Abstract: In order to develop a novel vehicular armor plate against radar surveillance systems and blast attack harming occupants,by adopting the glass fiber composite,the functionally-graded polyurethane foams filled with multiwalled carbon nanotubes ( MWCNT) and the carbon fiber composite to respectively make the top surface,the core and the back surface,a novel sandwich plate is designed,which can absorb electromagnetic ( EM) waves and attenuate the shock wave transmission.Then,the analytical models of the EM reflection and the shock wave transmission are developed for the novel structure,and the effects of the gradient pattern and thickness of each dielectric layer on the EM reflection coefficient and the shock wave transmission coefficient are investigated.Moreover,the NSGA-Ⅱ algorithm is used to conduct a multi-objective optimization of structure parameters of armor plate.The results show that,after the optimization,the electromagnetic wave reflection coefficient and shock wave transmission coefficient of the novel structure decrease respectively by 94.58% and 4.35%,which means that the EM absorbing ability and shock wave attenuation ability of the novel structure are both excellent.

Key words: electromagnetic waves, shock waves, polyurethane, multi-walled carbon nanotubes, functionallygraded materials, sandwich structure, multi-objective optimization