爆炸载荷下纳米晶铜晶粒度分布及影响因素研究

 采用爆炸动态加载使粗晶铜发生高应变率塑性大变形的方法制备了纳米晶铜。利用X射线衍射法对其晶粒度进行了检测，借助于LS-DYNA3D非线性有限元程序对试样变形过程进行了数值模拟，在此基础上对应变和应变率进行了统计，分析了宏、细观应变对晶粒细化程度的影响。结果表明：采用爆炸加载法可制备出纳米晶铜，平均晶粒度范围可有效控制在100 nm以内；爆炸加载过程中应变率高达10⁴ s^-1，应变的提高有利于晶粒细化；在爆炸加载方向晶粒度成不均匀分布。

Study on the Grain-Size Distribution Rule and Influence Factors of Nanocrystalline Copper Fabricated under Explosive Loading

Nanocrystalline copper was fabricated by severe plastic deformation of coarse-grained copper at high strain rate under explosive loading. The average grain size of the samples was tested by X-ray diffraction  analysis, and the deformation process was simulated recur to LS-DYNA3D finite element program. The influence of strain on the grain refining were analyzed quantitatively. The results show that it is feasible to fabricate nanocrystalline copper by explosively dynamic plastic deformation of coarse-grained copper and the grain size of the NC copper can be controlled less than 100 nm, the higher strain is beneficial to the grain  refining, and the distribution of the grain size is not uniform along the loading direction.