Corrosion Behavior of Copper Alloys in Seawater with emphasis on UNC C95700

Copper based alloys are frequently used in marine water systems. They have indeed an attractive price and offer interesting mechanical characteristics associated to a relatively good resistance to corrosion in sea water. Nevertheless, they can suffer from certain forms of corrosion such as localized corrosion with sulphides pollution, crevice corrosion, or stress corrosion cracking in sea water more or less polluted with ammonia.The authorʹs purpose is to provide guidelines that will allow the engineer to make a reasonable estimate of the effect of the environment on the performance of copper alloys. The charts and summaries provide useful guideposts, but they can never replace the experience, specific data, or properly conducted evaluations so necessary to the successful use of materials. Temperature and pH values that are normal for the waters and usage under consideration are assumed.The principal constituents of water that affect the performance of copper alloys are dissolved oxygen, nutrients, bacteria, biofouling, organisms, sediment, trash, debris, and residual chlorine from the chlorination practice. Dissolved oxygen is usually reported in standard water analyses. Although the nature of sediments, bacteria, nutrients, biofouling organisms, debris, or chlorine present are often critical to performance, information on these important constituents is seldom included in water analyses and must be sought elsewhere.