TOKO AWS A5.4 E309L Welding Electrode

1. Chemical Composition

• Primary alloying elements:
• Chromium (Cr): ~23-25% (provides oxidation resistance).
• Nickel (Ni): ~12-14% (ensures austenitic structure and ductility).
• Carbon (C): ≤0.03% (minimizes sensitization in high-temperature environments).
• Minor elements may include manganese, silicon, and molybdenum in trace amounts (though 309L typically lacks significant molybdenum).

2. Mechanical Properties

• Tensile Strength: ~620 MPa (90 ksi).
• Elongation: ~35-40% (excellent ductility).
• Corrosion Resistance: Superior in high-temperature and oxidizing environments; resistant to intergranular corrosion due to low carbon.
• Non-magnetic: Austenitic structure ensures non-magnetic properties post-weld.
  

3. Applications

• Base Metals:
• Joining 309, 304, or 308 stainless steels.
• Dissimilar metal welding (e.g., stainless to carbon steel).
• Common Uses:
• High-temperature equipment (furnaces, exhaust systems).
• Cladding/overlaying carbon steel for corrosion resistance.
• Petrochemical, power generation, and food processing industries.

4. Operating Parameters

• Polarity: DC+ (direct current electrode positive).
• Preheat/Interpass Temp: Generally unnecessary for thin sections; maintain ≤150°C (300°F) for thick materials.
• Post-Weld Treatment: Stress relief annealing may be required for critical applications to restore corrosion resistance.
• Storage: Keep in dry conditions to prevent moisture pickup (low-hydrogen practice recommended).

5. TOKO-Specific Features

• Arc Stability: TOKO electrodes are known for smooth arc characteristics and minimal spatter.
• Slag Removal: Easy slag detachment improves weld efficiency.
• Certifications: Likely meets international standards (e.g., ISO, EN) for quality assurance.