Polycrystalline specimens of this phase were deformed in compression at temperatures of between 250 and 700C. The dislocation structures were examined by using transmission electron microscopy. It was found that this phase was brittle at temperatures below 250C, but was ductile at temperatures above 300C. Most of the dislocations which were activated by an applied stress had Burgers vectors which were parallel to <111> over the temperature range that was studied. The Burgers vectors of dislocations that were introduced at 300 and 450C were a/2<111>, where a was equal to 0.9005nm. On the other hand, the Burgers vectors of dislocations which were introduced at temperatures above 600C were either 2a/3<111> or a/3<111>. The activation volume at low temperatures (300 and 450C) was estimated to be about 0.2nm3, and it was suggested that the dislocations which were activated at low temperatures were dissociated into partials whose Burgers vector was 1/6<111>.

The Mechanical Properties And Dislocation Structure of the γ Intermetallic Phase in the Fe-Zn System. M.H.Hong, H.Saka: Philosophical Magazine A, 1996, 74[2], 509-24