Technical Specifications
Chemical Composition
- Carbon (C): 0.40–0.50% – Provides base strength and hardenability.
- Silicon (Si): 0.10–0.40% – Supports strength and deoxidation.
- Manganese (Mn): 0.20–0.50% – Enhances toughness and ductility.
- Chromium (Cr): 1.20–1.50% – Improves wear resistance and hardenability.
- Molybdenum (Mo): 0.15–0.35% – Boosts strength and temperature resistance.
- Nickel (Ni): 3.80–4.30% – Delivers high toughness and deep hardenability.
- Phosphorus (P): ≤ 0.03% – Keeps material clean and tough.
- Sulfur (S): ≤ 0.03% – Maintains machinability and quality.
Treatment
- Soft-Annealing: Heat to approx. 610-650 °C, hold and cool slowly in furnace to ~600 °C to achieve max ~260-285 HB for machining readiness.
- Hardening: Heat to around 840-870 °C (austenitising), then quench in oil or hot bath/air depending on section size to achieve full hardening.
- Tempering: Immediately after quenching, temper twice; e.g., temper to achieve hardness in range ~50-56 HRC depending on final use.
- Finish Machining & Polishing: Excellent polishability and dimensional control make it suitable for high-finish tools and moulds requiring mirror surfaces.



