where does corrosion occur in a galvanic cell
Galvanic corrosion Dissimilar metals and alloys have different electrode potentials, and when two or more come into contact in an electrolyte, one metal acts as anode and the other as cathode. If the electrolyte contains only metal ions that are not easily reduced (such as Na+, Ca2+, K+, Mg2+, or Zn2+), the cathode reaction is reduction of dissolved H+ to H2 or O2 to OHâˆ’.[1][2][3][4] The electropotential difference between the reactions at the two electrodes is the driving force for an accelerated attack on the anode metal, which dissolves into the electrolyte. This leads to the metal at the anode corroding more quickly than it otherwise would and corrosion at the cathode being inhibited. The presence of an electrolyte and an electrical conducting path between the metals is essential for galvanic corrosion to occur. The electrolyte provides a means for ion migration whereby ions move to prevent charge build-up that would otherwise stop the reaction.