Steel Library/S390 Microclean
Powder Metallurgy Steel
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S390 Microclean

Heat Treatment Specifications

Austenitizing

Temperature1175°C(2147°F)
Soak Time2 minutes

Tempering

Temperature550°C(1022°F)
Time120 minutes
Cycles3x

Quench Medium

oil

Target Hardness

65 - 68 HRC

Performance Characteristics

Toughness6/10
Edge Retention9.5/10
Corrosion Resistance2.5/10
Ease of Sharpening3/10
Overall Score21/40

Interesting Facts

  • 1Böhler's flagship powder metallurgy HSS
  • 21.64% carbon, 4.8% vanadium, 10.5% tungsten, 2% cobalt
  • 3Among highest edge retention PM steels available
  • 467-70 HRC achievable - extremely hard
  • 5Very difficult to sharpen - diamond abrasives recommended
  • 6Tougher than Rex 121 despite similar wear resistance

Famous Uses

Ultra-premium custom knives
High-end industrial cutting

Best For

High-performance cutters
Heavy-duty knives
Professional tools

Similar Steels

Not Recommended For

  • Field sharpening (nightmare)
  • Impact loads
  • Budget

Expert Tips

  • 1Red-hot hardness
  • 268 HRC tested success
  • 33-5 micron carbides
  • 4Versatile heat treatment

Track Your S390 Microclean Heat Treats

Start logging your heat treatment cycles with S390 Microclean. Track what works, compare results, and repeat your best blades.

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