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N690 is a cobalt-alloyed stainless knife steel made by Böhler. It offers a useful balance of corrosion resistance, wear resistance, and manageable sharpening for everyday carry, hunting, and general outdoor cutting. Often labeled N690Co, it is a conventional steel rather than a powder metallurgy grade. A well-made N690 knife can be a practical choice, but its heat treatment and edge geometry matter as much as the name on the blade.
N690 is a high-carbon martensitic stainless steel containing chromium, molybdenum, cobalt, and a small vanadium addition. Böhler identifies it as 1.4528 / X105CrCoMo18-2. It is used in production blades and custom knives, as well as industrial cutting applications.
The alloy’s value comes from the combination of a hardenable matrix, wear-resistant carbides, and corrosion resistance. It should not be judged by its chromium percentage alone: heat treatment determines how much alloy remains in solution and how the finished blade behaves.
Böhler produces the grade. Knife companies and independent knifemakers then choose the blade design, heat treatment, grind, and finish. Those decisions explain why two knives made from N690 can feel different in use. A maker’s name on a finished knife is separate from the steel producer’s alloy designation.
Molybdenum contributes to corrosion behavior and the carbide system. Cobalt influences the response to heat treatment, while abrasive wear resistance depends on the hardened matrix and its carbides. The complete composition and thermal cycle determine the final balance of properties.
N690 belongs to the conventional, ingot-produced stainless steel family. It is not a CPM or other powder metallurgy steel. Stock is worked into useful shapes and supplied in a condition suitable for further machining and heat treatment.
Electroslag remelting, or ESR, is a separate refining process that can improve steel cleanliness. For a particular N690 blank, confirm the melting route in its material certificate. The name N690Co highlights cobalt content; the documented product variant identifies how the stock was produced.
Hot working converts cast stock into usable bar or strip and changes its internal structure. For a knife maker, stock quality, machining allowances, and the thermal cycle are the practical points to control.
Where specified, ESR can reduce certain nonmetallic inclusions, benefiting consistency and polishability. Finished-blade performance also depends on heat treatment, carbide structure, and the amount of support behind the cutting edge.
N690 offers good stainless performance and useful wear resistance for ordinary knife work. Its toughness is a compromise: it is not the first choice when maximum resistance to impact or lateral loading takes priority over wear resistance. Edge retention also includes resistance to rolling and chipping, not just resistance to abrasion.
Finished N690 knives commonly fall around 58–61 HRC, depending on the manufacturer and intended use. A lower value does not automatically mean poor heat treatment, and a higher value does not establish a better knife. Compare hardness alongside blade thickness, the thickness behind the edge, and the cutting task.
N690 resists ordinary moisture well with reasonable care, but it can stain or pit in saltwater, sweat, and damp storage. Total chromium content is not the same as chromium dissolved in the hardened matrix. Surface finish and heat treatment also affect corrosion, so a universal ranking based only on composition is unreliable.
For frequent marine use, consider a knife specifically designed and documented for that environment. A stainless label does not remove the need to rinse away salt and dry the blade.
The composition below is nominal, by weight, from Böhler’s September 2026 technical datasheet. Physical properties are listed at 68°F (20°C).
The following comparisons describe useful selection differences rather than a universal ranking. A thin, well-sharpened blade can cut more efficiently than a thicker blade in a more wear-resistant steel.
VG-10 and 440C are useful comparison points, but neither is chemically identical to N690. Treat “equivalent” as a broad performance comparison unless a specification explicitly permits substitution. N695 is also a separate grade; a similar name is not proof that a knife uses N690.
N690, VG-10, and 440C can all make capable stainless blades. N690 and VG-10 both contain cobalt, but their chemistry differs. Takefu’s representative VG-10 table lists 1.55% cobalt, close to N690’s 1.5%. Cobalt content alone cannot predict which finished edge will last longer.
For field knives, choose a suitable grind and enough edge support for the work. Do not infer resistance to twisting or impacts from a steel label. Neither N690 nor VG-10 makes a thin knife suitable for prying.
