A localized corrosion process that attacks brass alloys containing more than 15 percent zinc. The zinc dissolves into the electrolyte, and the copper remains behind as a spongy, brittle mass that retains the original shape of the part but has no mechanical strength. It often leads to sudden catastrophic failure in valves and plumbing fixtures.
Heard on the job
The valve stem sheared off completely because dezincification turned the brass into a brittle sponge.
Insider tip
You can spot dezincification by a distinct color change: the affected brass turns from yellow to a dull, coppery red.
Also heard as
- red rot