M390 vs S90V vs Elmax vs CPM-20CV: The Ultimate Premium EDC Knife Steel Comparison 2026

## Introduction If you already know that 14C28N and Nitro-V are solid budget performers, you're ready for the big leagues. Premium powder metallurgy steels like **M390**, **S90V**, **Elmax**, and **CPM-20CV** occupy the top tier of EDC knife blade materials — offering extreme edge retention, exceptional corrosion resistance, and the ability to take a very fine edge. But with prices ranging from $120 to over $400, choosing between them requires understanding real-world trade-offs, not just spec sheet numbers. This comparison breaks down how M390, S90V, Elmax, and CPM-20CV perform across the metrics that matter: edge retention, toughness, corrosion resistance, sharpenability, and value. We'll ground every claim in production knives you can actually buy from Kizer, WE Knife, and ArtisanCutlery. For a budget-oriented companion piece, see our [budget steel comparison guide](/posts/14c28n-vs-ar-rpm9-vs-nitro-v-vs-s35vn-edc-knife-steels-compared-2026) covering the sub-$60 tier. ## What Makes These Steels Premium? All four steels are **powder metallurgy (PM)** products. Unlike conventional ingot steels, PM manufacturing atomizes molten steel into fine powder, then sinters it under heat and pressure. The result is a much finer and more uniform carbide structure — which translates directly into better edge retention and toughness at high hardness. | Property | M390 (Böhler) | CPM-20CV (Crucible) | S90V (Crucible) | Elmax (Uddeholm) | |----------|--------------|-------------------|-----------------|-------------------| | **Edge Retention** | ⭐⭐⭐⭐⭐ | ⭐⭐⭐⭐⭐ | ⭐⭐⭐⭐⭐ | ⭐⭐⭐⭐ | | **Corrosion Resistance** | ⭐⭐⭐⭐⭐ | ⭐⭐⭐⭐⭐ | ⭐⭐⭐⭐ | ⭐⭐⭐⭐ | | **Toughness** | ⭐⭐⭐ | ⭐⭐⭐ | ⭐⭐ | ⭐⭐⭐⭐ | | **Sharpenability** | ⭐⭐ | ⭐⭐ | ⭐⭐ | ⭐⭐⭐ | > Data reference: Steel compositions and properties are sourced from Knife Steel Nerds, powder metallurgy processing overview on Wikipedia, and manufacturer data sheets. ## M390 — The All-Rounder Gold Standard Böhler M390 is arguably the most famous premium EDC steel. Its composition of approximately 20% chromium, 4% vanadium, and 1.9% molybdenum gives it an extraordinary balance of edge retention and stainlessness. **Why choose M390:** - Exceptional edge retention — outlasts S35VN by 2-3x in CATRA testing - Near-perfect corrosion resistance — essentially stainless in all but extreme saltwater - Takes a very fine, aggressive edge **The trade-off:** M390 is notoriously difficult to sharpen. Diamond abrasives are practically required, and reprofiling can be time-consuming. **Representative knives:** - The **Kizer Drop Bear Zero M390** ($199.95) pairs M390 with Kizer's Button Liner Lock in a titanium/DLC build on [its product page](/products/drop-bear%C2%AE-zero-|-kizer-button-liner-lock%E2%84%A2-+-titanium-damascus-|-m390-+-polished-dlc-ultra-+-hollow-grind-|-dlc-titanium-|-kizerb%E2%84%A2-3619bda6-7121). - The **WE Knife Fluxor M390** ($343) is a titanium-handled flipper with nested liner lock — [see it here](/products/weknife-fluxor-we23071-1-m390-nested-liner-lock). - The **ArtisanCutlery Tomahawk M390** ($224.99) offers M390 in a titanium handle package — [product details](/products/artisan-cutlery-tomahawk-atz-1815g-m390-blade-titanium-handle-folding-knives). ## CPM-20CV — M390's American Cousin CPM-20CV is Crucible Industries' version of M390. The compositions are nearly identical (both hover around 20% Cr, 4% V, 1% Mo), and in blind testing most users cannot tell them apart. **Why choose 20CV:** - Identical performance to M390 at potentially lower cost - Excellent for users who prioritize maximum edge holding over ease of sharpening - American-made alternative **Where to find it:** The **Kizer Drop Bear Clutch Lock 20CV Fatcarbon** ($198) is an excellent entry point — [product page](/products/drop-bear%C2%AE-|-kizer-clutch-lock-|-20cv-|-fatcarbon-|-kizerb-3619a1). ## CPM-S90V — Maximum Abrasion Resistance S90V takes edge retention to another level by packing approximately **9% vanadium** into the alloy — more than double the vanadium content of M390/20CV. **Why choose S90V:** - The highest edge retention of any mainstream stainless steel - Outlasts M390 by roughly 20-30% in abrasive cutting tests - Excellent corrosion resistance (though slightly less than M390) **The trade-off:** S90V is even more challenging to sharpen than M390. Its toughness is also the lowest of this group. **Representative knives:** - The **ArtisanCutlery Fragarach S90V** ($199.99) combines a titanium handle with S90V — [see it here](/products/artisan-cutlery-fragarach-atz-1879g-s90v-blade-titanium-handle-folding-knives-2109). - The **ArtisanCutlery Wizard S90V Copper** ($139.99) offers S90V with a copper handle — [product page](/products/artisancutlery-wizard-atz-1870g-s90v-steel-blade-copper-handle-folding-knives-4585). ## Elmax — The Tough Performer Uddeholm Elmax prioritizes **toughness** over raw edge retention. With its fine and evenly distributed carbide structure, it offers superior impact resistance. **Why choose Elmax:** - Best toughness of any premium PM stainless steel - Still offers very good edge retention (close to S35VN) - Easier to sharpen than M390 or S90V - Good corrosion resistance **Representative knives:** - The **Kizer Drop Bear Zero Elmax** ($189.95) pairs Elmax with crystallized titanium — [product page](/products/drop-bear%C2%AE-zero-|-kizer-button-liner-lock%E2%84%A2-|-elmax-+-hand-brushed-+-hollow-grind-|-crystallized-titanium-|-kizerb%E2%84%A2-3619bda5-4215). - The **Kizer Drop Bear Clutch Lock Elmax Fatcarbon** ($219) gives you Elmax in a crossbar-style lock platform. ## Head-to-Head Comparison ### Edge Retention **S90V > M390 ≈ 20CV > Elmax** In standardized CATRA tests, S90V outperforms M390 by about 25% in edge retention. M390 and 20CV are essentially tied. Elmax trails by roughly 30%, but still outperforms S35VN by a comfortable margin. ### Toughness **Elmax > M390 ≈ 20CV > S90V** Elmax is in a different league for toughness. S90V demands respect — run a slightly more obtuse edge angle (17-20°) to compensate. ### Corrosion Resistance **M390 ≈ 20CV > S90V > Elmax** M390 and 20CV are effectively stainless in any EDC context. S90V is close behind. Elmax can develop surface stains if neglected in very humid environments. ### Sharpenability **Elmax > M390 ≈ 20CV > S90V** Elmax responds reasonably well to conventional alumina stones. M390 and 20CV need diamond or CBN. S90V demands diamond abrasives and patience. ## Which Should You Buy? **Choose M390 or 20CV** if you want the best all-around premium steel — excellent edge retention, total stainlessness, and a proven track record. **Choose S90V** if edge retention is your absolute priority and you're willing to invest in diamond sharpening equipment. **Choose Elmax** if you want premium corrosion resistance with better toughness and easier sharpening. It's the most forgiving premium steel for daily carry. For the full Kizer lineup, check our [Kizer knife buying guide](/posts/kizer-knives-guide-2026-budget-to-premium). For WE Knife's premium offerings, see our [best WE Knife titanium folders guide](/posts/best-we-knife-titanium-folders-2026). ## Conclusion There's no wrong answer among these four steels — they all outperform budget options by a wide margin. Your choice comes down to your priorities: maximum edge holding (S90V), best all-round balance (M390/20CV), or superior toughness with easier maintenance (Elmax). For those on a tighter budget wondering if the upgrade is worth it, our [EDC knife sweet spot guide](/posts/edc-knife-sweet-spot-70-to-100-dollars-kizer-civivi-vosteed-cjrb-2026) covers the $70-100 range where premium-adjacent steels like S35VN offer much of the performance at half the price.