Deformation of the - and 2-lamellae of this alloy during room-temperature and 800C tensile loading was studied by means of transmission electron microscopy. A marked change in the plastic behavior of the latter phase was detected between these temperatures, whereas the deformation mechanisms which were active in the  phase remained the same at both temperatures. At room temperature, plasticity of the 2 phase occurred only locally via the prism-plane slip of dislocations with Burgers vectors that were parallel to <11•0>, where cross-lamellar twins in the -plane impinged upon the /2 interface. At 800C, a more homogeneous plastic behavior of the 2 phase resulted from the slip and climb activity of dislocations with Burgers vector components that were parallel to <11•0> and parallel to both <11•0> and [00•1]. The increased contribution, of 2-lamellae, to strain accommodation at 800C coincided with a change in the predominant fracture mode.

J.M.K.Wiezorek, P.M.DeLuca, M.J.Mills, H.L.Fraser: Philosophical Magazine Letters, 1997, 75[5], 271-80