论文标题
α-FE中的双边界可逆性特征
Twin boundary reversibility characteristics in α-Fe
论文作者
论文摘要
了解晶界变形动力学对于设计具有稳定微结构的材料至关重要。通过此任务，使用分子动力学模拟在α-FE中研究了在循环剪切负荷下相干双边界的变形行为，以了解应变振幅和温度的影响。双边界在较低的温度下表现出剪切耦合的迁移以及循环不可逆性特征，并且在较高的温度约为1500 K的较高温度下获得了几乎完美的可逆性。TB表现出比随温度升高的迁移的滑动。观察到与双胞胎迁移相关的应力围绕其平均值波动。这是由双层边界的一层传播引起的，这是通过1/6 <111> = 1/12 <111> + 1/12 <111>在“ \ {” 112“ \}” twin plane上的键入边缘部分脱位。在存在多个平行双纳米线的情况下，发现了完全的双可逆性和复杂的结核病迁移。在较大尺寸的纳米线上观察到双迁移，边界条件和应变速率的正确组合；否则，它是不存在的。剪切应变振幅在抵消双边界中的影响很小。
Understanding the grain boundary deformation dynamics is very crucial to designing materials with stable microstructures. With this quest, the deformation behavior of coherent twin boundary under cyclic shear loading has been studied in α-Fe using molecular dynamics simulations to understand the influence of strain amplitude and temperature. Twin boundary exhibited shear coupled migration along with cyclic irreversibility character at lower temperatures and gained almost perfect reversibility at higher temperatures of around 1500 K. TB exhibited more sliding than migration with an increase in temperature. The stress associated with the migration of twins was observed to fluctuate around its average value. This was caused by layer by layer propagation of twin boundary through the activity of 1/6 <111> = 1/12 <111> + 1/12 <111> type edge partial dislocations on "\{"112"\}" twin plane. Complete twin reversibility and complex TB migration were noticed in the presence of multiple parallel twin nanowires. Twin migration was observed at the larger size nanowires with a proper combination of boundary conditions and strain rates; otherwise, it was absent. The influence of shear strain amplitude in offsetting the twin boundary was found to be minimal.
