The identity of the dislocations which contributed to the plastic deformation of polycrystalline MoSi2 when compressed at 1400C was determined using transmission electron microscopy. It was confirmed that dislocations with Burgers vectors lying parallel to <100> and <111> were activated in response to the applied stress. In addition, the deformation microstructure was characterized by the presence of networks containing dislocations having Burgers vectors parallel to <100], <110] and <111>. It was shown that dislocations having Burgers vectors parallel to <111> were dissociated. A simple explanation was developed in order to account for the dissociation of particular dislocations and, on the basis of this model, the dissociation was represented by:

½<111>  ½<111>+SISF+¼<111>

where SISF was a superlattice intrinsic stacking fault. The energy of the latter was estimated, from the separation of the partial dislocations, to be about 261mJ/m2.

Dislocation Dissociation in the Intermetallic Compound MoSi2. D.J.Evans, S.A.Court, P.M.Hazzledine, H.L.Fraser: Philosophical Magazine Letters, 1993, 67[5], 331-41