N690 is generally manageable on quality aluminum-oxide or silicon-carbide stones. S30V’s greater vanadium-carbide content can make conventional abrasives less efficient; diamond or CBN is useful for both steels, especially for repairs. The amount of metal removed, stone condition, bevel width, and burr control can outweigh the alloy difference.
In abrasive slicing, N690 generally offers more wear resistance, while 14C28N is attractive for its toughness and ability to support a fine edge. That does not mean an N690 knife will always cut longer. A thinner 14C28N blade may need less force, and an edge that avoids damage may remain useful longer in demanding work.
Alleima specifically emphasizes edge sharpness, edge stability, and corrosion resistance for 14C28N, listing applications that include fishing knives and kitchen knives. Compare actual hardness and geometry rather than assuming either alloy wins every task. Our 14C28N steel guide covers that alternative in more detail.
A 2022 study by Dong Wu, Qinyi Zhang, and Wei Liu compared 154CM, 440C, and N690 blades under a shared heat-treatment and cutting-test protocol. The specimens were approximately 57 HRC; 154CM achieved about 25% more total card cutting than the other two. This was a result for those specimens, not a guarantee for every commercial knife.
Standardized testing separates initial sharpness from retained cutting ability. CATRA describes blade testing to EN ISO 8442-5, which provides a framework for evaluating cutting performance under controlled conditions. Compare test figures only when hardness, geometry, sharpening, and the test method are known.
N690 appears in European folders, hunting knives, and outdoor fixed blades. Extrema Ratio and FOX are documented users. Check the exact model and production version, because manufacturers can offer different steels under related names.
It provides an established stainless option with useful wear resistance, good polishability, and a familiar manufacturing route. Those are practical reasons to use it in production.
Böhler lists industrial cutting instruments and food-processing components among its applications. These uses call for a combination of wear resistance, corrosion resistance, and a finish suited to the working environment.
Böhler’s datasheet specifies austenitizing at 1,886–1,976°F (1,030–1,080°C), with a 15–30 minute hold after complete heating, followed by rapid quenching to approximately 86°F (30°C) and immediate tempering. These are manufacturer guidelines, not a complete recipe for every blade thickness, furnace, and quench system.
The current sheet gives a tempering range of 212–392°F (100–200°C) and a minimum hold of two hours. Its hardness-chart example uses two two-hour tempers after hardening at 1,886°F (1,030°C), on a 0.79-inch (20 mm) square specimen, and reports hardness up to 59–61 HRC. Keep those example conditions separate from a validated knife-specific process.
Subzero treatment can change retained austenite and hardness, but the current N690 sheet does not provide a universal cryogenic cycle. Have the heat treater establish the complete sequence and verify the result.
The appropriate quench depends on section size, equipment, and the validated process. The current sheet calls for rapid quenching without prescribing one universal plate setup, oil speed, or cooling time for every knife. Use the stock-specific instructions and a heat treater experienced with this grade. An improvised water quench carries an avoidable cracking risk.
Control the austenitizing temperature and hold time, and use suitable atmosphere or foil protection against oxidation and decarburization. Surface protection does not itself prevent grain growth. Furnace calibration, adequate quenching, and hardness checks are part of process control; color alone is not a reliable guide for hardening this alloy.
Start with an abrasive coarse enough to remove the damage or establish the bevel. For routine sharpening, a medium stone followed by careful deburring is usually more useful than a long polishing progression. Diamond and CBN are convenient, but N690 does not require them for every touch-up.
A roughly 1,000–3,000-grit finish is a practical starting point for general slicing, with the caveat that grit systems differ. A coarser edge may retain more bite in rope or packaging; a finer finish can improve some push cuts. Choose the finish for the material being cut.
About 17–20 degrees per side is a reasonable starting range for many general-purpose knives, not a Böhler specification or a limit for all N690 blades. This means a 34–40-degree included angle. Keep the maker’s angle initially if the edge already performs well.
If the edge chips or rolls, increase support with a slightly more obtuse bevel or microbevel. A microbevel supports the apex by increasing its local edge angle. Use light finishing pressure and remove the burr rather than polishing a weakened wire edge.
