THE EFFECT OF THE SHAPE FUNCTION ON SMALL-ANGLE SCATTERING ANALYSIS BY THE MAXIMUM-ENTROPY METHOD

Analysis of small-angle scattering data to obtain a particle-size dist ribution is dependent upon the shape function used to model the scatte ring. From a maximum-entropy analysis of small-angle scattering data, the effect of shape-function selection on the obtained size distributi on is demonstrated using three different shape functions to describe t he same scattering data from each of two alloys. The alloys have been revealed by electron microscopy to contain a distribution of randomly oriented and mainly noninteracting irregular ellipsoidal precipitates. A comparison is made between the different forms of the shape functio n. The effect of an incident-wavelength distribution is also shown. Th e importance of testing appropriate shape functions and validating the se against other microstructural studies is discussed.