Application of Scanning Electrochemical Microscopy to Determine Electrochemical Activity of Intermetallics for an Al-Si-Mg Alloy in Chloride Solution

摘要

In this work a scanning electrochemical microscopy (SECM) study of electrochemical activity for intermetallics in the Al-1.78%Si-13.4%Mg alloy was carried out. For the experiments, a 0.1M NaCl solution with hidroxymethlyferrocene as a mediator and a Pt scanning probe 25 um in diameter were used. SECM images obtained while the sample was held at open circuit conditions were compared to optical photomicrographs in the same area. The electrochemical activity of the intermetallics Mg_2Si and Al_3Fe is discussed.