Published online by Cambridge University Press: 26 February 2011
The deformation behavior of Ni3Al alloys with various chemical compositions and subjected to different heat treatments were in-situ observed in SEN. Moreover, in-situ observations of slip trace are supplemented by the direct observation of dislocation arrangements by TEM. In boron-doped Ni3Al alloys it is shown that close to the grain boundary there exists a thin slip transition region, within which slip lines are reoriented or other slip systems are operated to produce a local strain accommodation and to relax the stress concentration at grain boundaries. However, boron-enhenced ductility is seriously affected by alloy stoichiometry, the addition of a tertiary alloy element and heat treatment, etc.