Strain development in a single phase polycrystalline B2 RuAl alloy was studied at the local microstructural scale using a high-resolution surface displacement mapping technique. Significant heterogeneity of straining was observed within individual grains and among neighboring grains. Strains accumulated in a self-similar manner at the grain scale during stepped loading experiments. Schmid factors for the possible slip systems were calculated using grain orientation data collected by electron back-scattered diffraction. Considering the two major active slip systems identified in RuAl, i.e. <100>{110} and <110>{110}, activity on the <110>{110} slip system dominated the local straining behavior within the grains investigated. Complementary transmission electron microscopic dislocation analyses were performed by removing foils from targeted representative grains using a focused ion beam system. A higher density of <110> dislocations compared to <100> dislocations were observed in the most heavily strained grain.

Grain-Scale Strain Mapping for Analysis of Slip Activity in Polycrystalline B2 RuAl. A.Wu, M.De Graef, T.M.Pollock: Philosophical Magazine, 2006, 86[25-26], 3995-4008

Figure 4

Diffusivity of Cu on β-Ta Surfaces