This paper assesses the contribution of grain boundary triple junctions to the driving force for grain growth and the so-called energetic effect of boundary junctions on grain growth in nanocrystalline materials. The first measurement of grain boundary line tension allows the quantitative estimation of the fraction of the driving force due to boundary triple junctions. For polycrystals with a grain size of the order of some 50nm, it was comparable with the driving force arising from grain boundaries.

Thermodynamics and Kinetics of Grain Boundary Triple Junctions in Metals: Recent Developments. G.Gottstein, L.S.Shvindlerman, B.Zhao: Scripta Materialia, 2010, 62[12], 914-7