Shear punch testing and fracture toughness of bulk nanostructured silver

The quantitative effects of surface finish on the mechanical behavior of flaw-free bulk nano-Ag samples consolidated by a dynamic process were studied. The results show that the samples possessing a surface roughness of 30 and 12 nm had a converted yield strength of 310 MPa, ultimate tensile strength of 320 MPa and ductility of 15%, while the samples possessing a surface roughness of 267 nm exhibited a brittle behavior and a reduction in strength of 35% in comparison to the smoother surfaces. Dimples were observed for the samples exhibiting plasticity, while an intergranular pattern was identified for the brittle materials.