Problem 2 1 Coincidence site lattice boundary CSL

Problem 2 -1 Coincidence site lattice boundary CSL boundary: one of the special high-angle boundary The coincidence site lattice is repeated partially self-coincident points of overlapping two lattices in a certain geometrical position(axis-angle pair), and the CSL boundary is the boundary between grains with CSL relation. Thus, CSL boundary usually have lots of common atoms in both grains and low grain boundary energy. �� #: the reciprocal density of coincident lattice sites(not atoms) and denoted the CSL boundary. *�� 1: some papers use it as a low-angle grain boundary **�� 3: twin boundary in cubic system �� 5 Polycrystalline silicon, EBSD, J. Mater. Sci. (2014) 49; 4938 -4945 Cubic crystal, <100>36. 9° Kyung-yeon Doh kydoh 92@postech. ac. kr

Problem 2 -2 General multicomponent form of solute composition in surface Gibbs free energy of i component Bulk: *equilibrium: *assumption: Surface: where and Result 1: *unity: X 1+…+Xn = 1 Result 2: Kyung-yeon Doh kydoh 92@postech. ac. kr

Problem 2 -3 Abnormal grain growth Main features of AGG 1. Huge size 2. Island grains Monte Carlo method with a modified Potts model Simulation conditions 1. Energy 2. Mobility Lattice site Orientation Energy Attempting # Probability Fig. 2 Image of MC simulation Main cause Fig. 1 Image of Abnormal grain growth Fig. 3 Effect of anisotropic GB energy • • Solid-state wetting by anisotropy of GB energy Normal grain growth inhibiting by precipitations Fig. 4 Effect of precipitation and sub-boundary Kyung-yeon Doh kydoh 92@postech. ac. kr