Stainless Steel
Beginner Friendly
Mid-range

N690

Heat Treatment Specifications

Austenitizing

Temperature1060°C(1940°F)
Soak Time10 minutes

Tempering

Temperature150°C(302°F)
Time120 minutes
Cycles2x

Quench Medium

oil

Target Hardness

59 - 60 HRC

Performance Characteristics

Toughness5/10
Edge Retention5.5/10
Corrosion Resistance7.5/10
Ease of Sharpening6.5/10
Overall Score24.5/40

Interesting Facts

  • 1Introduced by Bohler in 1998 as evolution of 440B
  • 2In 1998, pilot melts sent to Austrian, Italian, German knifemakers
  • 3Selected for French Army field knife to demanding specifications
  • 4Popular for dive knives due to pitting resistance in salt water
  • 5GiantMouse, Halfbreed Blades, Midgards Messer use it today
  • 6Formula stable since 1998 - data sheets identical to 2025

Famous Uses

Extrema Ratio
Fox Knives
French Army field knife
LionSteel

Best For

Knife blades requiring corrosion resistance
General purpose cutting

Similar Steels

Not Recommended For

  • Extreme wear resistance
  • Premium segment (mid-level)
  • Heavy work

Expert Tips

  • 1Good carbide former due to chromium and molybdenum
  • 2Cobalt enhances attainable hardness

Track Your N690 Heat Treats

Start logging your heat treatment cycles with N690. Track what works, compare results, and repeat your best blades.

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