Hostname: page-component-cd9895bd7-7cvxr Total loading time: 0 Render date: 2024-12-25T02:35:45.984Z Has data issue: false hasContentIssue false
  • English
  • Français

A Study of the Unusual Line Structure in Powder Patterns of Pyrolytically Deposited Boron Compounds and Other Materials

Published online by Cambridge University Press:  06 March 2019

Robert L. Prickett ,
R. L. Hough  and
Duane Earley
Robert L. Prickett
Affiliation:
Air Force Materials Laboratory Wright-Patterson AFB, Ohio
R. L. Hough
Affiliation:
Hough Laboratories Springfield, Ohio
Duane Earley
Affiliation:
University of Dayton Dayton, Ohio
Get access

Abstract

A prolonged study has been roade of the unusual X-ray powder patterns generated by certain pyrolytically formed boron compounds, consisting of two to four moderately broad diffraction lines in the 1-4 Å range. These broad lines are unexpectedly made to disappear by a singie sharp blow with a hammer on the specimen in a Plattner diamond mortar, the disappearance being accompanied by the spontaneous generation of the standard diffraction lines expected for normally crystalline materials. The same diffraction pattern changes also may be brought about by regular grinding methods, fracture, or thermal annealing. Transmission electron diffraction yields results identical with those obtained by X-ray. Orientation studies demonstrate that the phenomenon is not orientation dependent. Controlled fracture has been applied in an attempt to develop a hypothesis. It appears from the constancy of the width and position of the diffraction lines among samples that the phenomenon being studied has a definite potential energy, well located somewhere between amorphous and crystalline states. Demonstration of this phenomenon of line broadening has been obtained with boron, boron carbide, and in part with silicon, carbide. These materials have been formed by various methods: pyrolytic decomposition of carborane, low pressure electrical discharge in diborane, chemical reaction between boron halide and hydrogen.

Type
Research Article
Information
Advances in X-Ray Analysis , Volume 10: Fifteenth Annual Conference on Applications of X-ray Analysis, August 10-12, 1966 , 1966 , pp. 221 - 233
Copyright
Copyright © International Centre for Diffraction Data 1966

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. Prickett, R. L. and Hough, R. L., “Generation of Two Dimensional Silicon Carbide Lattice,” in Advances in X-Ray Analysis, Vol. 9, Plenum Press, New York, 1966, p. 144.Google Scholar
2.Lockheed Missile and Space Company, “Research to Study the Structure of Non-Crystalline Boron,” Contract AF33(615)-3140, third quarter progress report, April 1966, p. 13, 37.Google Scholar
3.Lockheed Missile and Space Company, “Research to Study the Structure of Non-Crystalline Boron,” Contract AF33(615)-3140, second quarter progress report, January 1966, p. 13,Google Scholar
4. Lipsitt, H. A., “A Study of Boron Filaments,” Metallurgy and Ceramics Research Laboratory, Wright-Patterson AFB, 1965.Google Scholar
5. Otte, H. M. and Lipsitt, H. A., “On the Interpretation of Electron Diffraction Patterns from ‘Amorphous’ Boron,” Phy. Stat. Solidi 13: 439, 1966.Google Scholar
6.General Electric Company, “Research in Improved High Modulus, High Strength Filament and Composites Thereof,” Tech. Rep. AFML-TR-65-319, September 1965, pp. 129 and 159.Google Scholar
7. Guinier, A., X-Ray Cryslallcgraphic Technology, Hilger and Watts, Ltd., London, 1952, p. 107.Google Scholar
8. Neuburger, M. C., “Gitterkonstartten fur das Jahr, 1936,” Z. Kristallograpkie-Mineralogie 93: 1, 1936.Google Scholar
9. Welis, A. F., Structural Inorganic Chemistry, Oxford, London, 1962, pp. 55 and 849.Google Scholar
10. Taylor, A., X-Ray Metallography, John Wiley and Sons, Inc., New York, 1961, p. 786.Google Scholar
11.General Technologies Corporation, Air Force Materials Laboratory, Tech. Rep. 65-265.Google Scholar
12. Mazdiyasni, K. S., Lynch, C. T., and Smith, J. S., “Meta-Stable Transitions of Zirconium Oxide Obtained from Decomposition of Alkoxidcs,” J. Am. Ceram. Soc. 49: 286, 1966.Google Scholar
13. Newsome, J. W., Heiser, H. W., Russell, A. S., and Stumpf, H. C., Alimina Properties, Aluminum Company of America, Pittsburgh, 1960, p. 70.Google Scholar
14. Frankenburg, W. G., Komarewsky, V. I., and Rideal, E. K. (eds.), Advances in Catalysis, Vol. 2, Academic Press, New York, 1950, p. 100.Google Scholar