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Point Defect Mechanisms in Deformation and Phase Transformation of Titanium Aluminide Alloys

Published online by Cambridge University Press:  11 February 2011

Fritz Appel
Affiliation:
Institute for Materials Research, GKSS-Research Centre Geesthacht, Max-Planck-Str. 1 D-21502 Geesthacht, Germany
Jonathan D.H. Paul
Affiliation:
Institute for Materials Research, GKSS-Research Centre Geesthacht, Max-Planck-Str. 1 D-21502 Geesthacht, Germany
Ulrich Fröbel
Affiliation:
Institute for Materials Research, GKSS-Research Centre Geesthacht, Max-Planck-Str. 1 D-21502 Geesthacht, Germany
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Abstract

Point defects in intermetallic compounds are subjected to significant constraints due to the directional bonding, long-range order and off-stoichiometric deviation of the materials. This leads to a variety of defects with distinct differences in morphology, concentration and mobility. In the present study the implications of these defect characteristics on the mechanical properties of two-phase titanium aluminide alloys will be investigated. The major areas of the study are: (i) deformation induced point defects that contribute to work hardening; (ii) dislocation locking due to the formation of defect atmospheres; (iii) transport processes involved in phase transformation and recrystallization occurring during long-term creep. The applied methods include mechanical testing, static strain aging and structural characterisation by high resolution electron microscopy.

Type
Research Article
Copyright
Copyright © Materials Research Society 2003

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