Linear slag inclusions
Linear slag inclusions are string-like entrapped molten flux or slag in the weld metal. They weaken the joint and can lead to cracking.
Physical and chemical mechanism of action
Linear slag inclusions occur when molten flux or slag gets trapped in the weld metal during welding. This can be caused by insufficient cleaning of the workpiece or the weld puddle.
Metallurgical relevance & risks in welding
These inclusions reduce the mechanical strength and toughness of the joint. They can lead to cracks, hot cracks, or stress concentrations, which affect the service life and reliability of the weld.
Workshop practice & action instructions
To avoid linear slag inclusions, thorough cleaning of the workpiece is essential. Use high-quality flux and pay attention to proper application. If you suspect them, carry out a microscopic examination to ensure no inclusions are present.