Influence of Surface Effects on Bending and Buckling of Nanowires

摘要

The static bending and longitudinal stability of nanowires under pressure in a liquid or gas are considered. Two surface effects are taken into account. The first effect is induced by the difference in the elastic properties of a thin surface layer and the bulk of the material. The effective tensile and flexural stiffness can be higher or lower than the conventional stiffness depending on the material. The second effect is due to the action of overpressure on the circular lateral surface of the wire and the difference in the areas of the convex and concave sides of the surface arising under bending. This effect manifests itself the more strongly, the greater the ratio of pressure to the modulus of elasticity of the material and the wire length to its diameter. These effects are determined by dimensionless parameters. It has been established that a buckling of wire may occur under the action of the second effect. A possible method for determining the dimensionless parameter, which determines the differences in the elastic properties of a thin layer near the surface and the bulk material, is proposed.