Swedish Knife Steel: From AEB-L to Damasteel
Swedish steel has been traded on its reputation for centuries. Long before powder metallurgy, stainless steel or laboratory-controlled heat treatment, iron from Sweden was valued for its purity and consistency. The tools have changed since then, but the underlying preoccupation has not: control the material closely enough and it will support a better edge.
That tradition now reaches the kitchen through several distinct families of steel. Uddeholm developed AEB-L and 26C3 for razors and scalpels. Sandvik—whose materials business is now Alleima—built an influential family of fine-carbide stainless cutlery steels that includes 12C27, 13C26 and 14C28N. In Söderfors, expertise in powder metallurgy led to RWL34 and eventually Damasteel.
These steels do not perform identically, nor are they produced by the same method. What they share is a Swedish approach to steelmaking that prizes cleanliness, fine structure and predictable performance at a very thin edge.
Lead image courtesy of Damasteel. Photograph by Albin Bogren.
Before knife steel: why Swedish iron mattered
Sweden’s reputation did not begin with modern alloys. Iron from Dannemora and the surrounding Uppland fields contained unusually low levels of elements such as phosphorus and sulphur, impurities that could make iron brittle or inconsistent.
During the seventeenth century, Walloon ironworkers brought specialised refining methods to Sweden. The resulting bar iron—often exported through Öregrund—became highly valued abroad. By the eighteenth century, England was importing substantial quantities for its growing steel industry, and Swedish Walloon iron retained an important position in Sheffield.
“Swedish steel” therefore meant something before anyone could describe a carbide under a microscope. It referred to material that could be trusted because careful ore selection, charcoal smelting and disciplined refining had controlled what was—and just as importantly, what was not—inside it.
Modern steelmaking no longer depends on the special character of one ore body. Electric melting, controlled alloying and advanced refining allow composition to be engineered with far greater precision. But the reputation outlived the geology because the knowledge remained: generations of mills, metallurgists and smiths continuing to solve difficult material problems for customers who noticed the difference.
Three Swedish routes to a fine edge
The Swedish steels used in modern kitchen knives come from more than one mill and more than one manufacturing tradition.
At Uddeholm, the challenge was precision strip for razors and surgical scalpels. At Sandvik, it was the industrial development of clean, fine-carbide stainless steels for blades and other demanding applications. At Söderfors, conventional steelmaking evolved into gas atomisation and powder metallurgy.
Each route arrived at fine edge performance differently.
A razor strip needs to be rolled with remarkable consistency, formed without cracking, hardened efficiently and ground to an acute edge without that edge breaking down. These demands favour controlled chemistry, small carbides and fine grain.
Powder metallurgy addresses a different problem. Highly alloyed steels can form large, unevenly distributed carbides when a conventional ingot cools. Gas atomisation breaks molten steel into tiny droplets that solidify rapidly. The powder is then consolidated under heat and pressure, producing a more even distribution of its alloying elements and carbides.
For a kitchen knife, the intended result is similar: a structure fine and consistent enough to support a thin, stable and highly refined edge.
AEB-L: stainless razor steel with a second life
AEB-L is one of the clearest examples of an industrial steel finding an ideal second purpose.
Uddeholm developed UHB AEB-L as a more corrosion-resistant material for razor blades, with the grade patented in 1928. Razor steel has little room for metallurgical excess. Large carbides can interrupt an extremely fine edge; insufficient toughness can allow it to chip; poor corrosion resistance is hardly desirable in a blade repeatedly exposed to water.
AEB-L solves this with relatively restrained chemistry. Its carbon and chromium are balanced to provide stainless behaviour and useful hardness without producing the abundance of large carbides found in many more heavily alloyed stainless steels.
That makes AEB-L somewhat deceptive. Its composition does not look exotic, but the absence of excess is precisely the point.
In a well-made kitchen knife, AEB-L can offer:
- A very fine and stable edge
- Excellent toughness for a stainless knife steel
- Easy, responsive sharpening
- Good corrosion resistance
- Strong support for thin blade geometry
- Less tendency toward stubborn burrs than many high-alloy stainless steels
AEB-L also demonstrates why the steel name cannot tell the whole story. The alloy creates the potential; heat treatment and geometry determine how much of that potential reaches the cutting board. In the hands of a skilled maker, AEB-L can be ground thin and hardened for serious performance without becoming needlessly difficult to maintain.
It will be an increasingly important part of the Modern Cooking collection. Two forthcoming lines from New Zealand maker Skye Eilers will use AEB-L, bringing a Swedish razor-steel tradition into a distinctly contemporary New Zealand body of work.
The steel may begin in Sweden, but the finished knife belongs equally to the maker who heat-treats, grinds and gives it geometry.
