纳米晶体材料因表现出了常规材料许多不具备的性能,尤其是优于常规晶体的性能,而倍受人们的普遍关注[1]。如冷变形致密化纳米晶Al的屈服强度和断裂强度分别是同质粗晶Al的12倍和5倍[2]。纳米晶体材料的晶粒尺寸很小,界面占有很高的体积百分比,因此,晶界对纳米材料性能的影响将 Nanocrystalline materials have attracted the attention of many people due to their many properties that conventional materials do not have, especially superior to conventional ones [1]. For example, the yield strength and the breaking strength of densified nanocrystalline Al are respectively 12 times and 5 times higher than that of homogenous coarse-grained Al [2]. The nanocrystalline material has a very small grain size and a high volume percentage of the interface, so the effect of the grain boundaries on the properties of the nanomaterials