42CrMo4 4140 Alloy Steel Plate - 10-800mm Round Bar, 217 HBS Hardness, Black/Grinded/Machined Surface

High-quality alloy steel plate available in black surface, grinded, or machined finishes with excellent mechanical properties for demanding industrial applications.

• Round steel bar: 10-800mm diameter
• Flat steel bar: 10-400mm thickness × 200-2200mm width

Available in black surface, grinded, or machined finishes to meet specific application requirements.

Annealed hardness: HBS 217 maximum

• Excellent machinability in quenched and tempered condition
• High toughness and creep strength
• Superior repeated impact resistance
• Engineering-grade steel for demanding applications

• Gear wheels and pinions
• Connecting rods and mechanical components
• Parts for mechanical engineering requiring high toughness

• Forging: Heat to 1150°C, hold until uniform, minimum forging temperature 850°C, cool slowly
• Annealing: Heat to 830°C-850°C, cool in furnace
• Normalising: Heat to 870°C-900°C, cool in still air
• Stress Relieving: Annealed: 600°C-650°C; Hardened: 500°C-550°C; Cool in still air
• Hardening: Heat to 830°C-880°C, quench in oil or polymer
• Tempering: Heat to 450°C-700°C, cool in still air (avoid 200°C-420°C range)