Study On The Electromagnetic And Mechanical Properties Of GNPs Modified Resin-coated Honeycomb Core Composite Absorbing Structures

Lightweight and high-strength advanced absorbing structures with composites are an important structural form for aircraft structures with integrated load-bearing ability and multi-functions,which is of great significance for reducing the weight of airframes and improving the quality of structural design.The Graphene Nanoplates(GNPs)modified resin coated honeycomb core composite absorbing structure is a novel form of absorbing structure with composites.It can not only make the most of the excellent electromagnetic properties of GNPs modified resin but also construct multiple loss paths relying on the unique multi-wall structure of hexagonal honeycomb.It is expected to be a broadband absorbing and efficient load-bearing structure.Moreover,it is a promising composite structure with integrated wave absorption and load-bearing,which is significant for promoting the development of composite materials with integrated loadbearing ability and multi-functions for aircraft structures.The electromagnetic and mechanical properties of the wave absorbing structure constructed by honeycomb core with GNPs modified resin coated are investigated using a cross-scale analysis method in this research.Firstly,on the nano-scale,a random distribution configuration model for warped GNPs was developed.Based on the theoretical model of the electrical properties of the GNPs interface,the far-field matching effective medium theory was applied to predict the effective complex permittivity for warped GNPs modified resin composites,which is dependent on the filler volume fraction and electric field frequency.In addition,the influence of statistical distribution patterns of warped GNPs,the effect of warping characteristics,and the interface property on the predicted results were investigated.Then,the effective elastic parameters of the composites were predicted via the mechanics approach on meso-scale.Secondly,on the macroscale,the electromagnetic analysis model for the wave absorbing structure constructed by honeycomb core with coated GNPs modified resin was established.The influence of the GNPs content,the structure parameters,and the electromagnetic wave incidence properties on the wave absorbing performance of the structure were analyzed based on the finite element numerical method.The mechanical elastic properties of the coated honeycomb sandwich structure with typical parameters were also explored.Finally,the electromagnetic analysis model for GNPs modified resin coated honeycomb core composite stealth bullet wing was developed.Then,the influence of electromagnetic wave polarization mode,incident direction,frequency range,GNPs volume fraction,and coating thickness on the forward RCS(radar cross section)of the stealthy wing was investigated.This study preliminarily reveals the intrinsic wave absorption mechanism of GNPs modified resin composites.Important conclusions with reference values were obtained by systematically discussing the factors influencing the wave absorption performance of GNPs modified resin coated honeycomb sandwich structures.They will provide a theoretical basis for the design of integrated wave absorption and load-bearing composite structures.