M390 steel has earned its reputation recently as the go-to material for premium everyday carry knives, thanks to its practical balance of edge retention, corrosion resistance, and wear resistance. If you want real EDC benefits, look no further than the proven lab data and hands-on user reports that set M390 apart.
What Makes M390 Steel Different
M390 steel comes from Böhler-Edelstahl in Austria, where it is produced by powder metallurgy rather than conventional steelmaking. This process creates a martensitic chromium steel with a chemical composition that reads like a recipe for extreme performance: 1.9% carbon, 20% chromium, 4% vanadium, 1% molybdenum, 0.6% tungsten, 0.7% silicon, and 0.3% manganese. These elements don’t randomly float around in the steel matrix. They form specific carbide structures that determine how the steel performs.
The powder metallurgy process allows these elements to distribute evenly throughout the steel, resulting in approximately 22% total carbide volume, according to metallographic analysis by Knife Steel Nerds. About 18% of this consists of chromium carbides, while 2.5% forms vanadium carbides. This carbide content places M390 in the same category as steels like Maxamet, S90V, and 15V when measured by carbide volume. Most knife manufacturers heat treat M390 to 61-63 HRC, though Böhler’s specifications indicate the steel can reach 59-66 HRC depending on the heat-treatment protocol.
Edge Retention Performance
CATRA testing provides standardized measurements of how long a blade stays sharp when cutting abrasive material. Böhler-Uddeholm’s own CATRA study showed that M390 cut 959mm of cardstock, compared to 547mm for 154CM steel. Production knives show more variation in real-world testing. Knife Steel Nerds reported that Spyderco’s M390 knives tested at 785mm in CATRA trials, while other production M390 knives ranged from 600mm to 750mm depending on heat treatment and blade geometry.
In daily life, those numbers mean fewer sharpenings and more dependable cutting. Everyday carriers report M390 handling months of tough cardboard, rope, and food prep with almost no sharpening needed. Forum users regularly carry M390 blades for a year, through work, travel, and even ocean swims, without worrying about edge loss. One EDC user mentioned stropping only a handful of times after months of outdoor use. Compared to S30V, M390 lets you trust your blade to outlast the job, wherever you carry it.
Toughness Limitations
High carbide content comes with trade-offs. M390’s toughness measures around 5 foot-pounds at 61 HRC in Charpy impact testing, according to data compiled by Knife Steel Nerds. Earlier testing indicated values of 8-9 foot-pounds, but proper heat-treatment protocols showed that these initial measurements were overly optimistic. The steel’s 22% carbide volume creates stress-concentration points that make it prone to chipping under impact or lateral stress.
This doesn’t mean M390 blades break easily during normal use. The limitations of toughness become apparent when users apply excessive force, use the knife for prying, or cut at extremely low angles. Forum discussions consistently mention that M390 performs poorly when used outside its intended purpose. Users who stick to cutting tasks rarely report problems, while those who use their knives as pry bars or impact tools often experience edge chipping.
Corrosion Resistance Data
The 20% chromium content in M390 provides excellent rust resistance. Testing by Knife Steel Nerds using a 1% saltwater spray every eight hours showed that M390 outperformed S30V, S35VN, S90V, and SG2. The steel forms a passive chromium oxide layer on its surface that protects against corrosion in humid environments. M390 didn’t quite match the corrosion resistance of S110V or LC200N, but it exceeded S45VN in testing.
Real users confirm these laboratory results. Multiple forum posts describe M390 knives surviving ocean exposure, frequent food preparation, and constant pocket carry without developing rust or stains. The combination of chromium with molybdenum and tungsten creates what Knife Steel Nerds describes as “very good corrosion resistance” through high chromium in solution. This makes M390 particularly suited for everyday carry, where knives encounter moisture, sweat, and various corrosive substances.
Sharpening Requirements
Getting M390 back to peak sharpness requires specific equipment and technique. Standard whetstones and basic sharpeners struggle with M390’s wear-resistant carbides. Diamond stones or CBN (cubic boron nitride) sharpeners work best, according to experienced sharpeners on knife forums. The chromium carbides in M390 are softer than the vanadium carbides, making them easier to abrade than the carbides in steels like S90V or S110V.
