The Change in Colour of a Silver-Gold Alloy on Plastic Deformation

Abstract

The colour change when deformed samples of the alloy AgAu are annealed has been confInned and an attempt has been made to measure it in terms of the movement of the spectral absorption edge. It is found that on annealing the absorption edge of a heavily deformed sample moves about 5�4 mp, toward shorter wavelengths. No such effect was observed in the pure metals, silver and gold. It is suggested that the effect may be connected with the presence of short-range order and/or with a migration of silver atoms to the surface in the annealing process.