1. Cutting Processes
Thermal Cutting (Plasma, Laser, Oxy-Fuel)
Preheating:
Not typically required for thin plates (<25mm), but for thicker sections (>30mm), preheat to 100–150°C to avoid cracking (especially in cold environments).
Exception: If the steel is in a quenched-and-tempered (Q&T) condition, consult the supplier for preheat guidelines.
Cutting Speed:
Slower speeds than carbon steel to ensure clean edges and minimize heat-affected zone (HAZ) brittleness.
Post-Cutting:
Remove slag and oxide residues to prevent contamination of the corrosion-resistant surface.
Mechanical Cutting (Shearing, Sawing)
Blade/Disc Selection:
Use hardened tool steel blades or carbide-tipped tools to withstand the steel's higher strength.
Lubricate blades to reduce wear.
Burr Removal:
Deburr edges to maintain corrosion resistance and safety.
2. Forming Processes (Bending, Rolling)
Cold Forming
Minimum Bend Radius:
≥2× plate thickness (e.g., 10mm plate → 20mm radius) to avoid cracking.
Thicker plates (>12mm) may require larger radii.
Springback Compensation:
S355J0WP has higher yield strength than mild steel; account for 10–15% more springback during die design.
Hot Forming (if needed)
Temperature Range:
900–1,100°C (avoid exceeding 1,200°C to prevent grain growth).
Post-Forming Cooling:
Air-cool naturally; rapid quenching may affect corrosion resistance.
3. Welding Considerations (Adjacent Processes)
Filler Material:
Use matching weathering steel electrodes (e.g., AWS E7018-W or EN ISO 2560-A).
Preheat/Interpass Temp:
100–150°C for thicknesses >15mm.
Post-Weld Cleaning:
Remove slag/spatter to allow uniform patina formation.
4. Surface Protection During Fabrication
Avoid Contamination:
Prevent contact with carbon steel tools/debris to avoid galvanic corrosion.
Temporary Coatings:
Use weathering-resistant primers if storing cut pieces outdoors before assembly.
5. Post-Processing for Corrosion Resistance
Patina Development:
After fabrication, expose steel to wet/dry cycles to accelerate protective rust layer formation.
Edge Treatment:
Seal cut edges with weathering-resistant paints if aesthetics are critical.
Key Standards Referenced
EN 10025-5: Covers technical delivery conditions for weathering steels.
ISO 9013: Guidelines for thermal cutting.
Summary of Special Requirements
| Process | Key Requirement | Reason |
|---|---|---|
| Cutting | Preheat thick sections; clean edges | Prevent HAZ cracks; maintain corrosion resistance |
| Bending | Larger bend radii vs. mild steel | Avoid cracking due to higher strength |
| Welding | Matching filler + preheat | Ensure weld metal matches base corrosion properties |
| Surface Care | Avoid carbon steel contamination | Prevent localized corrosion |