26C3: the carbon side of the razor tradition
Uddeholm’s other important contribution to this story is UHB 26C3, a high-carbon steel developed for razor and scalpel production.
Its nominal composition contains approximately 1.25% carbon, with small additions of manganese, silicon and chromium. It contains no significant molybdenum, vanadium or tungsten. Rather than relying on large quantities of hard alloy carbides, it develops a very fine structure built primarily around iron carbide.
For a kitchen knife, this provides an attractive combination: high attainable hardness, a keen edge and unusually direct sharpening behaviour.
The steel is often called “Spicy White,” a nickname associated with American bladesmith Devin Thomas. The reference is to Japanese white paper steel. Both are clean, simple carbon steels capable of exceptional sharpness, but the small chromium and manganese additions in 26C3 give it somewhat greater hardenability. A maker can quench it in fast oil rather than relying on the more severe water quench traditionally associated with white steel.
On the stones, 26C3 feels immediate. It raises a burr quickly, refines cleanly and readily takes a polished, acute edge. That makes it particularly rewarding for cooks who sharpen their own knives and value the connection between steel, stone and board.
It is not stainless. A 26C3 blade will react to moisture and acidic ingredients, developing a patina that changes with use. It should be washed by hand, dried promptly and never left wet on the board.
For some cooks, that is an inconvenience. For others, it is part of the appeal: a fine carbon edge and a surface that records the life of the knife.
The Birch & Bevel Modern Spicy White Mono uses 26C3 as a single steel, without cladding between the cook and the carbon. It is the most accessible knife in the Birch & Bevel programme and the most direct expression of its carbon-steel performance.
Sandvik, Alleima and the Swedish stainless family
A separate Swedish tradition developed around Sandviken.
Göran Fredrik Göransson was one of the first people to make the Bessemer process work successfully on an industrial scale. He founded Sandvikens Jernverk in 1862, establishing the company that became Sandvik. Its materials division later operated as Sandvik Materials Technology before becoming the independent company Alleima in 2022.
The names have changed, but the continuity matters. Sandvik and now Alleima have developed a family of stainless knife steels centred on fine carbides, reliable industrial production and practical cutting performance.
Three grades help explain that progression.
12C27 became one of the archetypal Swedish stainless cutlery steels: balanced, corrosion-resistant and capable of taking a fine edge.
13C26 moved further toward razor performance. It is closely related in purpose and composition to AEB-L, although it belongs to the Sandvik lineage rather than Uddeholm’s.
14C28N represents a more recent refinement of the idea. Its chemistry includes approximately 0.62% carbon, 14% chromium and a deliberate nitrogen addition. Alleima recommends it for applications that place high demands on sharpness, edge stability and corrosion resistance, including chef’s knives.
The nitrogen helps the steel achieve excellent corrosion resistance without sacrificing the fine microstructure that makes it comparatively easy to sharpen. Alleima reports an average carbide size of approximately 0.5 microns across its fine-carbide stainless family, allowing these steels to support very acute edges without the interruption caused by large primary carbides.
For the cook, 14C28N occupies a particularly useful position:
- More forgiving than many high-wear powder steels
- Highly resistant to corrosion
- Tough enough for thin kitchen geometry
- Capable of a refined edge
- Straightforward to sharpen and maintain
It is not the most expensive or exotic alloy available. That is precisely why it deserves attention. Like AEB-L, it shows how good steel design is often an exercise in restraint rather than accumulation.
When 14C28N appears in the Modern Cooking collection, it belongs to this larger history: generations of Swedish strip steel developed around the practical requirements of sharp, durable blades.
Söderfors and the road to powder metallurgy
Söderfors sits in northern Uppland, and steel has shaped the community for more than three centuries. Anchor production began there in 1676. Anchors required large, dependable forgings in which hidden defects could have severe consequences, reinforcing an early concern with material integrity.
By the twentieth century, the region’s steel industry had moved into advanced alloys and powder metallurgy. The Söderfors operations now associated with Erasteel have continued to develop gas atomisation, powder processing, consolidation, forging and rolling.
Powder metallurgy is sometimes treated as a badge of quality by itself, but its value depends on the problem being solved.
A conventional steel ingot cools relatively slowly. In a highly alloyed composition, that can allow carbides to grow large or segregate unevenly. During gas atomisation, molten steel is broken into small droplets that solidify rapidly. This restricts carbide growth and preserves a more even distribution of alloying elements.
Erasteel’s powder-metallurgy production route, from molten steel and gas atomisation to hot isostatic pressing. Graphic courtesy of Erasteel. Source: Cutting Tool Applications Guide.
The resulting powder is not yet a blade steel. It must be placed in a container, consolidated under heat and pressure, forged and rolled into usable material. Done properly, the process allows alloy-rich steels to retain a fine, homogeneous structure that would be difficult to achieve through conventional casting alone.
