Slag Inclusion
Massive slag inclusion is a large, continuous non-metallic residue in the weld metal. It interrupts the metallic structure and causes severe damage.
Physical-Chemical Mechanism of Action
Solid slag inclusion occurs when non-metallic materials such as dirt, impurities, or coating residues get into the weld metal. These substances remain in a liquid state and are not fully expelled during the welding process.
Metallurgical Relevance & Welding Risks
Solid slag inclusion causes severe defects in the weld metal. It can significantly impair mechanical properties like strength and durability. Additionally, it can lead to cracking, hot cracking, or corrosion.
Workshop Practice & Action Instructions
To avoid solid slag inclusion, thorough cleaning of the weld area is essential. Use high-quality fluxes and ensure correct application. For heavy contamination, it may help to grind or polish before welding. Regularly check the weld for defects and perform ongoing quality control.