Atmospheric Corrosion of Copper Alloys Exposed for 15 to 20 Years

Copper alloys were exposed for 15 to 20 years at two marine, one industrial, and one rural location. Based on average corrosion rates for 13 alloys, the industrial corrosion rate was 1.4 µm/year whereas the rate for the other sites was approximately 0.7 µm/year. As expected, alloying agents affected the corrosion rates by a factor of 2 to 3.

General attack was the predominant form of corrosion. Dezincification was positively identified in C260 alloy and intergranular attack was noted in C642. Pitting was not a factor for any alloy.