RWL34 is one of the most important knife steels to emerge from that tradition.
RWL34: a Swedish powder-steel interpretation of ATS-34
RWL34 begins with ATS-34, the Japanese stainless steel favoured by American knifemaker Robert Waldorf Loveless. Loveless valued ATS-34 because it offered the hardness, edge retention and corrosion resistance he wanted in a working knife at a time when relatively few stainless steels met the expectations of custom makers.
Pelle Billgren approached the same alloy concept through Sweden’s developing expertise in powder metallurgy. Instead of casting the steel as a conventional ingot, the molten alloy was gas-atomised into rapidly solidified powder and then consolidated into solid material. This produced a cleaner, more evenly distributed structure than the conventional form of the alloy. The resulting steel was named RWL34 in honour of Loveless.
Its nominal composition—approximately 1.05% carbon, 14% chromium, 4% molybdenum and 0.2% vanadium—remains closely related to ATS-34. The difference lies principally in how the material is produced. Powder metallurgy allows that relatively rich alloy to retain fine, evenly distributed carbides, supporting a stable edge while preserving the corrosion resistance and wear performance for which the composition was chosen.
For a cook, RWL34 offers:
- Excellent corrosion resistance
- Dependable edge retention
- Good strength and toughness
- A refined, stable cutting edge
- Clean sharpening for a powder stainless steel
- The ability to take an exceptional polish
RWL34 is frequently encountered as one of the steels inside patterned Damasteel, but it is equally compelling without a pattern.
The Birch & Bevel Modern RWL Mono is forged entirely from RWL34. It is designed for the cook who wants a handmade Swedish-steel knife without managing carbon-steel reactivity. There is no cladding and no etched pattern—the material earns its place through performance and low-maintenance utility.
How Swedish powder became Damasteel
Pattern welding usually involves joining different steels and manipulating the billet so that their boundaries become a pattern. The method is ancient, but stainless steels present a particular challenge.
Chromium gives stainless steel its corrosion resistance by forming a protective oxide at the surface. That same oxide can prevent a clean forge weld. Producing stainless patterned steel reliably therefore requires much tighter control over oxygen, temperature and the surfaces being joined.
In 1992, Pelle Billgren, then working with powder materials at Erasteel, began collaborating with Swedish bladesmith Kaj Embretsen. Together they developed a method for producing high-alloy patterned steel through powder metallurgy. Their work received the Innovation of the Year award at the 1994 European Powder Metallurgy Association conference, and Damasteel followed.
The process brought together two bodies of knowledge: Söderfors powder metallurgy and a bladesmith’s understanding of how steel must move beneath a hammer.
Damasteel’s DS93X martensitic stainless patterned steel combines two powder alloys: RWL34 and PMC27. Both are hardenable stainless knife steels. RWL34 contains approximately 1.05% carbon together with 4% molybdenum, while PMC27 begins with approximately 0.60% carbon and no significant molybdenum.
The powders are arranged in layers inside a canister, the air is removed, and the material is consolidated under heat and pressure before being forged and patterned. This controlled, oxygen-excluding route is an important distinction from conventional Damascus made by forge-welding stacked solid sheets.
Something particularly interesting happens during the high-temperature consolidation and forging. Carbon is a small, mobile element, and it diffuses across the boundaries between RWL34 and PMC27. The two layers do not become chemically identical, but their carbon content moves closer to equilibrium, allowing the finished composite to respond to heat treatment more coherently than the starting compositions alone might suggest.
The larger alloying elements move much more slowly. Enough molybdenum and chromium difference remains between the layers to preserve their individual response to etching. RWL34 stays bright and reflective; PMC27 etches darker and more matte. The steels therefore become more closely aligned in their hardening behaviour without losing the alloy contrast that makes the pattern visible.
Carbon diffusion itself is not exclusive to Damasteel—it can also occur in conventionally forge-welded billets. What distinguishes DS93X is the combination of powdered starting materials, controlled consolidation and two closely specified functional knife steels. It is neither a pattern printed onto the surface nor decorative cladding over an unrelated core. The pattern runs through the blade, and both constituent steels participate in its cutting performance.
From Björkmans Twist to Odins Eye
Damasteel’s pattern library gives makers a material vocabulary rather than a single appearance.
Twisted patterns such as Dense Twist and Heimskringla create movement by rotating the layered billet. Coined patterns such as Odins Eye, Ladder and Rose reorganise the material into more graphic repetitions. Other designs—including Hakkapella, Hugin, Thor, Baldur and Yggdrasil—offer different scales, directions and densities.
