ナノロッドの引張試験手法の開発

抄録

We develop a new test method for evaluating tensile properties of nano-mateirals and apply it to a single crystalline gold nanorod with a square section of 189nm. The nanorod, which is carved out of a bulk material by focused ion beam processing, is mounted on a lozenge-shaped silicon frame and is pulled by a compressive load on the top face of the frame. Although the applied load increases monotonically in the early stages of deformation, it drops rapidly at a certain displacement. In-situ TEM observation indicates that the rapid decrease of applied load is due to crystallographic slip generation in the nanorod. The critical resolved shear stress on the primary slip system at yielding is evaluated to be 325.8MPa, which is about 600times larger than that of bulk. When the tensile elongation becomes large, the nanorod shows necking and isotropic plastic behavior independent on crystalline structure.