CORROSION FATIGUE OF COPPER AND ALPHA-BRASS.

The electrolytes employed were pre-oxygenated solutions of ammoniacal copper sulfate for both copper and alpha-brass specimens, and pre-oxygenated solutions of sodium chloride and copper sulfate for copper specimens. All electrolytes reduced the ftigue life relative to a reference environment of preoxygenated double distilled water, and electron diffraction studies of undisturbed fatigue fracture surfaces revealed the presence of cuprous oxide. accordingly, the mechanism of corrosion fatigue was believed to be generally consistent with a model based on enhanced localized electrochemical dissolution at the tip of the fatigue crack due to the formatio and rupture of cuprous oxide films in a manner similar to that proposed for tarnish rupture theories of stress-corrosion cracking.