What is the difference between these steels AISI 1008 and AISI 1080?

 Answer: AISI 1008 and AISI 1080 are both carbon steels, but they differ significantly in their chemical composition, mechanical properties, and applications due to their carbon content and alloying elements. Below is a detailed comparison based on standard metallurgical data and general knowledge of steel properties, tailored to provide a clear and concise understanding.

1. Chemical Composition

• AISI 1008:
  • Carbon (C): 0.10% max
  • Manganese (Mn): 0.30–0.50%
  • Phosphorus (P): 0.040% max
  • Sulfur (S): 0.050% max
  • Iron (Fe): Balance
  • Characteristics: Low-carbon steel with minimal alloying elements, making it soft, ductile, and easy to form.
• AISI 1080:
  • Carbon (C): 0.75–0.88%
  • Manganese (Mn): 0.60–0.90%
  • Phosphorus (P): 0.040% max
  • Sulfur (S): 0.050% max
  • Iron (Fe): Balance
  • Characteristics: High-carbon steel with higher carbon and manganese content, increasing hardness and strength but reducing ductility.

2. Mechanical Properties

• AISI 1008:
  • Tensile Strength: ~340 MPa (49 ksi)
  • Yield Strength: ~210 MPa (30 ksi)
  • Elongation: ~45% (high ductility)
  • Hardness: ~95 HRB (soft, easily formed)
  • Characteristics: Excellent formability and weldability due to low carbon content. Suitable for cold forming, bending, and drawing. Limited strength and wear resistance.
• AISI 1080:
  • Tensile Strength: ~770–930 MPa (112–135 ksi, depending on heat treatment)
  • Yield Strength: ~440–620 MPa (64–90 ksi)
  • Elongation: ~10–12% (lower ductility)
  • Hardness: ~229 HB (as-rolled; higher with heat treatment)
  • Characteristics: High strength and hardness, especially after heat treatment (e.g., quenching and tempering). Less ductile, prone to cracking during forming.

3. Applications

• AISI 1008:
  • Automotive body panels, fenders, and brackets
  • Sheet metal for enclosures and appliances
  • Welded tubing and wire products
  • Used in applications requiring high formability, such as:
  • Ideal for processes like deep drawing, bending, and stamping, as seen in Metal Stamping Atlas’s Processes
• AISI 1080:
  • Cutting tools, knives, and blades
  • Springs and high-strength wires
  • Agricultural tools and machinery components
  • Suited for high-strength, wear-resistant applications, such as:
  • Often heat-treated to enhance hardness for demanding environments.

4. Processing Characteristics

• AISI 1008:
  • Formability: Excellent for cold forming due to low carbon content, which reduces work hardening.
  • Weldability: Superior weldability with minimal risk of cracking, suitable for MIG, TIG, and resistance welding.
  • Machinability: Moderate; softer material can lead to gummy chips during machining.
• AISI 1080:
  • Formability: Limited due to high carbon content, which makes it brittle and prone to cracking during bending or forming unless annealed.
  • Weldability: Poor; high carbon content increases the risk of cracking during welding, requiring preheating and post-weld heat treatment.
  • Machinability: Better than 1008 when annealed, but hardened 1080 is challenging to machine.

5. Heat Treatment Response

• AISI 1008:
  • Limited response to heat treatment due to low carbon content. Can be case-hardened (e.g., carburizing) to increase surface hardness but not suitable for through-hardening.
  • Typically used in the annealed or as-rolled condition.
• AISI 1080:
  • Excellent response to heat treatment, such as quenching and tempering, achieving high hardness (up to 60 HRC) and strength.
  • Commonly used in hardened or tempered states for tools and springs.

6. Cost and Availability

• AISI 1008: Generally less expensive due to lower carbon and alloy content. Widely available as sheet, strip, or wire for stamping and forming applications.
• AISI 1080: More costly due to higher carbon content and processing requirements (e.g., heat treatment). Available in bars, rods, or sheets for specialized applications.

7. Key Differences Summary

Property	AISI 1008	AISI 1080
Carbon Content	Low (0.10% max)	High (0.75–0.88%)
Strength	Low to moderate	High (especially after heat treatment)
Ductility	High (excellent formability)	Low (brittle, limited formability)
Weldability	Excellent	Poor (requires special care)
Applications	Automotive panels, enclosures	Tools, springs, high-strength parts
Heat Treatment	Limited (case-hardening)	Excellent (through-hardening)

AISI 1008 is a low-carbon steel ideal for applications requiring formability and weldability, such as automotive panels and stamped components. AISI 1080, a high-carbon steel, offers superior strength and hardness for tools and springs but sacrifices ductility and weldability. The choice between them depends on the application’s demands—1008 for flexible, cost-effective forming, and 1080 for high-performance, durable components. For custom metal stamping solutions.