Heat Treatment Specifications
Austenitizing
Temperature780°C(1436°F)
Soak Time10 minutes
Tempering
Temperature180°C(356°F)
Time60 minutes
Cycles1x
Quench Medium
water
Target Hardness
58 - 60 HRC
Performance Characteristics
Toughness6.5/10
Edge Retention6.5/10
Corrosion Resistance0.5/10
Ease of Sharpening8.5/10
Overall Score22/40
Interesting Facts
- 1~0.95% carbon - middle of SK range
- 2Better edge retention than SK5 due to higher carbon
- 3SK5 provides better toughness, SK4 holds edge longer
- 4Common in Japanese industrial blade production
Famous Uses
Japanese razors
Utility knives
Hand tools
Best For
Traditional Japanese tools
Chisels
Specialized cutting
Similar Steels
SK5
Slightly softer, more popular
Shirogami #2
Premium version
Not Recommended For
- Wet environments
- Western markets
Expert Tips
- 1High carbon content
- 2Minimal chromium
- 3Excellent edge holding
- 4Rust prone - needs care