The phenomenon of dealloying, in general, and dezincification of brasses, in particular, has been studied for quite sometime.1,2 To explain dezincification, two theories have been proposed:3,4 (1) selective dissolution of Zn atoms alone takes place from the parent brass in the presence of an electrolyte leaving a porous copper residue, or (2) both Cu and Zn atoms dissolve simultaneously in the electrolyte with which they are in contact with subsequent redeposition of Cu alone. In order to assess which of the above two mechanisms is operative, several studies have been carried out simulating the conditions for dezincification.
In the present work, studies have been made on a cartridge brass sample which had undergone dezincification during manufacture. The sample, after mounting and careful polishing, was observed under an optical microscope. Figure 1 shows a photomicrograph showing a typical dezincified area in which the interface between the parent brass and...
