The structure of bcc-Fe80Cu20 solid solution produced by mechanical alloying of the elemental bcc-Fe and fcc-Cu powders has been studied using X-ray diffraction and the extended X-ray absorption fine structure (EXAFS) techniques. The disappearance of elemental Fe and Cu X-ray diffraction (XRD) peaks and the presence of bcc structural XRD peaks illustrate the formation of a nanocrystalline single-phase bcc-Fe80Cu20 solid solution. From the EXAFS result, the clear observation of Cu atoms taking on bcc coordination in the solid solution and Fe atoms remaining bcc structure further verifies the reality of atomic alloying between Fe and Cu atoms and the lattice change of Cu from fcc to bcc. However, the supersaturated bcc solid solution is not chemically uniform, i.e., some regions are rich in Fe atoms and other regions rich in Cu atoms.
Y.Z. Yang, X.J. Bai, T.C. Kuang, G.M. Wang and S.Q. WeiFaculty of Materials and Energy, Guangdong University of Technology, Guangzhou 510090, ChinaCenter of Structure Analysis, University of Science and Technology of China, Hefei 230026, China Manuscript
