Scale-dependent fracture mode in Cu–Ni laminate composites

Abstract

Fracture behavior of Cu–Ni laminate composites has been investigated by tensile testing. It was found that as the individual layer thickness decreases from 100 to 20 nm, the resultant fracture angle of the Cu–Ni laminate changes from 72° to 50°. Cross-sectional observations reveal that the fracture of the Ni layers transforms from opening to shear mode as the layer thickness decreases while that of the Cu layers keeps shear mode. Competition mechanisms were proposed to understand the variation in fracture mode of the metallic laminate composites associated with length scale.

Keywords:

• fracture
• nanolaminate
• length scale
• interfaces

Acknowledgements

This work was supported by the National Natural Science Foundation of China (Grant Nos. 50971125 and 50890173), the China-Australia Special Fund for Science & Technology Cooperation (Grant No. 50811120106), and the National Basic Research Program of China Grant No. 2010CB631003.