纳构件加工后的力学特性

"采用分子动力学模拟的方法,运用镶嵌原子模型,研究了经过刻划后的单晶铜纳构件在不同拉伸速度条件下的力学行为. 通过原子位图、缺陷原子透视图、径向分布函数及应力-应变关系研究加工后纳构件在拉伸负载作用下的变化特性,并与理想单晶铜纳构件进行对比分析．模拟结果表明,加工后的纳构件的屈服强度较理想纳构件的屈服强度有明显下降,屈服强度随着刻槽深度的增加而下降,而且屈服强度对刻槽方向和拉伸速度敏感;纳结构在拉伸负载作用下,其应力应变关系出现了双峰形式,即工作硬化现象,二次屈服后表现为Z字形逐波下降形式．刻划深度、刻划

Mechanical Properties of Machined Nanostructures

"Three-dimensional molecular dynamics simulations have been carried out to predict the mechanical properties of a single crystalline copper with different scratching depths and no defects by embedded-atom method potential respectively. The mechanical properties for nanostructure with no defects and machined groove are investigated by various strain rates, scratched depths and scratching directions. Through the visualization technique of atomic coordination number, the onset and movement of defects in workpiece such as dislocations are analyzed under tensile loads. Work-harden formation, recrystallization behavior and the properties of rupturing process of nanostructure are exhibited at the atomic view. The relation between stress and the onset and evolvement of defects in specimen is analyzed for fundamental understanding the mechanical properties of nanostructure."