High resolution observations of short-range ordering in disordered Au4Mn alloys
Observation of short range ordered (SRO) state in disordered binary alloys is the interesting topic in the point of order-disorder transition. The observation and analysis have been made with X-ray and neutron diffraction techniques which can give the SRO-parameters. These techniques, however, give only the information of an averaged structure. The ordering process is localized, so direct observations in atomic level by high resolution electron microscopy is needed for the detailed analysis.In the present study, disordered Au4Mn alloys were investigated with high resolution electron microscopy for the analysis of the origin of the characteristic SRO diffuse scattering (Fig. 1). The material was prepared by quenching and thinned by electrolytic polishing for microscopic observations. The specimen was observed along <120> direction by JEOL-200CX electron microscope (E=200keV).