Fabrication of Nanowire Specimen with Controlled Shape and Crystallographic Orientation and Development of Tensile Testing Method based on Mechanical Design of Specimen

提出了一种新的拉伸测试方法，并将其应用于正方形截面为189 nm的单晶金纳米线。纳米线安装在一个菱形硅框上，受到框架顶面的压缩载荷的拉动。虽然外加载荷在变形初期单调增加，但在某一位移时迅速下降。透射电子显微镜的原位观察表明，快速下降是由于晶体滑移的产生。屈服时的临界分辨剪应力为325.8 Mpa，约为块材的600倍。

A new tensile test method was developed and was applied to a single crystalline gold nanowire with a square section of 189 nm. The nanowire, which was mounted on a lozenge-shaped silicon frame, was pulled by a compressive load on the top face of the frame. Although the applied load increased monotonically in the early stages of deformation, it dropped rapidly at a certain displacement. In-situ TEM observation indicated that the rapid decrease was due to crystallographic slip generation. The critical resolved shear stress at yielding was evaluated to be 325.8 MPa, which was about 600 times larger than that of bulk.