Oxide scale on cut edges
The oxide layer on cut edges forms during thermal cutting with oxygen-rich gases. It must be removed before coating processes.
Physical-Chemical Mechanism of Action
The oxide layer forms by reaction of metal atoms with oxygen from the process gases. This results in a stable layer at the cut edge, protecting the metal and making it chemically inert.
Metallurgical Relevance & Risks in Welding
The oxide layer can cause problems in coating processes because it reduces the contact area between the metal and the coating material. This leads to poor coating results and increases the risk of corrosion.
Workshop Practice & Instructions
Before coating processes, the oxide layer must be removed, e.g., by chemical cleaning or mechanical polishing. This can be done with a fine polishing compound and a polishing wheel. Make sure the cut edges are completely clean before continuing.