The buckling behavior of nanowires (NWs) has been of focus of attention of the applied mechanics community during the past decade; however, their spatial buckling under the action of both axial force and twisting moment has not been methodically formulated yet. To bridge this scientific gap, the authors eagerly investigate the problem accounting for surface energy based on the Euler–Bernoulli and Timoshenko beam theories. By exploiting these inclusive models, the governing equations are established and solved by the reproducing kernel particle method (RKPM). For simply supported NWs, an exact solution and assumed modes approach (AMA) are also developed. Expectantly, a reasonably good match between the results attained by the RKPM and those of the AMA is achieved. The unstable conditions of the NW under severe axial forces and twisting moments are identified both analytically and numerically for the first time. The influences of the length and radius of the NW on the buckling behavior of the nanostructure are then discussed, and the critical roles of shear deformation and surface energy are methodically displayed and discussed.

在过去十年中，纳米线 (NW) 的屈曲行为一直是应用力学界关注的焦点。然而，它们在轴向力和扭矩作用下的空间屈曲尚未有条不紊地制定。为了弥合这一科学鸿沟，作者热切地研究了基于欧拉-伯努利和铁木辛科光束理论的表面能问题。通过利用这些包容性模型，通过再生核粒子法（RKPM）建立和求解控制方程。对于简支 NW，还开发了精确解法和假定模态法 (AMA)。可以预期的是，RKPM 获得的结果与 AMA 获得的结果之间取得了相当好的匹配。首次在分析和数值上确定了在严重轴向力和扭转力矩下 NW 的不稳定状态。然后讨论了NW的长度和半径对纳米结构屈曲行为的影响，并有条不紊地展示和讨论了剪切变形和表面能的关键作用。