Research On Electromagnetic/Mechanical Comprehensive Performance Design Technology Of Slotted Honeycomb Absorbing Structure

Honeycomb absorbing structure has the excellent characteristics of light weight,excellent impact resistance and electromagnetic absorption,so it is widely used in aerospaces and other military fields.In order to meet the multi-functional engineering application of honeycomb absorbing structure,the passive electronic components are“perfect combination” with composite materials so as to integrate the thermal function,electronic function and radiation shielding efficiency into the inherent bearing parts of the spacecraft.So that the spacecraft has a qualitative flight in the aspects of lightweight and multi-function.The key problem of the design is to comprehensively evaluate the electromagnetic/mechanical properties of the honeycomb structure after slotting,so the reasonable slot design can not only reduce the weight of the honeycomb structure to meet the engineering application but also have good electromagnetic/mechanical properties,which is of great significance to the multifunctional design of the honeycomb structure.This paper designed a slotted honeycomb absorbing structure in connection with the problems or deficiencies.Traditional hexagonal honeycomb is mainly studied and then the honeycombs is slotted regularly and irregularly.Through the combination of experimental testing and simulation,to analyze the influence and law of the slotting on the electromagnetic and mechanical properties of the honeycomb absorbing structure,which is plays a guiding role in the design of multifunctional of honeycomb absorbing structure.The paper main work is as follows:(1)The influence of slot basic parameters on mechanical properties of Nomex honeycomb compression and three-point bending was investigated.The deformation mode and mechanical parameters of Nomex honeycomb are obtained through flat compression experiments,and used to verify the accuracy of the finite element simulation model.Then the simulation model was divided into concentrated slotting and decentralized slotting,and the influences of the change of slotting size in three directions on mechanical parameters of Nomex honeycomb were investigated respectively.Also the effects of the size of slots on the three-point bending performance is analyzed.The results show that the deformation of concentrated slotting and decentralized slotting are similar of whole honeycomb.In the direction of L and W,the mechanical parameters of honeycomb decrease with the increase of slot opening.In the T direction,the elastic modulus and yield strength of honeycomb remained unchanged with the increase of the concentrated slotting.The simulation of three-point bending of Nomex honeycomb shows that with the increase of slot size,the peak load decreases,and the bending performance decreases.(2)To explore the comprehensive influence of regular slot on electromagnetic and mechanical properties of honeycomb absorbing structures.The effect of regular slot on the mechanical properties of honeycomb was investigated by flat compression experiment and finite element simulation.Through microwave anechoic chamber test and electromagnetic simulation calculation,the influence of regular slot on the electromagnetic properties of honeycomb was analyzed.The results show that the displacement load curve of the honeycomb absorbing structure after slotting is the same as that of unslot honeycomb absorbing structure divided into three stages.With the increase of slotting rate,the elastic modulus,yield strength and platform stress are gradually decrease.Electromagnetically,the average difference of RCS is less than 0.5d B after regular slotting,and there is basically no effect on the absorbing performance of the honeycomb absorbing structure.The RCS curve of slotted honeycomb with circular plate changes gently,but the overall absorbing performance is not as good as that of quadrilateral honeycomb.(3)To explore the comprehensive influence of irregular slotting on electromagnetic and mechanical properties of honeycomb absorbing structures.The research method is similar to regular slotting,but the shape of the upper and lower slot is different.The consequence show that the displacement load curve is divided into three stages in mechanics.But when one layer has the largest slot size,the change of the slot size of the other layer will not affect the modulus of elasticity and yield strength.In electromagnetic aspect,the mean difference of RCS is within 0.89 dB for different width slots,and irregular slot has no effect on the electromagnetic performance of honeycomb absorbing structure.