Pitting Behavior of Aluminum Alloys in High Velocity Sea water,

摘要

A quantitative electrochemical technique would be useful for evaluation of the pitting behavior of aluminum alloys in high velocity sea water. However,controversy exists about the relevance of using anodic polarization measurements for determination of pitting susceptibility of aluminum alloys even in quiescent sea water or in laboratory chloride solutions. Pryor (1) and Galvele (2) have proposed that valid critical pitting potentials can be determined on aluminum alloys exposed to deaerated sodium chloride solutions,but that critical pitting potentials in aerated sodium chloride solutions are meaningless. Wood,et. al., (3) have proposed that the mechanism and morphology of pitting are different for pits initiated at potentials more noble than the critical pitting potential compared to pits initiated at more active potentials. Macropits and micropits are observed at the more active potentials while only micropits are observed at potentials more noble than the critical potential. (Author)