Hostname: page-component-848d4c4894-v5vhk Total loading time: 0 Render date: 2024-06-19T08:51:17.991Z Has data issue: false hasContentIssue false
  • English
  • Français

Orientation of Back Reflection Laue Photographs: A Semi-Automated Approach

Published online by Cambridge University Press:  06 March 2019

R. P. Goehner
R. P. Goehner*
Affiliation:
Corporate Research and Development General Electric Company Schenectady, New York 12301
Get access

Abstract

Computer simulation of back reflection Laue patterns now provides the means to plot Laue patterns for any crystal system in any orientation. This capability makes it possible to determine, rapidly and accurately, the orientation of single crystals and large grains in polycrystalline materials even in cases where little or no symmetry is displayed in the Laue photograph. A set of standard Laue patterns is first simulated to cover the stereographic triangle of the crystal being studied. The Laue photograph obtained from the crystal, or grain, is compared with the set of simulated Laue patterns. The pattern most similar to the photograph is used to determine the (HKL) values of three Laue spots. The (HKL) values of these spots and half their angular separations from the x-ray beam, along with the lattice constants, are used by a computer program to calculate the (HKL) value of the crystallographic plane perpendicular to the x-ray beam. A simulated Laue pattern can now be obtained in exactly the same orientation and it can be drawn directly to the scale of the Laue photograph. Thus the validity of the orientation can be easily verified by direct comparison. The (HKL) value of the crystallographic plane perpendicular to the x-ray beam can also be used to plot a stereographic projection of the crystal poles. Therefore, the complete orientation of the crystal can be determined.

Type
X-Ray Diffraction Applications
Information
Advances in X-Ray Analysis , Volume 19: Twenty-Fourth Annual Conference on Applications of X-ray Analysis, August 6-8, 1975 , 1975 , pp. 725 - 734
Copyright
Copyright © International Centre for Diffraction Data 1975

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Wood, E. A., “Crystal Orientation Manual”, Columbia University Press (1963).Google Scholar
2. Preuss, E., Krahl-Urban, B. and Butz, R., “Laue Atlas”, John Wiley and Sons (1974).Google Scholar
3. Preuss, E., “Rechenverfahren und ComputerprogrammezurAuswertung von Laue - und von Kassel-Dragrammen”, Beuchte der Kernforshungsanlage Julich, No. 821 (1972).Google Scholar
4. Goehner, R. P., “Simulation of Back Reflection Laue Patterns”, Report No. 75CRDO50, General Electric Company, Corporate Research and Development, Schenectady, New York (1975).Google Scholar
5. Dunn, C. G. and Martin, W. W., “The Rapid Determination of Orientation of Cubic Crystals”, Trans. AIME 185, 417–427 (1949).Google Scholar
6. Johari, O. and Thomas, G., “The Stereographic Projection and Its Applications”, R. F. Bunshah, Editor, Techniques of Metals Research, Vol. IIA, Interscience (1969).Google Scholar
7. Ku, F. Y. and Richman, M. H., “Computation of Standard Projections for a Triclinic System of Arbitrary Orientation”, Metallography 5, 501–513 (1972).Google Scholar
8. Ploc, R. O. and Barnett, P. C., “Computer-generated Stereographic Projections”, J. Appl. Cryst. 5, 135–136 (1972).Google Scholar
9. Goehner, R. P., “Automatic Plotting of Stereographic Projections”, Report No. 73CRD212, General Electric Company, Corporate Research and Development, Schenectady, New York (1973).Google Scholar
10. Goehner, R. P., Unpublished Computer Program (1974).Google Scholar
11. Bartram, S. F. and Goehner, R. P., Unpublished Work (1974).Google Scholar