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Site Occupation of Excess Al Atoms in Off-Stoichiometric γ-Tial: Measurement of Debye-Waller Factors

Published online by Cambridge University Press:  22 February 2011

S. Swaminathan
Affiliation:
Dept. of Mat. Sci. and Engineering, The Ohio State University, Columbus, OH
I. P. Jones
Affiliation:
School of Metallurgy and Materials, University of Birmingham, Birmingham, UK
D. M. Maher
Affiliation:
Dept. of Mat. Sci. and Engineering, North Carolina State University, Raleigh, NC
H. L. Fraser
Affiliation:
Dept. of Mat. Sci. and Engineering, The Ohio State University, Columbus, OH
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Abstract

In recent years, the determination of x-ray structure factors and hence the electron charge density distribution in TiAl has received considerable attention. Experimental assessment of electron charge densities requires accurate values of the Debye-Waller (D-W) factors. This work attempts to determine the Debye-Waller factors from measurements of an Al rich off-stoichiometric single crystal of TiAl using the four circle x-ray diffraction method. The results suggest an ordered substitution of the excess Al atoms on the Ti-sublattice. This result is consistent with previous site occupancy studies.

Type
Research Article
Copyright
Copyright © Materials Research Society 1995

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