1. Key Properties:
Good Strength: SAE 1018-1020 steel offers moderate tensile strength, making it suitable for a wide range of structural and mechanical applications.
Excellent Weldability: These steels are highly weldable, ideal for fabrication and manufacturing processes that require strong, reliable joints.
Machinability: SAE 1018-1020 provides good machinability, making it easy to cut, drill, and shape into precise components.
Formability: Both grades offer excellent formability, allowing for easy shaping and bending.
Corrosion Resistance: While not highly resistant to corrosion, it is well-suited for use in environments that are not exposed to harsh conditions.
Ductility: Offers good ductility, ensuring it can withstand deformation without breaking, which is essential for parts that require some flexibility.
2. Applications/Industries:
Automotive: Used in the manufacture of components like shafts, gears, axles, and other parts that require moderate strength and good formability.
Machinery Manufacturing: Ideal for producing machinery parts, including rods, bars, and other structural components that are subject to moderate stresses.
Construction: Commonly used in structural applications such as bolts, pins, and other parts that need good strength but don’t require extreme hardness.
Oil & Gas: Used in less demanding applications in oil and gas machinery, including some pipeline components and non-critical structural parts.
Aerospace: Utilized for producing non-critical parts of aerospace equipment due to its moderate strength and machinability.
General Engineering: Great for producing a wide range of mechanical components where moderate strength and ease of fabrication are important.
3. Certifications/Standards:
ASTM A29: SAE 1018 and 1020 meet the standards outlined in ASTM A29 for cold-finished carbon steel bars.
ASTM A108: For SAE 1018 and 1020, this standard governs cold-finished carbon steel bars, ensuring they meet specific mechanical and chemical properties.
ISO 9001: Certification for quality management systems (depending on manufacturer).
SAE J403: Specifies the requirements for carbon steel grades, including 1018 and 1020.
DIN 17100: The grade complies with general structural steel standards, although SAE grades are more common in U.S. standards.
4. Chemical Composition:
SAE 1018:
Carbon (C): 0.18%
Manganese (Mn): 0.60% – 0.90%
Phosphorus (P): 0.04% max
Sulfur (S): 0.05% max
Iron (Fe): Balance
SAE 1020:
Carbon (C): 0.18% – 0.23%
Manganese (Mn): 0.30% – 0.60%
Phosphorus (P): 0.04% max
Sulfur (S): 0.05% max
Iron (Fe): Balance
Both grades offer a similar composition, with SAE 1020 having slightly higher carbon content compared to 1018, giving it slightly higher strength.
5. Technical Specifications:
Yield Strength:
SAE 1018: 280 MPa (minimum)
SAE 1020: 310 MPa (minimum)
Tensile Strength:
SAE 1018: 440–590 MPa
SAE 1020: 410–550 MPa
Hardness:
SAE 1018: Approximately 120–170 HB (Brinell hardness)
SAE 1020: Approximately 120–170 HB
These specifications reflect the steel's suitability for moderate-strength applications where ease of machining and fabrication are essential.