J. Phys. IV France 12 (2002) Pr6-455
Correlation between ball milling conditions and planar effects on Cu-nanostructured powdersF. Bernard1, E. Gaffet2, Y. Champion3, N. Budarina4 and A. Ustinov4
1 LRRS, UMR 5613 du CNRS, Université de Bourgogne, BP. 47870, 21078 Dijon, France
2 Nanomaterials, UMR 5060 du CNRS, UTBM, 90010 Belfort, France
3 CECM-CNRS, 15 rue Georges Urbain, 94407 Vitry-sur-Seine, France
4 G.V. Kurdumov Institute for Metal Physics, 36 Vernadsky Str., Kiev 03142, Ukraine
It is most often proposed that the process of ball milling introduces a variety of defects (vacancies, dislocations, grain boundaries, stacking faults,...) which raise the free energy of the system making it possible to produce metastable phases. But there are very few investigations that deal with the characterization and quantification of the defects produced in milled powders. XRD is really a valuable technique for a characterization in terms of size and morphology of crystallites and imperfections. In this paper, a new line profile analysis method is proposed in order to take into account the dependence of the crystallite size, of the residual strains as well as of the planar defects, on the line profile broadening that may be observed on ball-milled materials. Such a method will allow to understand the influence of ball-milling parameters and for controlling the synthesis of nanostructured materials. The results concern the XRD pattern simulation, in a kinematic approach, of FCC. nanocopper produced by ball milling and containing a high concentration of planar defects. Simulations are compared to the experimental data. Analysis and interpretations of the results could rely on local observations of defects using high-resolution electron microscopy.
© EDP Sciences 2002