Summary
Iron‐gold alloys with compositions Fe70Au30 and Fe50Au50 were prepared by arc melting. The alloys were investigated by means of the high‐resolution scanning electron microscopy (SEM‐FEG) in the as‐cast state and upon annealing in two steps, i.e. at 250°C for 24 h and subsequently at 500°C for 48 h. The alloys were composed of two phases, i.e. a BCC phase rich in iron and a FCC phase rich in gold. The single‐phase regions have equivalent diameter of about 50 nm. SEM images show self‐similar structure for the spatial distribution of the above phases on scales ranging from about 1 mm till about 100 nm. The roughness of the images has been used to estimate a fractal dimension of the phase mixture. For larger scales of the as‐cast samples one finds fractal dimension of about 1.7 for Fe70Au30 composition, i.e. very close to the dimension of typical diffusion limited aggregation (DLA) fractals. For annealed samples, dimension 1.1 was found.