Font Size: 

A numerical investigation into the reflection and transmission of axial waves at stepped nanorods is presented. A scale dependent doublet mechanics theory is used in the analysis. The main difference of the doublet mechanics from other scale dependent models (stress gradient, strain gradient and couple stress theories) is its direct dependence of the micro/nano structure of the solid. Scale parameter is directly related to atomic structure of the material in doublet mechanics theory and it is assumed as carbon-carbon bond length in the present study. However, identification of scale parameters in other scale dependent theories is difficult compared to doublet mechanics theory. Governing equations of stepped nanorods are derived using the Hamilton Principle. The numerical results predicted by doublet mechanics are shown and compared with the classical elasticity for stepped nanorods. For validation, wave frequencies obtained by using doublet mechanics are compared with the experimental results for graphite. Obtained solutions show that doublet mechanics gives reasonable results when compared with other classical continuum and scale dependent theories at the nano length scale. The advantages and physical basis of doublet mechanics are discussed in detail.