| C 1.15 | Creates martensite; feeds carbides for edge life |
| Cr 10.7 | Forms stainless film; solid-solution strength |
| V 4.0 / Nb 2.0 | Builds ultra-hard MC carbides (VC/NbC) for wear and grain refinement |
| Mo 2.0 | Secondary hardening, hot-strength, temper resistance |
| N 0.20 | Stabilises austenite; boosts hardness & pitting resistance |
Why the chromium is “low”: At ~11 %, Cr supplies rust protection but not enough carbon to spawn large Cr23C6 carbides. Vanadium & niobium hog the carbon instead, sidestepping the brittleness tax.
MagnaCut posts ~135 % CATRA vs 440C, ~38 ft-lbs Charpy at 62.5 HRC, and salt-spray scores that nip at LC200N’s heels.
Call-out Box – Knife-Steel 101
HRC (Rockwell Hardness): Measures how hard the martensite matrix is; higher means better edge holding but more risk of brittleness.
Carbides: Microscopic hard particles (VC, NbC) that slow abrasive wear.
PM (Powder Metallurgy): Atomises molten steel into powder and HIPs it—locking carbides tiny and evenly spaced.
Austenitise 2050 °F / 1120 °C, plate-quench, cryo, double temper 350 °F for an easy 61–63 HRC.
| Step | Preferred Range | Rationale |
|---|---|---|
| Forge (if at all) | 2100 °F → stop @ 1750 °F | Hotter risks grain growth; most makers stock-remove. |
| Austenitise | 1950–2200 °F (2050 sweet spot) | Higher temp = higher HRC, lower temp = max toughness. |
| Quench | Plate or 2-bar N₂ to < 125 °F | Fast enough to bypass pearlite nose. |
| Cryo | Dry ice or liquid N₂ immediately | Drops retained austenite from ~8 % → 2 %; +1 HRC. |
| Temper | Two cycles @ 300–450 °F (350 ideal) | 2 h each; stay < 750 °F or corrosion resistance dives. |
Shop notes: MagnaCut grinds easier than 20CV; SG alumina or CBN wheels shine. For sharpening, coarse diamond < 400 grit resets an apex fast, while 1 µm CBN strops bring mirror polish in under 60 s.
If your blade touches salt, bone, or frozen wood, MagnaCut is the closest thing to cheat-code steel.
Sweat, fruit acids and the odd cardboard binge—MagnaCut shrugs them off at 0.010-in edges. Benchmade’s 940-2 MagnaCut runs 61 HRC and real-world users report one-month pocket carry with zero rust bloom.
Charpy toughness plus stainless behaviour means you can baton wet birch and carve tinder without babying the edge. Many bush-craft makers keep it at 60 HRC for fixed blades 5–9 in long—essentially “stainless 3V.”
Fine grain supports 10 dps edges; sushi chefs love the water-beading finish. Unlike high-carbide steels, MagnaCut takes a near-hazy kasumi without scratching stones.
MagnaCut seldom tops every chart, but no rival matches its triple-threat balance.
| Property | MagnaCut | M390/20CV | S45VN | CPM 4V | Cru-Wear | S90V |
|---|---|---|---|---|---|---|
| Toughness | ★★★★☆ | ★★☆☆☆ | ★★☆☆☆ | ★★★★☆ | ★★★★☆ | ★☆☆☆☆ |
| Edge Life | ★★★★☆ | ★★★★★ | ★★★★☆ | ★★★★☆ | ★★★★☆ | ★★★★★★ |
| Corrosion | ★★★★☆ | ★★★★☆ | ★★★☆☆ | ★★☆☆☆ | ★★☆☆☆ | ★★☆☆☆ |
| Sharpening Ease | ★★★★☆ | ★★☆☆☆ | ★★★★☆ | ★★★☆☆ | ★★★☆☆ | ★☆☆☆☆ |
Key Takeaways
Video Credit: Knife Steel Nerds
From $150 production folders to boutique custom knives, MagnaCut shows up everywhere.
| Brand / Model | Blade L (in) | Typical HRC | Notable Feature |
|---|---|---|---|
| Spyderco Para 3 Salt | 3.0 | 62–63 | LC200N liners + MagnaCut blade; fully marine-proof |
| Benchmade 940-2 MagnaCut | 3.4 | 61–62 | Green-anodised classic gets a stainless-tool-steel heart |
| Demko AD20.5 | 3.2 | 62 | Shark-Lock meets all-weather steel |
| Hogue Deka v2 | 3.25 | 62 | 2.4 oz ultralight with ABLE-Lock |
| White River FC7 | 7.0 | 61 | Firecraft survival knife—ferro-rod notch, no chipping |
| Bark River Bravo-1 MagnaCut | 5.8 | 60 | Convex bush-craft classic now rust-proof |
| Terzuola ATCF Custom | 3.6 | 64 | 0.012-in edge, carbon-fiber scales |
| Kershaw Livewire OTF | 3.3 | 61 | First mass-market OTF in MagnaCut under $300 |
| Question | One-Sentence Answer |
|---|---|
| Is MagnaCut truly stainless? | Yes—its pitting resistance eclipses S35VN and shadows LC200N in real EDC. |
| What hardness should I ask my maker for? | 62 HRC is the sweet spot; 64 HRC for slicers, 60 HRC for choppers. |
| Does it sharpen like S30V? | Slightly faster—lower carbide volume and finer particles. |
| Can MagnaCut rust? | Only with prolonged neglect; rinse salt water and you’re golden. |
| Is it overkill for a kitchen petty? | Not if you want laser-thin, stain-proof edges that hold 10° inclusive. |
MagnaCut isn’t marketing fluff; it’s metallurgy with intent. In the knife-steel arms race, it’s the rare alloy that lets you have your cake and baton it too. Whether you’re a chef chasing stone-polished gyutos, a hunter sick of edge chips, or a maker tired of choosing between rust spots and snapped tips, MagnaCut earns its spot in your lineup—and likely keeps it for the rest of the decade.
In January 2025 Crucible Industries, the sole U.S. producer of CPM-series steels, filed for Chapter 11 and signaled a full plant shutdown by March. Dr. Larrin Thomas broke the story on KnifeSteelNerds, outlining possible outcomes for MagnaCut: licensing the alloy to another powder-metal mill (Niagara Specialty Metals has been floated) or temporary outsourcing to Erasteel’s French facility. Either path would keep the chemistry identical; only lead-times and pricing might wobble during the transition. Knife Steel Nerds
Reddit’s r/knives community quickly dissected the news, noting that most CPM recipes (except patent-protected 15V/20V) are already on the auction block and should be picked up by new owners. The consensus: expect a few months of scarce bar stock, but MagnaCut isn’t disappearing—just changing foundries. Reddit
Bottom line for buyers and makers: if you’re eyeing a MagnaCut blade, grab it sooner rather than later; prices may spike until the new producer spins up. For knife makers, lock in bar orders or be ready to slot in alternate stainless like M390 for interim runs. I’ll update this guide when firm production timelines surface.
Author: Aleks Nemtcev | Knifemaker with 10+ Years of Experience | Connect with me on LinkedIn |
References:
CPM MagnaCut Datasheet: download .pdf
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