Influence of thermo-mechanical treatment on the electrochemical behavior of cast and sintered dilute Cu–Au alloy

This paper presents the results on the influence of thermo-mechanical treatment on the electrochemical behavior of cast and sintered Cu-4at.%Au alloy. The results were obtained by using both open circuit potential measurement and cyclic voltammetry in a NaOH solution. The microstructural and the mechanical properties were concurrently investigated. The thermo-mechanical treatment included pre-final rolling, solution annealing followed by quenching, final rolling, anneal hardening, and recrystallization annealing. Depending on the thermo-mechanical treatment, various microstructures were obtained, as a result different mechanical and electrochemical properties were attained. The anneal-hardened samples had the highest mechanical properties, as well as the most positive open circuit potential values. According to the cyclic voltammograms, the finally rolled samples had the best corrosion resistance compared with the samples taken after other steps of the thermo-mechanical treatment. The additional annealing contributed to a decrease in the corrosion resistance. After every stage of applied thermo-mechanical treatment the cast alloys exhibited a lower corrosion resistance than the sintered ones, since the corrosion rate increased with an increase in average grain size. •Significant changes in properties occurred in cast and sintered Cu-4at.%Au alloy during the thermo-mechanical treatment.•Anneal-hardened samples had the highest mechanical properties as well as the most positive open circuit potential values.•The cast alloys exhibited a lower corrosion resistance than the sintered ones.