Oxidation behavior of Cu-Ag alloy in-situ manufactured via laser powder bed fusion

The oxidation behavior of copper-silver (Cu-Ag) alloy with the structure of triply periodic minimal surfaces (TPMS) processed by laser powder bed fusion (LPBF) was investigated at 300 degrees C and 600 degrees C. The lightweight TPMSs increase surface area, boosting measurement sensitivity in oxidation studies. The presence of silver enhances oxidation resistance of Cu-Ag alloy compared to that of pure copper by slowing down the oxidation process and thinning the oxide layer. This suggests that silver in the alloy potentially suppresses the outward diffusion of copper from the substrate to the oxide layer. This effect is evident in the oxidation rate curves, where the introduction of silver changes the oxidation kinetics from a linear rate in Cu to a parabolic rate in Cu-2 wt.% Ag at 300 degrees C. Moreover, at 600 degrees C, silver induces a slower parabolic rate in Cu-2 wt.% Ag compared to Cu.