EFFECT OF HYDROGEN-PEROXIDE ON ANODIC-DISSOLUTION AND CORROSION OF HOMOGENEOUS AG-ZN ALLOYS

The addition Of H2O2 to a sulfate solution had no effect on the anodic dissolution of silver and the alpha phase of the Ag-Zn system but accelerated the dissolution of zinc and its selective dissolution from beta, gamma, and epsilon phases. This indicated surface zinc on the latter phases. Cathodic depolarization greatly facilitated anodic dissolution of these phases with a resultant drop in corrosion resistance on transition from an alpha to a beta structure. The drop became more pronounced by oxo oxidants due to formation of adsorbed OH- that accelerated anodic zinc dissolution.