Tool Steel
Intermediate
Premium

INFI

Heat Treatment Specifications

Austenitizing

Data not available

Tempering

Data not available

Quench Medium

Check manufacturer recommendations

Target Hardness

58 - 60 HRC

Performance Characteristics

Toughness9/10
Edge Retention7/10
Corrosion Resistance4/10
Ease of Sharpening6/10
Overall Score26/40

Interesting Facts

  • 1Proprietary steel developed 2005 by Busse Combat
  • 2Jerry Busse started making knives in 1970s to pay for college
  • 3Hardened to 58-60 HRC but 'have yet to chip an edge'
  • 4Heat treatment takes 60+ hours with deep cryogenic treatment (-300F)
  • 5The 'magic' is the proprietary treatment process, not secret composition
  • 6Better salt spray test results than ATS-34 and D2
  • 7Original pre-2002 formula had nitrogen, post-2002 removed nitrogen and cobalt

Famous Uses

Busse Combat knives
Swamp Rat Knife Works

Best For

Combat and tactical fixed blades
Heavy-duty field use
Hard-use knives

Similar Steels

Not Recommended For

  • Budget
  • Fine cutting work
  • Kitchen

Expert Tips

  • 1Proprietary heat treatment protocol
  • 2Dense grain structure
  • 3Outstanding durability

Track Your INFI Heat Treats

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

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