Sharpening experts recommend using diamond or ceramic media specifically designed for high-carbide steels. One forum member noted that M390’s chromium carbides are softer than those in common aluminum oxide sharpening belts, making the steel somewhat easier to sharpen than other super steels. Still, users switching from softer steels like 8Cr13MoV or VG-10 will notice M390 takes longer to sharpen and wears sharpening equipment faster. The time investment pays off through extended periods between sharpening sessions.
Manufacturing and Cost Factors
Powder metallurgy production makes M390 expensive from the start. The steel costs more per kilogram than conventionally produced steels, and its wear resistance creates additional manufacturing challenges. Knife makers report that M390 wears out sanding belts faster and requires more time for grinding and finishing operations. These factors contribute to higher retail prices for M390 knives.
The manufacturing difficulty extends beyond initial production. Custom knife makers charge premium rates for working with M390 because modifications take longer and require more tooling. Production knife companies invest in specialized equipment and processes to work with M390 efficiently, but these costs still affect final pricing. Consumers pay for both the material cost and the additional labor required to transform M390 into finished knives.
Practical Considerations for Users
If you want a knife that keeps cutting, resists rust, and thrives with minimal maintenance, M390 is built for you. Office workers, warehouse pros, and outdoor enthusiasts who use knives for daily cuts, not prying, depend on M390’s edge. Count on it for cardboard, rope, food, plastics, and tough packaging with less downtime for sharpening.
You should also know your needs. If you use your knife for prying or need to resharpen often for the ritual, M390 isn’t ideal. Construction users and regular sharpeners might prefer a tougher, more easily maintained steel. For most EDC users, though, the sharpening challenge is rare and more than offset by lasting performance between sharpenings.
Performance Comparisons
Laboratory testing and user reports consistently place M390 among the top performers for edge retention in stainless steels. The 959mm CATRA result surpasses most commonly available knife steels. Only a handful of steels, such as S90V, S110V, and Maxamet, show better edge retention in standardized testing. M390’s corrosion resistance exceeds that of popular EDC steels like S30V and S35VN while maintaining a competitive edge retention.
The toughness comparison tells a different story. M390’s 5 foot-pounds at 61 HRC falls below steels designed for hard use. CPM-3V, for example, achieves toughness values several times higher than M390. Even within the stainless category, steels like S35VN and 14C28N provide better toughness at the expense of edge retention. These comparisons help users understand that M390 optimizes for specific properties rather than trying to excel at everything.
Our Use of M390 Steel
We use M390 steel in products such as the Micro Shrike, designed in collaboration with Jared Price. This knife features a 2.6-inch M390 blade and an open length of 6.6 inches. The Micro Shrike brings together M390’s edge retention with features like a ball-bearing pivot system and your choice of titanium or micarta scales. Our description of the blade geometry highlights a sharp tip and ample belly, making it suitable for cutting tasks at home, in the office, or at a campsite.
The Micro Shrike shows how M390 fits our approach to everyday carry. The steel’s edge retention provides consistent cutting performance over extended use. Corrosion resistance allows for worry-free daily carry in various environments. The 2.6-inch blade length is legal in most jurisdictions and provides sufficient cutting edge for utility tasks.
Making the Decision
M390 delivers real-world advantages for everyday carriers: industry-leading edge retention, excellent corrosion resistance, and dependable performance from reputable makers. Be ready for less sharpening and more cutting. That said, you should know the trade-offs. A tougher steel may suit you if you pry, and sharpening M390 requires the right equipment. Ultimately, the higher price buys you EDC confidence that few other steels can match.
Your cutting tasks, maintenance preferences, and budget determine if M390 makes sense for your needs. Users who cut frequently but sharpen rarely will maximize M390’s value proposition. Those who need a knife for varied tasks, including some light prying or impact work, might find better options in tougher steels. Understanding these trade-offs based on actual testing data and user experiences, rather than marketing claims, leads to informed purchasing decisions that match steel properties to intended use.