Extended solubility in non-equilibrium Pb/Fe system

Nanostructured Pb/Fe alloys have been produced by means of mechanosynthesis and co-deposition methods in powder and film forms, respectively, in both sides of the composition range. Low temperature Mِssbauer results obtained from the films have indicated the presence of interstitial Fe in fcc-Pb lattice, with maximum Fe solubility of 3 at.%. This Fe configuration has an atomic diffusion effect with increasing temperature, resulting in formation of small Fe clusters. On the other hand, milling Fe and Pb powders mixture up to 700 h only produced iron-rich Pb/Fe phases with high degree of chemical disorder established due to different atomic radii of Pb and Fe, as shown by a broad Mِssbauer subspectra. The milling procedure extended the Pb solubility limit in Fe matrix to 6 at.%. Therefore, our results of films and milled powders indicated that one has extended the known solubility limit for this system.