Experimental studies, using electron back-scattering diffraction, were made of the effect of composition, texture and processing upon the nature of grain boundaries in the B2 compound. An alternative method, for calculating the unbiased fraction of grain boundaries having a given nature, was proposed which was based upon the grain boundary surface area. It was shown that the proposed method gave different results to those of classical methods that were based upon the counting of grain-boundary segments. It was found that the fraction of low-angle boundaries increased with increasing percentage of the <100> texture and, to a lesser extent, the <111> texture; up to an upper limit of 20%. The fraction of so-called special grain boundaries (Σ = 3 to 29) appeared to be independent of the fraction of <100> texture. Shock-loading and annealing could increase the fraction of low-angle boundaries to between 0.90 and 0.97. The fraction of low-angle boundaries appeared to increase almost linearly, up to a limit of about 20%, upon decreasing the grain size from 400 to 100μm. At grain sizes below 100μm, the fraction of low-angle boundaries appeared to be independent of the grain size. The fraction of special grain boundaries did not exhibit any dependence upon grain size.

Grain Boundary Character Distribution in B2 Intermetallics. J.Bystrzycki, R.A.Varin, M.NoweIl, K.J.Kurzydlowski: Intermetallics, 2000, 8[9-11], 1049-59