A comparison between the Warren-Averbach method and alternate methods for X-ray diffraction microstructure analysis of polycrystalline specimens

The fundamental parameters approach, used to simulate the instrument contribution to an XRD profile, eliminates the need to prepare experimentally a reference sample of the studied crystalline material when using the Warren-Averbach method to investigate microstructural parameters. The Warren-Averbach method is compared to the Balzar and Enzo methods of size-strain analysis. The analysis was carried out using boehmite powder having two different nominal average crystallite sizes, 8 nm and 20 nm. A 50-50% mixture of these materials was used as a third sample. The proposed simulation procedure provides good results and is much faster to implement than the usual procedure that includes the preparation of a reference. For larger crystallite sizes, the results calculated from the Warren-Averbach method for the volume-weighted average crystallite size differs significantly from those obtained from the Balzar and Enzo methods. The limitations of the Balzar and Enzo methods are discussed. 32 refs.