Effect of sintering time on corrosion behavior of an Ag/Al/Nb/Ti/Zn alloy system

Abstract High-entropy alloys are interesting for both aerospace and biomedical applications. Additionally, their application into a corrosive environment is also demanded. Investigations concerning to the effects in the sintering time on the microstructural features of an AgAlNbTiZn alloy system and correlating with corrosion behavior are scarce. This investigation is focused on the evaluation of the corrosion behavior of an AgAlNbTiZn alloy system in a 0.5 M NaCl solution at 25 °C. Experimental and simulated EIS parameters and potentiodynamic polarization curves are discussed. It is found that both the dispersed-Nb particles and the TiAl intermetallics constitute the microstructural arrays affecting significantly the cathode-to-anode area ratio. Consequently, the corrosion behavior is also substantially modified. It is also found that the sintered sample during 12 h reveals some colonies of the TiAl intermetallic interfacing with the Nb powder particles. These are lower (∼3x) than the sintered sample for 24 h. This evidences that the microstructural array has an important role on the corrosion current density and polarization resistance of the samples examined.