Title of article :
Comparison of glide mechanisms in hcp Ti and Ti3Al
Author/Authors :
MARC LEGROS، نويسنده , , ALAIN COURET، نويسنده , , DANIEL CAILLARD، نويسنده ,
Issue Information :
دوهفته نامه با شماره پیاپی سال 2006
Pages :
11
From page :
2647
To page :
2657
Abstract :
Several dislocation glide mechanisms are studied in Ti and Ti3Al by means of in situ straining experiments in a transmission electron microscope at various temperatures. The prismatic glide of α titanium occurs by the jerky motion of straight screw a-dislocations subjected to a frictional force. An explanation for the discontinuity in the temperature dependence of the corresponding activation area is proposed, on the basis of the experimentally measured variation of the corresponding dislocation jump length. In Ti3Al, superlattice 2a-dislocations exhibit two different dissociation modes in prismatic planes corresponding to highly different antiphase boundary energies. The properties of these two types of dislocation are compared and discussed. It is shown that the motion of 2c+a superlattice dislocations in pyramidal planes is controlled by a new mechanism: the self-nucleation of small-size obstacles as the result of irreversible atomic displacements. The tension/compression asymmetry observed between type 1 and type 2 pyramidal planes is finally discussed. C 2006 Springer Science + Business Media, Inc
Journal title :
Journal of Materials Science
Serial Year :
2006
Journal title :
Journal of Materials Science
Record number :
830818
Link To Document :
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