Yushoku Stainless: VG10W Stainless Steel Clad with Mokume (Copper, Brass, and Stainless Steel), DPS San Mai (.12" x 15-1/4" x 2")

Product Description for Yushoku Stainless: VG10W Stainless Steel Clad with Mokume (Copper, Brass, and Stainless Steel), DPS San Mai (.12" x 15-1/4" x 2")

Maker: Takefu Special Steel (click to see more by this maker)
Price: $370.37
Item num: 107415
Total length: 15.25 in.
Item weight: 17.00 oz.
Size: .12" x 15-1/4" x 2"
Description: This 3mm bar is laminated VG10W stainless steel with mokume cladding (forged from copper, brass and stainless steel). DPS (depletion prevention system) adds a thin nickel shim between the core steel and the cladding. The nickel acts as a barrier to stop carbon migration between the carbon steel core and mokume outer layers and creates a particularly dramatic and bold transition line. We recommend not upset forging this material as this can cause delamination.

The VG10W stainless steel core is made from pure iron material, resulting in ductility, workability and forgeability. VG10W is made by adding .4% tungsten (W) to VG10. Tungsten precipitates and disperses hard, fine carbides which contribute to improved wear resistance and ease of sharpening. Additionally, tungsten improves hardenability, reducing heat treatment temperatures. Compared to VG10, VG10W has 20% higher durability/strength and 25% higher cutting performance, while maintaining the same corrosion resistance. The addition of 1.55% of Cr provides corrosion resistance while 1% of Mo and 1.55% of Co makes a stronger matrix (substrate) and prevents carbides from dropping out of solution. By adding V, the grain structure becomes finer. Finer grain improves ease of sharpening. Added Cr, Mo, and V form many hard carbides, so abrasion resistance improves -- giving knives long-term edge holding for clean cutting. VG10W is very machinable and easy to grind.

VG-10W Specs
C CR Mo V W Co
1.0% 15.0% 1.0% 0.25% .4% 1.55%

Heat Treatment
Forging: Forge at 1010°C/1850°F. Do not heat over 1065°C/1950°F to avoid alloy separation. Do not forge below 900°C/1650°F. You should anneal (or sub-critical anneal) after forging.
Annealing: Anneal at 870°C/1598°F. Hold for 2 hours. Cooling speed should not exceed 25°C/hr - 77°F/hr to 900°F then air cool.
Sub-Critical Anneal (preferred by Mastersmith Bill Burke): Anneal at 1250°F. Hold for 2 hours. Let slow cool in oven.
Quenching: Quench at 1050-1065°C/1922-1950°F. Quench in oil (50°C/122°F) or air (25°C/77°F)
Tempering: Temper at 150-200°C (300-400°F).

Annealed: Hrc 25
Hardened: Hrc 59-60
Sub-Zero: Hrc 62-63

Mastersmith Bill Burke's Heat Treatment Recommendation: After forging/annealing, grind blade to 220 grit (120 grit minimum) finish. Wrap in high temp stainless foil, being sure to seal air tight. Place blade in heat treat oven and ramp oven to 1562°F (850°C) and hold 30 minutes. Ramp oven to 1922°F (1050°C) and hold for 15 minutes. Air, oil or plate quench. Use a slower oil such as Texaco Type A. This is resulting in Hrc 59-60 without sub-zero quench and Hrc 62-63 with a sub-zero quench. Air quench results in Hrc 59-60 at the time of heat treatment and then increases to Hrc 60-61 over the next 24-48 hours. Note that holding 15 minutes at austenizing temperature seems to be critical. Subzero quench at -112°F (60 minutes) to -300°F (30 minutes). Temper 2x for two hours each cycle for desired hardness at 300 - 400°F.

Yu-Shoku Stainless (VG10W) Heat Treatment Chart

Note: results may vary with hardening method and section size. Salt or oil quenching will give maximum results. Vacuum or atmosphere cooling may result in up to 1-2 Hrc lower.

Availability: In stock. Usually ships in 1-2 business days