Björkmans Twist is especially distinctive. It was named after a Swedish bladesmith who wanted a more intense version of Dense Twist. The result has a tight, organic grain that can resemble figured timber more than the regular stripes often associated with Damascus steel.
Damasteel states that no two pieces are identical. The pattern is produced within the billet, but the finished blade still belongs to the maker: orientation, forging, profile, bevel geometry, grinding and etching all influence how the material is ultimately revealed.
Björkmans Twist and MCx Johnsson × Krichbaum
Björkmans Twist is the steel around which the MCx Johnsson × Krichbaum series was built.
The series brings together Swedish bladesmith Jonas Johnsson of Isasmedjan, Austrian maker Simon Krichbaum and the MCx studio. The division of work is determined by the needs of each edition rather than imposed as a permanent production formula.
For Edition 01, Johnsson forged and heat-treated the blades, then made and fitted the stacked birchbark and stainless takedown handles. Krichbaum ground and finished the blades. The rokkaku hanmaru handle form and the tight, organic movement of Björkmans Twist gave the edition its visual identity, but its character came equally from the sequence of decisions shared between the two workshops.
Future editions may divide the work differently as new blade designs are developed. That flexibility is part of the collaboration: each maker contributes where their skills best serve the particular knife rather than repeating the same allocation of tasks for every release.
This is the role MCx is intended to play—not placing a logo over a maker’s work, but creating the conditions for distinct makers, materials and ideas to meet.
Which Swedish knife steel should you choose?
These steels share a national tradition, but they suit different cooks.
| Steel | Character | Best suited to |
|---|---|---|
| 26C3 | Reactive carbon steel, extremely keen and quick to sharpen | Cooks who enjoy carbon steel, patina and sharpening |
| AEB-L | Tough, fine-carbide stainless with excellent edge stability | Cooks wanting thin geometry and easy stainless maintenance |
| 14C28N | Fine-carbide nitrogen stainless balancing toughness and corrosion resistance | Everyday users wanting a forgiving, practical stainless knife |
| RWL34 | Powder-metallurgy stainless with stronger wear resistance and polishability | Busy kitchens wanting premium stainless performance |
| DS93X Damasteel | Functional stainless patterned steel built from RWL34 and PMC27 | Cooks and collectors wanting performance with a unique material expression |
This comparison is a starting point, not a final ranking. Steel composition establishes possibilities. Heat treatment controls hardness and structure. Geometry determines how the knife meets the food. The maker must bring all three together.
A superb AEB-L knife can outperform an indifferent powder-steel knife. A thin 26C3 edge may feel extraordinary in vegetables but demand more care. RWL34 may be the better tool in a kitchen where a reactive blade would become a burden.
The right choice is the steel whose strengths match both the maker’s intentions and the way you actually cook.
What the Swedish steel tradition amounts to
There is no single secret behind Swedish knife steel.
Its reputation began with exceptionally pure ore and the disciplined refining practices developed around it. It grew through Walloon ironmaking, dependable forgings and industrial steel production. It was sharpened by the demands of razor and scalpel strip, extended through Sandvik’s fine-carbide stainless steels and transformed again through powder metallurgy in Söderfors.
AEB-L, 14C28N, 26C3, RWL34 and Damasteel are not variations of one material. They are different answers to the same enduring question: how do you make steel clean, consistent and fine enough to support a truly good edge?
Our relationship with these steels begins with performance, but it does not end there. We are interested in what happens when makers interpret a material through their own approach to heat treatment, geometry and handwork. In Birch & Bevel, 26C3 and RWL34 become two direct mono-steel expressions of the same gyuto. Elsewhere in the collection, AEB-L, 14C28N and other Swedish steels take on different characters in the hands of makers working across distinct traditions and regions. In MCx Johnsson × Krichbaum, Damasteel’s Björkmans Twist becomes the common material around which two makers and the MCx studio develop a knife whose pattern, construction and performance could not belong to either workshop alone.
The steel brings history and potential. The knife reveals what the maker has done with it.
Further viewing
For a closer look at the processes behind these steels, blacksmith Alec Steele has filmed two excellent visits to Sweden: How Super Steels Are Made, exploring powder-steel production at Erasteel, and How Stainless Damascus Is Made, following the production of patterned stainless steel at Damasteel. Together, they provide a rare view inside the mills and workshops behind the materials discussed here.
Sources
- Jernkontoret — The history of the Swedish iron and steel industry
- Uddeholmstrip — Razor and scalpel steel
- Alleima — History
- Alleima — 14C28N knife steel
- Erasteel — History
- Erasteel — Cutting Tool Applications Guide
- Damasteel — The story of Damasteel
- Damasteel — The process of making Damasteel
- Damasteel — The story of RWL34
- Damasteel — Björkmans Twist
- Knife Steel Nerds — Damasteel heat treatment and properties