5160 (SUP9) Spring Steel Round Bar

5160 (SUP9) Spring Steel Round Bar

5160/SUP9 are spring steels with close to identical compositions and chemistry. They are deep hardening steels and are quenched in oil. When heat treated correctly They are perfect for big knives and swords, where performance and toughness really matter.

Allot Content

Carbon – 0.56-0.64%
Manganese – 0.75-1%
Chromium – 0.70%
Silicon – 0.15-0.30%
Phosphorus – <0.03%
Sulphur – <0.04%

Recommended Working Sequence

Forging:  815-1175°C – do not forge below 815°C

Normalizing: Heat to 870°C, cool to black in still air, follow up with refinement cycles at a lower temperatures

Annealing: Heat to 815°C, furnace cool to 650°C at a rate not exceeding 28°C per hour, or bury in an insulating material like vermiculite or wood ash

Grinding, Drilling, Machining

Recommended Heat Treatment

• Austenitise at 815°C until evenly heated – an extended soak time is not required, nor is heating the entire blade and tang i.e. just the edge can be heated
• Quench in oil pre-heated to 50-60°C – Fast Quench Oil.
• As quenched hardness 60-65HRC.
• Temper at 200°C for 2 hours, twice
• Tempered hardness at 200°C which should yeild ~59-60HRC