Oxidic interlayer inclusions
Oxide interrun inclusions are trapped metal oxides between weld beads, caused by insufficient cleaning. They cause defects and reduce weld strength.
Physico-chemical mechanism of action
Oxide interlayer inclusions occur when the metal is not thoroughly cleaned during the welding process. This leads to an accumulation of oxide on the surface and in the interlayers between weld passes.
Metallurgical relevance & risks in welding
These inclusions can cause damage to the microstructure, as they reduce the mechanical strength and corrosion resistance of the weld. They can also serve as sources for hot cracks, especially when the metal is under stress.
Workshop practice & instructions
To avoid oxide interlayer inclusions, it is crucial to thoroughly clean the weld surfaces before welding. This can be achieved by removing dirt, rust, and other contaminants. A correct cleaning method and sufficient time for surface drying are essential. For materials that are difficult to clean, chemical cleaning or the use of protective agents can be helpful.