Corrosion properties, chemical composition, and surface morphology of non-ferrous metals after tests at different temperature and humidity conditions

In order to predict the shelf life of non-ferrous metals, laboratory studies into the kinetics of corrosion processes of metals under various temperature and humidity conditions were performed. The results of 12-month corrosion tests of the following non-ferrous metals are presented: aluminum, cobalt, copper, nickel, tin, lead, and zinc at various relative humidity and air temperature conditions. All the metals studied were found to be corrosion-resistant under atmospheric conditions at a relative humidity of no more than 80% and an air temperature of no more than 30 °C. An increase in air humidity from 70 to 95% and air temperature from 20 to 50 °C leads to an increase in corrosion-induced losses of metals, primarily for zinc, cobalt, and lead. During the tests, changes in the appearance of the sample surface were recorded. The chemical and phase composition of oxide films on the metal surface, as well as their morphology, were studied after different test periods. The results will be used in future works in developing methods for predicting the shelf life of non-ferrous metals.