层厚度和应变率对铜-金复合纳米线力学性能影响的模拟研究

采用分子动力学模拟方法, 研究了层厚度和应变率对铜-金多层复合纳米线在均匀拉伸载荷下力学性能的影响, 并分析了铜-金位错成核机理. 研究结果表明, 随着铜-金层厚度的增加, 复合材料的屈服强度也随之增大; 高应变率时复合材料的力学性能比低应变率时要强, 低应变率的塑性形变主要是位错运动和孪晶形变, 而高应变率主要以单原子运动为主, 表现出了非晶化. 该研究对制备高性能的多层复合材料提供了一定的理论依据.

Effects of layer thickness and strain rate on mechanical prop erties of copp er-gold multilayer nanowires

Effects of individual layer thickness and strain rate on the mechanical behavior of copper-gold multilayer nanowires as well as the dislocation nucleation mechanism under a uniform tensile loading are investigated using molecular dynamics method. Simulations indicate that the highest yield strength increases with the increase of the individual layer thickness. Furthermore, the result also shows that the mechanical properties in the tensile process at different strain rates are dramatically different from each other, where the dislocation motion and twinning deformation are at a lower strain rate, while the individual atoms are at a higher strain rate for leading to amorphization. The general conclusions derived from this work can provide a guideline for the design of high performance multilayer composite materials.