Effect of finite boundary junction mobility on the growth rate of grains in 3D polycrystals

Abstract

With decreasing grain size, grain boundary junctions become increasingly important for microstructure evolution. We show that the effect of a limited mobility of triple junctions on the growth rate of polycrystals can be implemented in theories of three-dimensional (3D) grain growth. Respective analytical relations are derived on the basis of the average n-hedra approach introduced by Glicksman to describe the volume rate of change of 3D grains in a polycrystalline aggregate under the impact of a limited triple junction mobility. The theoretical predictions were compared to network-model computer simulations, and good agreement was obtained.

Keywords:

• grain growth
• finite mobility
• triple junction
• MacPherson–Srolovitz equation
• n-hedra

Acknowledgements

Financial assistance from the collaborative research centre of the Deutsche Forschungsgemeinschaft (DFG) SFB 761 “Stahl ab-initio” and through project Go335 of the DFG is gratefully acknowledged. We appreciate the financial support of the cooperation through the DFG Grant RUS113/846/0-2(R) and the Russian Foundation of Fundamental Research (Grant DFG-RRFI 09-02-91339). Discussions with Prof. P.R. Rios during his stay at the IMM are gratefully acknowledged.