Light stropping can remove residual burr material and provide fine abrasion. It cannot repair chips or restore missing steel. Excess pressure on a soft strop can round the apex, so stop when it no longer improves the cut and return to a stone when needed.
Diagnose the edge before changing the sharpening method. Abrasive wear, a rolled apex, chips, and a remaining burr are different problems. Rust spots are a surface-care issue rather than evidence that the blade is not stainless.
Chipping can result from an edge that is too thin for the task, impacts against hard material, lateral force, or problems with heat treatment or grinding. Match edge support and hardness to the cutting task.
Sharpen past the damaged area, add a small microbevel if appropriate, and avoid twisting the blade in a cut. Repeated damage during ordinary use warrants discussion with the maker. A user should not attempt to correct suspected heat-treatment problems by reheating a finished knife.
Brown or orange spots on N690 may be corrosion rather than a stable protective patina. Wash and dry the blade first. If necessary, use a mild polish compatible with its finish, testing an inconspicuous area. Abrasive pastes can change a satin or mirror finish, and deep pitting cannot be wiped away.
Choose N690 when the knife’s design, fit, and heat treatment suit your work and you want a stainless blade with manageable maintenance. EDC, hunting, food preparation, and ordinary outdoor cutting are reasonable uses. For heavy impacts, very thin edges, or prolonged saltwater exposure, compare steels and designs chosen specifically for those demands.
Among higher-performance CPM steels, MagnaCut illustrates a different balance of properties. A premium alloy can be useful, but it does not compensate for poor geometry or an uncomfortable handle.
S35VN is a powder metallurgy stainless steel with vanadium and niobium additions. It is worth considering when abrasive edge wear is a frequent problem and you are comfortable using suitable abrasives. Compare hardness, geometry, and credible testing of the actual designs to judge whether the extra wear resistance is useful for your work.
14C28N can be the better fit when toughness, a fine cutting edge, and straightforward sharpening matter more than maximizing abrasive wear resistance. Its lower price category does not make it inferior for every use. Higher hardness can reduce toughness, so the heat treatment should suit the intended edge geometry.
Read next: Knife Steel Chart
For a finished knife, confirm the exact steel, maker, hardness specification, and blade geometry. For raw stock, request the grade and material documentation, dimensions, delivery condition, and whether any remelting process is specified. The steel name alone is not enough to compare offers.
Available dimensions and finishes depend on the documented stock variant. Select thickness for the intended blade, allowing for grinding, scale removal, and straightening where needed. Precision-ground stock can save preparation work, but a guaranteed flatness tolerance must come from the actual specification.
Wash away dirt and food residue, rinse with fresh water after exposure to salt or sweat, and dry the blade, pivot area, and handle joints. Use a thin suitable protective oil when storage conditions warrant it.
Store the knife dry. A damp leather sheath can retain moisture against the blade, so remove the knife for extended storage. Touch up the edge before it becomes badly worn, and use a stone when a rod or strop no longer restores useful cutting.
Mild dish soap and water are sufficient for most cleaning. Food-grade mineral oil is a simple option for blades used around food. Products such as Tuf-Glide or Ballistol should be selected according to their current label and the intended use; do not assume every lubricant is suitable for food contact. Avoid bleach and cleaners incompatible with the handle, coatings, or adhesives.
No. N690 is conventionally produced. ESR, where documented, is a refining process rather than powder metallurgy.
N690Co is a common knife-industry name for N690, emphasizing its cobalt content. It does not identify a separate premium grade or guarantee ESR.
Yes. Böhler lists N690 as approved for food and beverage contact. A suitable grind, heat treatment, and finish can make it useful for food preparation. Wash and dry the knife after use, and avoid cutting bones or frozen food with a thin edge.
It can stain or pit, particularly when salt and moisture remain on the surface. Stainless means corrosion-resistant, not rust-proof.
A uniform satin finish can make everyday wear less conspicuous than a mirror polish. Match the existing scratch direction and abrasive system; there is no single grit that suits every finish.
N690 remains a sensible option when the complete knife suits the task. Its appeal is a practical balance of stainless performance, wear resistance, and sharpening effort. Compare it with powder super-steels through the work you actually do, rather than treating price or alloy content as a quality score.
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