FORMATION OF DEFORMATION TWINS IN TiAl

摘要

Mechanisms have been proposed for the formation of fault-pairs in the L1_0 structure that involve both ordinary and super glide dislocations having co-planar Burgers vectors. These fault-pairs could serve as two-layer embryonic twins and twin thickening may occur by the coalescence of fault-pairs located at different levels within a slip band. The crystallorgaphies of deformation twins are examined in as-processed TiAl by transmission electron microscopy and are correlated with that of slip required for the formation of Fault-pairs.