Application of mylius thermometric technique to the study of galvanic corrosion

ABSTRACT

The Mylius thermometric technique, originally developed to examine general corrosion, is extended to cover galvanic corrosion. Pure zinc coupons dissolve in HCl solutions with the evolution of heat. The temperature-time curves exhibit a maximum whose value depends on acid concentration. Coupling the zinc coupons to copper causes increase in temperature maximum and in reaction number [R.N.]. The increase in R.N. varies linearly with the area of the copper cathode. A corresponding change in the rate of zinc dissolution is also registered. Both effects are explained on the basis of the catchment area principle