title: Transformation of the deformation mechanism from dislocation-mediated slip to homogeneous slip in silver nanowires.
abstract: The tensile deformation behavior of silver (Ag) wires with nanometer widths (nanowires (NWs)) was observed by in situ high-resolution transmission electron microscopy combined with subnanonewton force measurements. The Young's modulus, strength, and critical shear stress of the Ag NWs were investigated based on the mechanics of materials at the atomic scale. It was found that when the minimum cross-sectional area of the NWs decreased to less than approximately 3.2 nm2, the critical shear stress increased with a decrease in the area. In addition, when the minimum cross-sectional area decreased to less than approximately 0.5 nm2 before fracture, the critical shear stress reached 0.96 GPa, which exceeded the theoretical shear stress of bulk Ag crystals on {1111} along (110). The present results indicate that the deformation mechanism of Ag NWs transformed from dislocation-mediated slip to homogeneous slip. Therefore, it can be concluded that size reduction to nanometer scale leads to a considerable increase in strength.
authors: Division of Materials Science, Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan.
authors: Jianbo
authors: J
authors: Feng
authors: Tokushi
authors: T
authors: Kizuka
mesh_terms: D019245:Compressive Strength; D003198:Computer Simulation; D055119:Elastic Modulus; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D008956:Models, Chemical; D033081:Shear Strength; D012834:Silver / Q000737:chemistry*; D013718:Tensile Strength
chemical_list: D012834:Silver