About 308Si Sub Arc Wire

The 308Si sub arc wire is a stainless steel welding wire containing silicon (Si), enhancing fluidity and penetration. It’s commonly used in submerged arc welding processes for joining austenitic stainless steels, providing excellent corrosion resistance and mechanical properties in various applications such as pressure vessels and pipelines.

308Si Sub Arc Wire Chemical Compositions:

The chemical composition of 308Si sub arc wire typically includes:

  • Carbon (C): ≤ 0.08%
  • Silicon (Si): 0.30 – 0.65%
  • Manganese (Mn): 1.00 – 2.50%
  • Phosphorus (P): ≤ 0.040%
  • Sulfur (S): ≤ 0.030%
  • Chromium (Cr): 18.0 – 21.0%
  • Nickel (Ni): 9.0 – 11.0%
  • Molybdenum (Mo): ≤ 0.75%
  • Iron (Fe): Balance

These elements contribute to the wire’s weldability, corrosion resistance, and mechanical properties.

308Si Sub Arc Wire Physical Properties:

The physical properties of 308Si sub arc wire include:

  1. Density: Typically around 7.9 g/cm³, similar to other austenitic stainless steels.
  2. Melting Point: Approximately 1400-1450°C (2552-2642°F), suitable for high-temperature welding applications.
  3. Thermal Conductivity: Moderate thermal conductivity, aiding in efficient heat transfer during welding.
  4. Electrical Conductivity: Good electrical conductivity, useful in certain electrical applications.
  5. Magnetic Properties: Non-magnetic in the annealed condition, becoming slightly magnetic after welding due to martensitic transformation.
  6. Coefficient of Thermal Expansion: Similar to other austenitic stainless steels, minimizing distortion during welding.
  7. Hardness: Varies depending on heat treatment, typically around 150-200 HV (Vickers hardness), providing good strength and wear resistance.

308Si Sub Arc Wire Mechanical Properties:

The mechanical properties of 308Si sub arc wire typically include:

  1. Tensile Strength: Typically 550-750 MPa, providing strong resistance to breaking under tension.
  2. Yield Strength: Approximately 240-320 MPa, indicating the stress at which the material begins to deform plastically.
  3. Elongation: Around 30-40%, demonstrating good ductility and the ability to stretch without fracturing.
  4. Hardness: Typically in the range of 180-220 HB (Brinell hardness), balancing toughness and machinability.
  5. Impact Resistance: Good impact resistance, suitable for applications subjected to sudden forces or shocks.
  6. Fatigue Strength: High resistance to cyclic loading, crucial for components experiencing repeated stress.
  7. Weldability: Excellent weldability with minimal risk of cracking or defects, ensuring reliable joint strength and integrity.

308Si Sub Arc Wire Applications:

The 308Si sub arc wire finds various applications due to its properties:

  1. Pressure Vessels: Used in the fabrication of pressure vessels for industries like oil and gas.
  2. Pipelines: Ideal for welding pipelines where corrosion resistance is essential.
  3. Boilers: Employed in the construction and repair of boilers in power plants and industrial facilities.
  4. Chemical Processing Equipment: Suitable for welding components in chemical processing plants.
  5. Food Processing: Used in food processing equipment due to its corrosion resistance and cleanliness.
  6. Aerospace: Utilized in aerospace applications requiring high-quality welds and corrosion resistance.
  7. Automotive: Used in automotive manufacturing for components requiring high strength and corrosion resistance, such as exhaust systems.