An identical Σ = 5 (310)-[001] symmetrical tilt grain boundary was fabricated in 3 different body-centered cubic metals (Nb, Mo, Ta), by means of ultra-high vacuum diffusion bonding, and the atomic structure was studied by using high-resolution transmission electron microscopy. The atomic structure was also predicted by atomistic simulation, using potentials developed within the framework of the model generalized pseudopotential theory for the same 3 metals. These potentials were an example of a new class of interatomic potential that incorporated angularly dependent d-state interactions. These models of interatomic interactions were expected to be applicable to simulations of the central transition body-centered cubic metals, due to the directional nature of the d bonding. Methods were developed for quantitative measurement of the grain-boundary structure from experimental observations, and good agreement with theory was usually found. However, grain-boundary defects appeared to be more common than was first supposed; thus complicating the analysis. Nevertheless, the experiments appeared to confirm the predictive power of the new interatomic potentials for simulating crystal defects in body-centered cubic metals.

The Rigid-Body Displacement Observed at the Σ = 5, (310)-[001] Symmetrical Tilt Grain Boundary in Central Transition BCC Metals. G.H.Campbell, M.Kumar, W.E.King, J.Belak, J.A.Moriarty, S.M.Foiles: Philosophical Magazine A, 2002, 82[8], 1573-