论文标题
在单晶触觉的高速压缩下储能存储
Energy storage under high-rate compression of single crystal tantalum
论文作者
论文摘要
当材料塑性变形时，大多数机械工作被散发为热量，而转化为热量的塑料工作的比例称为泰勒 - Quinney系数（TQC）。大规模的分子动力学模拟是对单晶塔塔尔的高应变速率压缩进行的，并报告了所得积分和差异TQC值，最高为1.0的真实菌株。提出了一个现象学模型，该模型是针对材料中存储的能量作为时间的函数，该函数的变形条件定义了该能量的渐近极限。该模型合理地描述了TQC值对1.0的收敛，并没有直接解决热机械转化的物理性质。相反，这是在第二个更详细的模型中开发的，该模型可以准确地说明了两个不同的贡献，其中一个是越来越多的位错网络，另一个是移动位错留下的点缺陷碎片。发现点缺陷碎片的贡献被发现落后于错位网络的贡献，但在此处考虑的高速拉力条件下要实质性。
When a material is plastically deformed the majority of mechanical work is dissipated as heat, and the fraction of plastic work converted into heat is known as the Taylor-Quinney coefficient (TQC). Large-scale molecular dynamics simulations were performed of high strain rate compression of single-crystal tantalum, and the resulting integral and differential TQC values are reported up to true strains of 1.0. A phenomenological model is proposed for the energy stored in the material as a function of time with an asymptotic limit for this energy defined by the deformation conditions. The model reasonably describes the convergence of TQC values to 1.0 with increasing plastic strain, but does not directly address the physical nature of thermo-mechanical conversion. This is instead developed in a second more detailed model that accurately accounts for energy storage in two distinct contributions, one being the growing dislocation network and the other the point defect debris left behind by the moving dislocations. The contribution of the point defect debris is found to lag behind that of the dislocation network but to be substantial under the high-rate straining conditions considered here.
