Brazing Crevice Corrosion
Brazing crevice corrosion occurs in narrow gaps that are not fully penetrated or sealed by the filler metal. Electrochemical potential differences drive the corrosion process.
Physical-chemical mechanism
Brazing crevice corrosion occurs when an electrolyte mixture is present in narrow gaps (e.g., from brazing or weld seams) and is not completely penetrated by the filler metal. The electrochemical potential differences between the metal phases cause ions to be released and corrosion to build up.
Metallurgical relevance & welding risks
This corrosion can lead to cracks and wear of the parts. It is particularly dangerous in complex parts with many gaps or with poor sealing. Insufficient brazing or a faulty weld seam can promote the development of this corrosion.
Workshop practice & instructions
To avoid brazing crevice corrosion, gaps must be completely penetrated by the filler metal and carefully sealed. For weld seams, ensure high temperature and sufficient time to properly fuse the metal. If necessary, use special corrosion inhibitors or sealing compounds.