Cu/Nb纳米多层膜延性及其断裂行为  

Ductility and fracture behavior of Cu/Nb nanostructured multilayers

作　　者：张欣[1] 张金钰[1] 牛佳佳[1] 雷诗莹[1] 刘刚[1] 孙军[1] 

机构地区：[1]西安交通大学金属材料强度国家重点实验室,西安710049

出　　处：《中国有色金属学报》2011年第6期1404-1408,共5页The Chinese Journal of Nonferrous Metals

基　　金：国家重点基础研究计划资助项目(2010CB631003);国家自然科学基金资助项目(50971097)

摘　　要：通过单轴拉伸试验研究恒定调制周期的聚酰亚胺基体Cu/Nb纳米金属多层膜的延性对调制比的依赖性,并采用聚焦离子束/扫描电子显微镜(FIB/SEM)截面定量表征技术深入分析多层膜的异质约束效应对断裂行为的影响。结果表明:随着调制比的增加,多层膜的延性单调减小,出现由剪切型向张开型断裂模式的转变。当调制比小于某一临界值时,调制周期越小,多层膜延性越高;反之,则多层膜延性越差。这是由于软相Cu层对脆相Nb层中萌生的微裂纹扩展的约束作用。The dependent of ductility of polyimide-based Cu/Nb nanostructured metallic multilayers with constant modulation period on the modulation ratio was investigated by uniaxial tensile testing.The heterogeneity restriction effect of the multilayers affecting the fracture behavior was further studied through quantitative focused ion beam（FIB） and scanning electron microscope（SEM） cross-section characterization technique.The results show that the ductility of multilayers decreases with increasing modulation ratio,and the fracture mode transforms from opening to shear mode.When the modulation ratio decreases to less than a critical value,the ductility increases with decreasing modulation period.When the modulation ratio is larger than the critical value,the ductility decreases with decreasing modulation period.This can be attributed to the ductile Cu layer that can arrest the microcracks initiated in the brittle Nb layer.

关 键 词：纳米金属多层膜 延性 断裂行为 调制比 

分 类 号：TG113[金属学及工艺—物理冶金]