Technical Specifications
Chemical Composition
- Carbon (C): 0.35–0.45%
- Silicon (Si): ≤ 1.00%
- Manganese (Mn): ≤ 1.50%
- Chromium (Cr): 1.80–2.00%
- Molybdenum (Mo): 0.15–0.25%
- Sulfur (S): 0.05–0.10%
- Phosphorus (P): ≤ 0.030%
Treatment
- Forging: Heat uniformly to 1050–850°C and cool slowly in the furnace after forging to relieve internal stresses.
- Annealing: Heat to 710–740°C, hold to equalize temperature, then cool slowly in the furnace to 550°C before air cooling.
- Hardening: Preheat to 850–900°C, then heat to 1000–1040°C and quench in oil or air depending on section size.
- Tempering: Temper immediately after hardening between 200–400°C depending on desired hardness. Air cool after tempering.
- Machinability: Enhanced due to sulfur addition, offering easy cutting and shaping ideal for pre-hardened tooling and mould bases.



