Atomic-scale computer simulations were used to study the junctions where 3 boundaries met. The simulated system consisted of a 3-dimensional periodic array of columnar face-centered cubic grains. These grains had 3 different orientations, a common [001] direction, and were rotated by 30º with respect to their neighbours. The interatomic interactions were described by a Lennard-Jones potential. Each simulation cell contained 6 triple junctions, plus the 9 associated symmetrical tilt grain boundaries. The energies of systems of various size were noted during annealing, and after quenching, in order to obtain estimates of the excess energy of the grain boundaries and junctions. For this system, the total energy which was contributed by the triple junctions was negative. This conclusion was consistent with experimental data on high-purity Co.

Excess Energy of Grain-Boundary Trijunctions - an Atomistic Simulation Study. S.G.Srinivasan, J.W.Cahn, H.Jónsson, G.Kalonji: Acta Materialia, 1999, 47[9], 2821-9