Yaxell KETU

Yaxell KETU

Yaxell Ketu - SG2 powder steel at its finest

The Ketu series ranks among the very top of the Yaxell range. The series kanji is pronounced "kyoshi" and means "unblemished" or "pure" - a reference both to the purity of the powder steel used and to the refinement of the finish. Where Yaxell's VG10 series represent the established standard, the Ketu steps up to a more advanced core steel: SG2 powder metallurgy steel, one of the highest-performing knife steels in the world.

Yaxell Corporation was founded in 1932 in Seki, the city in Gifu Prefecture that has been the centre of Japanese knife and sword making tradition for over 780 years. The Ketu unites that centuries-old forging tradition with the most modern steel technology: a hand-hammered Damascus surface around a core of advanced sintered powder steel.

The steel: SG2 powder steel in San Mai construction

The Ketu blade has a SG2 powder steel core clad on both sides with a layer of softer stainless steel - a 3-layer San Mai construction. The softer outer layers protect the hard but naturally more brittle core from breaking and absorb shocks during use.

What is SG2 powder steel?

SG2 (also known as SGPS, "Super Gold Powder Steel", or R2) is a high-quality stainless steel produced through powder metallurgy rather than traditional casting. In this process the steel is first atomised into a fine powder and then compressed under high pressure and temperature (sintered). The result is an exceptionally fine, uniform grain structure with evenly distributed carbides - far finer and more regular than is possible with conventionally cast steel.

That fine microstructure is precisely what makes SG2 special. The steel can take an extremely sharp, fine cutting edge and hold it longer than virtually any conventional steel, while the even carbide distribution reduces micro-chipping under lateral stress. SG2 is therefore often described as a "laser": knives that glide through ingredients with minimal resistance and retain their sharpness exceptionally long.

Composition and properties

• Carbon (C: approx. 1.4%) - Considerably higher than VG10 (approx. 1.0%). The high carbon content is the basis of the high hardness and excellent edge retention.
• Chromium (Cr: approx. 15-16%) - Well above the threshold for stainless steel. Delivers excellent corrosion resistance despite the high carbon content.
• Molybdenum (Mo: approx. 3%) - Considerably higher than in VG10. Increases hardness, wear resistance and resistance to pitting corrosion.
• Vanadium (V: approx. 2%) - Much higher than VG10 (approx. 0.3%). Vanadium forms extremely hard carbides that greatly improve wear resistance and edge retention, and further refines the grain structure.
• Hardness: 63 HRC - Higher than the VG10 series (61 HRC) and considerably higher than European stainless steel (approx. 58 HRC). This high hardness delivers longer edge retention and enables a finer, thinner cutting edge.
• Edge angle: 16 degrees per side - Sharper than European chef's knives (20-22 degrees per side), giving a finer and cleaner cut.

SG2 and sharpening

The high hardness and high carbide content mean SG2 holds its cutting edge exceptionally long - noticeably longer than VG10. The trade-off: when the knife eventually does need sharpening, the harder steel requires good whetstones and correct technique. An investment that pays off in rare sharpening sessions and consistent sharpness.

The finish: hand-hammered Damascus

The outer layers of the Ketu blade feature a hand-hammered Damascus surface. The hammered pattern (in Japanese tsuchime) consists of shallow dimples hammered by hand into the blade. This finish serves a dual purpose: aesthetically it gives the blade a lively, artisanal surface that catches the light, and functionally the dimples create small air pockets between the food and the blade, so moist ingredients (such as potato, cucumber or fish) stick less and release more easily from the blade.

The handle: curved beechwood Pakka

The Ketu handle is made from black beechwood Pakka with a gently curved shape for a natural, comfortable grip. Pakka is a composite material of laminated wood and synthetic resin: it combines the warm appearance of wood with the moisture resistance and dimensional stability of a synthetic material. It is non-porous and resistant to temperature and humidity changes.

The curved handle shape visually distinguishes the Ketu from the straighter handles of other Yaxell series and fits the hand ergonomically. The handle features the engraved Ketu kanji and the emblem of the Japanese samurai tradition. Two stainless steel bolsters join the blade to the handle, reinforced with a stainless steel rivet. The bolster clearly separates the handle from the blade, providing extra safety while cutting.

Care

• ✅ Hand-wash immediately after use. Never in the dishwasher. Avoid wetting the handle as much as possible.
• ✅ Dry immediately after washing with a clean, dry cloth.
• ✅ Use a wooden or plastic cutting board. Stone, glass and ceramic damage the cutting edge.
• ✅ Do not use an abrasive sponge. It damages both the hammered finish and the handle.
• ✅ Sharpen on a good whetstone (1000-3000 grit for maintenance, 6000+ for finishing). The hard SG2 steel requires quality whetstones and correct technique; honing steels and pull-through sharpeners are not suitable.
• ✅ Store on a knife block or magnetic strip.
• ⚠️ Not for chopping hard bones or frozen products. At 63 HRC, SG2 is exceptionally hard and sharp, but therefore also more susceptible to chipping under lateral forces or hard impacts.

Specifications

• Manufacturer: Yaxell Corporation, Seki, Japan (founded 1932)
• Construction: San Mai, 3 layers (SG2 core + stainless outer layers)
• Core steel: SG2 powder steel (also known as SGPS / R2)
• Hardness: 63 HRC
• Edge angle: 16 degrees per side
• Grind: Double bevel (50/50)
• Finish: Hand-hammered Damascus (tsuchime)
• Handle: Curved black beechwood Pakka
• Fastening: Two stainless steel bolsters, stainless steel rivet
• Origin: Seki, Japan