Application of higher order laue zone patterns to lattice parameter determination in cu-based alloys

Higher order Laue zone (HOLZ) patterns in some copper-based alloys were examined in order to investigate the validity of a kinematical treatment to determine the accurate value for lattice parameters. The calculation based on a dynamical electron diffraction theory showed that the location of the HOLZ lines depends upon the magnitude of crystal potential, and that correspondingly the value for the lattice parameter given by the kinematical treatment deviates from the true value. However, the kinematical treatment is still valid if a proper crystal specimen is used as a standard for correction against the deviation. The kinematical treatment was practically applied to Cu-AI, Cu-Mn, Cu-NI, Cu-Zn, and Cu-Ga alloys, and after the correction using pure Cu as a standard, a fairly good agreement was obtained between the lattice parameters determined by the kinematical treatment and those predicted from the chemical composition of the alloys.