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Measurement of Lattice Displacements at Planar Defects in 2H and 18R Martensites

Published online by Cambridge University Press:  17 March 2004

Adriana María Condó
Affiliation:
Centro Atómico Bariloche (CNEA), 8400 S.C. de Bariloche, Argentina Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina
Francisco Carlos Lovey
Affiliation:
Centro Atómico Bariloche (CNEA), 8400 S.C. de Bariloche, Argentina
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Abstract

A review of transmission electron microscopy studies of planar defects in 18R and 2H martensites in Cu-Zn-Al alloys is presented. The non-basal plane faults observed in the 2H structure, the F1 faults, show two kinds of dislocations at their ends. In contrast, two types of non-basal plane faults are observed in the 18R structure, Fo and Fx faults. The non-basal plane faults can be composed of segments of Fo and Fx faults. Six types of imperfect dislocations appear, depending on the type of basal plane fault ending at the non-basal plane fault. The Burgers vectors of all these dislocations have been determined from the contrast analysis of the images and HREM observations.

Type
Papers from the InterAmerican Congress on Electron Microscopy
Copyright
© 2004 Microscopy Society of America

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