1. Weldability
Q355NH weathering steel has good weldability and is widely used in welded steel structures.It is designed to allow common welding methods, similar to ordinary Q355B carbon steel.
2. Commonly used welding methods
Shielded metal arc welding (SMAW)
Gas metal arc welding (GMAW / MIG/MAG)
Submerged arc welding (SAW)
Gas tungsten arc welding (GTAW / TIG)
3. Matching welding materials
Weathering steel requires matching weathering-resistant welding electrodes / wires to ensure the weld zone has similar corrosion resistance and mechanical properties as the base metal.
Using ordinary carbon steel filler metal will reduce weathering performance in the weld area.
4. Key welding precautions
Control heat input to avoid excessive grain growth and reduced toughness.
Preheating is generally not required for thin to medium thickness under normal conditions.
For thick plates or low-temperature environments, proper preheating and interpass temperature control are recommended.
Avoid rapid cooling to prevent cold cracking.
Remove welding slag, spatter, and surface contaminants to maintain long-term corrosion resistance.
5. Performance of welded joints
Well-made welded joints can achieve stable strength and toughness matching the base metal.
With correct filler materials, the weld zone can form a protective patina and maintain weathering resistance.
