The boundary misorientations in powder-in-tube samples were determined by using electron back-scattering Kikuchi diffraction and X-ray micro-diffraction techniques. Data on over 113 spatially correlated grains (227 grain boundaries) showed that over 40% of the boundaries were  = 1 or low-angle (less than 15). In addition, 8% of the boundaries were within the Brandon criterion for coincidence site lattices ( larger than unity and less than 50). Grain boundary texture maps, deduced from electron microscope image and orientation data, revealed the existence of percolative paths between low-energy boundaries.

A.Goyal, E.D.Specht, D.M.Kroeger, T.A.Mason, D.J.Dingley, G.N.Riley, M.W.Rupich: Applied Physics Letters, 1995, 66[12], 2903-5