Steel matchup
CPM 20CV and Elmax, compared on the five things that decide a blade: toughness, edge retention, corrosion, heat treat and how each one grinds.
A top-tier powder-metallurgy stainless steel, chemically near-identical to M390, prized for exceptional edge retention and excellent corrosion resistance in premium EDC and outdoor knives.
A premium powder-metallurgy stainless steel from Bohler-Uddeholm, balancing strong edge retention with excellent corrosion resistance and easier sharpening than most steels in its performance class.
Dimension by dimension
Each steel's own note, its score out of five, and what separates the two in that one column. The higher score in a row is marked in purple.
| Dimension | CPM 20CV | Elmax | What separates them |
|---|---|---|---|
| Toughness | The tradeoff for its extreme wear resistance: hardened to 60+ Rc with a heavy carbide load, it is more prone to micro-chipping than tougher steels like CPM 3V or CruWear. | Fine, round carbides from the powder-metallurgy process give it good toughness for a high-carbide steel, with minimal risk of edge chipping when hardened correctly. | Elmax is clearly tougher. Its fine, round powder-metallurgy carbides give it real resilience against chipping, while CPM 20CV's heavier carbide load at typical working hardness makes it more prone to micro-chipping at the edge. |
| Edge retention | Exceptional wear resistance from a very heavy chromium and vanadium carbide load, among the best edge retention available in a knife steel. | Strong wear resistance from a heavy vanadium and chromium carbide load, holding an edge well in everyday-carry and outdoor use. | CPM 20CV holds a modest edge here thanks to its higher carbide volume, though the practical difference in sharpening interval is smaller than the toughness gap running the other way. |
| Corrosion resistance | 20% chromium gives it excellent, top-tier stainless performance, a strong choice for wet, humid, or marine environments. | 18% chromium puts it among the best corrosion resistance of any premium knife steel, a strong choice for marine or wet environments. | Essentially tied. Both use roughly 18-20% chromium and are considered top-tier for stainless corrosion resistance. |
| Heat treat | A validated recipe from independent toughness testing: austenitize at 2140 F, plate quench, apply a cryogenic treatment, then temper at 365 F. Most knifemakers target the 60-62 Rc range. Because this steel demands precise, high-temperature equipment and a controlled quench, it is best suited to makers with a programmable oven or a professional heat-treating service. | Austenitize at 1975-2050 F (1080-1120 C). Air or plate quench, then apply a cryogenic treatment (liquid nitrogen or dry ice) before tempering to reduce retained austenite and boost hardness. Double temper at 350-400 F for 2 hours per cycle. Maximum working hardness is around 62 Rc, though most production knives run 60-61 Rc. | CPM 20CV demands a notably higher, more precise austenitizing temperature (around 2140 F) that benefits from professional-grade equipment. Elmax is also a demanding steel to heat treat well, but is generally considered somewhat more forgiving than CPM 20CV. |
| Grinding | Demanding to grind and sharpen; typically requires diamond or CBN abrasives to sharpen efficiently once fully hardened, more challenging than most other steels in this database. | One of the easier premium powder-metallurgy steels to sharpen for its performance level, though still slower to grind than basic stainless steels. | Elmax is easier to grind and, notably, easier to sharpen than CPM 20CV, which is one of the more demanding steels in this database to bring back to a clean edge. |
Best use
CPM 20CV
Choose CPM 20CV when maximum edge retention is the single top priority and you have access to precise heat treating and diamond or CBN sharpening equipment.
Open the CPM 20CV referenceElmax
Choose Elmax for a more forgiving, well-rounded premium stainless steel that is meaningfully tougher and easier to maintain day to day.
Open the Elmax reference
The long answer
CPM 20CV and Elmax are both loaded with chromium and vanadium for outstanding wear resistance and corrosion resistance, and both are frequently cross-shopped by anyone looking at premium production knives from European and American makers alike. The real gap between them shows up in toughness and how demanding each one is to sharpen.
Keep comparing
Keep reading
CPM 20CV sits alongside CPM S30V and CPM M4 among the more demanding steels in this database to grind and sharpen. The same heavy chromium-vanadium…
Elmax sits in the moderately demanding middle tier of powder-metallurgy stainless steels, tougher and easier to work than harder-edged steels like CPM…
Every knife steel is iron plus a specific recipe of other elements, and each of those elements pulls the steel’s behavior in a particular direction…
Same bench
Whichever steel wins, the grind is only as flat as the platen behind it. I machine the parts, hand-assemble, track and test Torus grinders in Sterling, Illinois.
Current dual-axis platform with a fiber-laser-cut 6061 chassis and single-knob tracking.
Current dual-axis platform with a steel chassis, more mass and less vibration.
Prior-design aluminum chassis, 90-degree tilt and 1.5-inch tooling arms.
One-man shop
Tell me what the blade is for and how you heat treat, and I will tell you which of these I would put on the bench — including when the answer is neither.
