DIFFRACTION LINE BROADENING - NUISANCE OR LATTICE-IMPERFECTIONS FINGERPRINTS

Diffraction lines are broadened for two reasons: instrumental configur ation and physical origins. The latter yields information on materials microstructure. The complete process of line-broadening analysis is d iscussed, beginning with experimental procedures and a correction for instrumental broadening. In the analysis of the physically broadened l ine profile, the main emphasis is given to the widely used methods of separation of size and strain broadening: the Warren-Averbach approxim ation and integral-breadth methods. The integral-breadth methods are c ollated and their reliability discussed. Close attention is given to a n assumed Voigt-function profile shape for both size-broadened and str ain-broadened profiles because it is shown that a Voigt function fits satisfactorily the physically broadened line profiles of W and MgO obt ained by the Stokes-deconvolution method. The subsequent analyses of b roadening are performed by using the Warren-Averbach and ''double-Voig t'' approaches and results are compared.