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This series of articles describes a method that performs (semi)quantitative phase analysis for nanocrystalline transmission electron microscope samples from selected area electron diffraction (SAED) patterns. Volume fractions of phases and their textures are obtained separately in the method. First, the two-dimensional SAED pattern is converted into an X-ray diffraction-like one-dimensional distribution. Volume fractions of the nanocrystalline components are determined by fitting the spectral components, calculated for the previously identified phases with a priori known structures. Blackman correction is also applied to take into account dynamic effects for medium grain sizes. Peak shapes and experimental parameters (camera length, etc.) are refined during the fitting iterations. Parameter space is explored with the help of the Downhill-SIMPLEX algorithm. Part I presented the principles, while Part II now elaborates current implementation, and Part III will demonstrate its usage by examples. The method is implemented in a computer program that runs under the Windows operating system on IBM PC compatible machines.

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Ultrafine-grained titanium was processed by severe plastic deformation (SPD). The SPD was carried out by equal channel angular pressing (ECAP) at high temperature. The ECAPprocessed sample was further deformed by conventional techniques such as radial forging and drawing. The microstructure was characterized quantitatively by X-ray diffraction line profile analysis and transmission electron microscopy after each step of deformation. The effect of procesing routes on the mechanical behavior was also studied. It was found that the conventional deformation processes after ECAP result in further increment in dislocation density and strength at the expense of ductility.

A free computer program was introduced recently to process electron diffraction ring patterns. The program (called ProcessDiffraction) produces XDR-like output from the digitized version of the measured diffraction patterns. The enhanced functionality of V1.2 is summarized in the present paper.1.The program starts with a hint-window giving suggestions what can be done next. Hints change permanently as processing progresses. The hint-window can be switched off optionally. It is a complement to the Windows-style Help-system.2.The center of the rings is found by manually shifting the measured pattern until it overlaps with a generated reference circle. The computer can further refine the position of the center.3.Elliptical distortion of the measured pattern (NOT of the display, which is irrelevant) is corrected by adjusting the eccentricity and axis direction of the reference ellipse (distorted from the reference circle) until visually coincide with the measured ring.

A peak‐to‐background (P/B) method was implemented for standardless analysis of bulk samples. Components of the model were selected from the literature on the basis of comparison with the present experimental results. Pouchou and Pichoir's characteristic x‐ray intensity calculations combined with Small et al. bremsstrahlung model proved to be the most successful in this respect. An empirical modification seems to be necessary to improve the agreement between calculated and measured P/Bs for the Lα lines of single‐element samples. For modelling the dependence of the measured P/B on the particle size, small particles are approximated as thin layers. Preliminary experimental results illustrate that even such a rough approximation works.

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