Marquis E A, Hamilton J C, Medlin D L, Léonard F
Sandia National Laboratories, Livermore, California 94551, USA.
Phys Rev Lett. 2004 Oct 8;93(15):156101. doi: 10.1103/PhysRevLett.93.156101. Epub 2004 Oct 4.
We present a combined experimental and theoretical analysis of the structure of finite-sized Sigma 3 [112] grain boundaries in Au. High-resolution electron microscopy shows lattice translations at the grain boundary, with the magnitude of the translation varying along the finite-sized grain boundaries. The presence of this structural profile is explained using continuum elasticity theory and first-principles calculations as originating from a competition between elastic energy and the energy cost of forming continuous [111] planes across the boundary. This competition leads to a structural transition between offset-free and nontrivial grain boundary structures at a critical grain boundary size, in agreement with the experiments. We also provide a method to estimate the energy barrier of the gamma surface.
我们对金中有限尺寸的Σ3 [112]晶界结构进行了实验与理论相结合的分析。高分辨率电子显微镜显示晶界处存在晶格平移，且平移量沿有限尺寸的晶界变化。利用连续介质弹性理论和第一性原理计算解释了这种结构轮廓的存在，其源于弹性能与跨越边界形成连续[111]平面的能量成本之间的竞争。这种竞争导致在临界晶界尺寸处无偏移和非平凡晶界结构之间的结构转变，这与实验结果一致。我们还提供了一种估计γ面能垒 的方法。
