Surface Effects On A Cylindrical Core-shell Structures With An Imperfect Interface Subjected To P/SV Wave

With the rapid development of nanotechnology,nano-components and nano-materials will be widely concerned and applied.At the nano-scale,due to the obvious increase the ratio of surface area to the volume effect and surface effect of nano-components and nano-materials are significant,making their mechanical properties significantly different from the material properties under the macroscopic conditions.Therefore,in this scale,when elastic waves encounter obstacles such as holes or inclusions in the process of propagation,they will interact with such obstacles,and the effect is obviously different from that under macro conditions.And in the practical cases,the interface is not always perfect and smooth,they always have a certain form of defects.Based on the surface elastic theory and classical elastic theory in this thesis,the scattering of P/SV waves by cylindrical core-shell structures with non-ideal interfaces at the nanometers is studied.The influence of different parameters such as surface parameter and spring coefficient on dynamic stress concentration coefficient is discussed.The main research methods are as follows:(1)The scattering problem of different wave fields is studied by wave function expansion method.(2)The non-ideal interface is simulated by the linear spring model,and different boundary conditions are given.The results show that at the nanometers,the surface parameters have significant effects on the stress concentration at the interface.The smaller the spring coefficient is,the stronger the interface imperfection is,and the stronger the stress concentration at the boundary is.When the spring coefficient reaches a certain value,it is almost close to the dynamic stress value under the ideal interface.The DSCF are obviously different under different incident wave frequencies.