Electron damage in Cu3Au

Abstract Ordered and disordered Cu3Au have been electron irradiated along over the temperature range 125–300 K in an H.V.E.M. The onset of structural changes has been monitored by using both the diffraction pattern to detect changes in the degree of order, and image information to observe clustered defects. It has been found that the threshold voltage for disordering an initially ordered sample is 325 kV, whereas only 305 kV is required to order an initially disordered sample. In contrast, it has been found that 355 kV is required to generate visible damage in an initially ordered sample, and 375 kV in an initially disordered sample. The significance of these results is discussed in terms of the displacement of copper atoms by the high-energy electrons.