Gardner Haynes

Cyclic Polarization Measurements—Experimental Procedure and Evaluation of Test Data

ASTM Subcommittee G01.11 on Electrochemical Measurements in Corrosion Testing has conducted round-robin testing on the reproducibility of cyclic potentiodynamic polarization measurements for determining susceptibility to localized corrosion. This work was used in the development of a practice that provides a standard experimental procedure for conducting these tests. This paper presents the experimental procedure and results of the round-robin tests with statistical analysis of the data. The reproducibility of the measurements and sources of error are discussed.

Galvanic corrosion of ferritic stainless steels in seawater

Galvanic behavior of stainless steels in seawater is difficult to predict because of their susceptibility to localized corrosion. This susceptibility can be either enhanced or eliminated depending on the particular galvanic couple. This paper deals with seawater corrosion of several ferritic stainless steels in galvanic couples. Methods of predicting their behavior are described based on electrochemical polarization measurements, various laboratory tests, and actual immersion in seawater. Results of electrochemical and laboratory tests are compared with those obtained in seawater. The validity of each of the test procedures is discussed with regard to alloy development and designing materials systems.

Corrosion Evaluation of Steel Clad Copper Concentric Neutrals

Corrosion of bare and tin alloy coated copper concentric neutral strands in underground distribution cable has received much attention in recent years. Although disagreement still exists on the extent of the problem and the mechanisms that cause it, a number of mitigative techniques are being evaluated.

Atmospheric Corrosion of Laminar Composites Consisting of Copper on Stainless Steel

Atmospheric corrosion of laminar composites consisting of copper on stainless steels has been studied through direct exposure of copper-clad ferritic and austenitic stainless steels to provide information on galvanic effects at cut edges and pores in the copper cladding. Qualitative and quantitative results after exposure for 7.5 years are presented and environmental effects are considered. Application of electrochemical techniques for predicting galvanically induced localized corrosion are discussed and related to environmental conditions and alloy composition. Mechanisms for galvanic pitting and crevice corrosion are correlated with service performance of the copper-stainless steel couples.