DIN 1.1191

DIN 1.1191 steel is a medium carbon steel characterized by good machinability, toughness, and strength. It is widely used in various industrial applications due to its versatility and affordability. 

Composition:

- Carbon (C): 0.42 - 0.50%

- Silicon (Si): 0.15 - 0.40%

- Manganese (Mn): 0.50 - 0.80%

- Phosphorus (P): ≤ 0.025%

- Sulfur (S): ≤ 0.025%

Properties:

- Hardness: Typically around 170-210 HB (Brinell hardness)

- Density: ~7.85 g/cm³

- Tensile Strength: 570-700 MPa (82,000-101,000 psi)

- Yield Strength: ~300-450 MPa (43,500-65,300 psi)

- Elongation: ~14-22% (in 50 mm)

Heat Treatment:

- Annealing: Heat to 650-700°C (1202-1292°F), hold until uniform temperature is reached, furnace cool at a rate not exceeding 10°C (18°F) per hour.

- Normalizing: Heat to 850-890°C (1562-1634°F), hold until uniform temperature is reached, air cool.

- Hardening: Heat to 820-860°C (1508-1580°F), quench in water or oil.

- Tempering: Temper immediately after hardening. Typical tempering temperature ranges from 550-660°C (1022-1220°F) for desired hardness and toughness.

Applications:

- 1191 steel is commonly used for making gears, shafts, axles, bolts, studs, and hydraulic cylinders.

- It is suitable for components that require good mechanical properties and wear resistance without high stress.

 Machinability:

- 1191 steel has good machinability in the normalized or hot rolled condition. It responds well to machining operations such as drilling, milling, turning, etc.

 Weldability:

- 1191 steel has moderate weldability. It can be welded using all conventional welding methods without preheating, although preheating might be required for thick sections or heavy weldments.

Corrosion Resistance:

- 1191 steel is not corrosion resistant and should be protected against corrosion. It can rust if exposed to moisture and atmospheric conditions.

1191 steel is a widely used medium carbon steel with good mechanical properties and cost-effectiveness, making it suitable for a variety of applications in different industrial sectors. Its balance of strength, hardness, and machinability makes it a versatile choice for manufacturing components and parts where moderate strength and toughness are required.