DEZINCIFICATION OF BRASSES

Mechanism of dezincification. DEZINCIFICATION is the term applied to the selective corrosion of zinc from copper zinc alloys, a form of deterioration that is easily recognisable by the copper‐coloured appearance of the corroded metal. It is often described as either ‘plug’ or ‘layer’ dezincification, but this division is largely arbitrary and merely indicates the appearance of the progress of attack and whether it is localised or general. Dezincification is not usually accompanied by any significant changes in the dimensions of the part undergoing attack, but the metal so attacked has no physical strength and has a structure of spongy copper. Consequently, components attacked in this way become weakened by reduction in effective cross section and eventually mechanical failure may occur.