Corrosion resistance of aluminum-lithium alloys under various climatic conditions

The corrosion resistance (stress corrosion cracking, exfoliation, intergranular corrosion) of a wide group of aluminum-lithium alloys has been studied under atmospheric conditions with various corrosion environments. Corrosion behavior of experimental and commercial batches of aluminum-lithium alloys has been established as a function of the chemical composition of the alloys and ratio of Cu/Mg, Li/Cu + Mg. Under atmospheric conditions, the best corrosion properties are those of an alloy with a Cu/Mg ratio of 0.5 and a ration of Li/Cu + Mg of 0.96. It has been proved that a decrease in Li/Cu + Mg to 0.56–0.76 leads to impairment of corrosion properties. Accelerated corrosion tests result in the same conclusions.