Simple procedure for phase identification using convergent beam electron diffraction patterns.

The use of the primitive cell volume and the zero order Laue zone (ZOLZ) pattern is proposed as a means to identify phases in a complex microstructure. A single convergent beam pattern, containing a higher order Laue zone ring, from a nanosized region is sufficient to calculate the primitive cell volume of the phase, while ZOLZ pattern is used to determine the zone axis of the crystal. A computer program is used to screen out possible phases on the basis of the value of measured cell volume. The indexing of the ZOLZ pattern follows in the program to find the zone axis of the identified phase. Combination of these two methods ensures accuracy and reliability of phase identification from a single CBED pattern. An example of the analysis is given from the rapidly solidified Al-Al3Ti system.