Accelerated testing of copper corrosion

An innovative, short-term corrosion test has been developed that can predict long-term copper corrosion behavior. When used in a six-day study of uniform copper corrosion in five waters, the test predicted corrosion rates that were in good qualitative and quantitative agreement with known long-term (210-day) results. A second phase of the study examined the poorly understood phenomenon of soft-water pitting. Initial work successfully reproduced softwater copper pitting in the laboratory using a synthetic water, facilitating future studies of pit initiation and potential remedies. Relative pitting tendencies were predicted using the short-term test, as was the long-term release of the by-products of copper corrosion. Pitting severity increased with increasing pH and duration of stagnation and decreased in the presence of natural organic matter or chlorine residuals.