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Potentiodynamic polarization analysis and electrochemical impedance spectroscopy, were used to determine the corrosion rate AISI 316L stainless steel (316L) in a NaOH-H 2 O working airconditioning mixture. The aqueous concentrations were 40% and 50% (w/w), temperature was set at 35°C and 90°C (similar to the conditions of the absorber and generator in an absorption airconditioning system). The results showed that the material exhibited a passivation region in all cases, and the corrosion mechanism was dominated by charge transfer. Additionally, at 35°C and 90°C the corrosion process was mainly influenced by the concentration and temperature of the solution. The results were attributed to the steel chemical composition, the chemical stability of the corrosion products, the structural state of the passive film, and the ability to prevent the diffusion of metal ions. According to the results, the NaOH-H 2 O mixture possesses electrochemical characteristics that permit its application as a working fluid for air-conditioning absorption processes.

The corrosion behavior of the Fe40Al60nanostructured intermetallic composition was studied using electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LPR) techniques with an innovative electrochemical cell arrangement. The Fe40Al60(% at) intermetallic composition was obtained by mechanical alloying using elemental powders of Fe (99.99%) and Al (99.99%). All electrochemical testing was carried out in Fe40Al60particles that were in water with different pH values. Temperature and test time were also varied. The experimental data was analyzed as an indicator of the monitoring of the particle corrosion current densityicorr. Different oxide types that were formed at surface particle were found. These oxides promote two types of surface corrosion mechanisms: (i) diffusion and (ii) charge transfer mechanisms, which are a function oficorrbehavior of the solution, pH, temperature, and test time. The intermetallic was characterized before and after each test by transmission electron microscopy. Furthermore, the results show that at the surface particles uniform corrosion takes place. These results confirm that it is possible to sense the nanoparticle corrosion behavior by EIS and LPR conventional electrochemical techniques.