A588 Corten Steel is widely used in structural and architectural applications due to its high strength and exceptional resistance to atmospheric corrosion.
However, welding A588 Corten Steel requires special attention to ensure the structural integrity and corrosion performance of the final product.
Key factors include preheat treatment, appropriate filler metal selection, post-weld cleaning, and understanding common welding challenges.
Preheating Before Welding
Preheating is especially important when welding A588 Corten Steel plate in thick sections or when ambient temperatures are low.
Preheating helps prevent cold cracking and minimizes thermal shock in the heat-affected zone (HAZ).
For material thicknesses over 1 inch, a preheat temperature of 100–200°C (212–392°F) is often recommended.
Uniform heating across the weld area reduces the risk of uneven shrinkage and micro-cracks.
Welding Consumables and Filler Metals
When welding A588 Corten Steel, it is critical to use compatible low-alloy filler metals that promote similar corrosion resistance and mechanical properties. Commonly used filler metals include:
- AWS E8018-W or E7018 (low-hydrogen electrodes)
- ER80S-G (for GMAW/MIG processes)
- Corten specific filler wires (matching weathering characteristics)
- Using standard carbon steel filler wires may compromise the weld area's weathering resistance, causing premature rusting at the joints.
Welding Techniques and Best Practices
A588 Corten Steel can be welded using most conventional methods such as SMAW, GMAW, FCAW, and GTAW.
However, proper joint design and preparation are vital to ensure strong, durable welds.
For multi-pass welds, interpass temperature control is also important to avoid thermal fatigue.
When welding dissimilar steels, such as joining A588 Corten Steel to mild steel, special considerations must be made.
In these cases, corrosion resistance at the joint may be reduced, so protective coatings or sealing may be necessary.
Post-Weld Cleaning and Treatment
After welding, the weld zone should be cleaned of slag, splatter, and any surface impurities to allow the natural weathering process to continue uniformly.
If the welded structure is to be left unpainted, proper cleaning ensures that the rust patina develops evenly over time.
In some cases, post-weld heat treatment (PWHT) may be performed, especially for critical structural applications, to relieve residual stress
and enhance toughness in the weld zone.
Common Welding Challenges
Undermatching corrosion resistance: Caused by improper filler selection.
Cracking in the heat-affected zone (HAZ): Often due to insufficient preheating.
Color mismatch or patina inconsistency: From contaminants or incompatible welding processes.
Conclusion
Proper welding of A588 Corten Steel is essential for maintaining its corrosion resistance and mechanical performance. By using appropriate preheating, filler metals, and cleaning procedures, fabricators can ensure strong, weather-resistant welds that blend seamlessly with the base metal.
Whether you're working with A588 Corten Steel plate or coil, understanding these welding considerations ensures structural longevity and aesthetic consistency in any application.
