Character of the dissolution and partial electrode processes at the alternating-current infralow-frequency polarization of brasses in chloride media.: II.: Cu44Zn β-brass

The dissolution of beta-brasses in a chloride medium at a pulse anodic polarization proceeds at first (up to similar to 1 min) nearly uniformly, but when the charge of anodic pulse is carried out partly on the ionization of zinc and partly on the ionization of copper, it becomes selective. In this case the most part of the copper component does not oxidize, but rearranges to form the individual phase, which causes a substantial destruction of the brass electrode. When the cathodic alternating-current component is also switched on and hydrogen evolution begins, pH of the layer near electrode increases preventing the formation of soluble oxidation products in the subsequent anodic half-period. Thus, on a beta-brass electrode, the partial cathodic processes affect the anodic oxidation of copper and zinc.