多层混合填充吸波材料的三目标粒子群优化

使用多层结构来离散自由空间到金属衬底之间理想的连续阻抗变化过程是吸波材料设计的重要方 法之一,较多层数的精细结构能够更好地逼近这一连续变化过程以获得更理想的吸波性能,但也会增加工程实现成 本和复杂度。因此,实际工程中往往需要在结构层数和逼近精度等诸多相互矛盾的因素之间寻求平衡。文中采用 石墨烯纳米片(GNS) / 片状羰基铁颗粒(FCI)混合填充的多层吸波材料,在由极化无关的宽带宽角吸波性能、FCI 填 充量以及最终层数这三个指标所张成的三维目标空间中,基于粒子群优化对多层吸波材料进行了优化设计。结果 显示,相比于吸波性能和磁性粒子填充量二维空间中的设计结果,在FCI 填充量仅需增加不到3. 3 wt%的情况下,即 可使所需层数下降50%并保持原有吸波能力的98%;不进行优化的GNS 填充量仅增加0. 6 wt%,层数显著减少,吸 波材料的总厚度降低了14%,综合性能也提高了27. 9%。此外,与其它不同优化策略的系统进行了对比,文中设计 为混合填充吸波材料的多目标优化提供了一定参考。

Tri-objective Design of Multi-layer Hybrid-filled Microwave Absorbing Materials Based on Particle Swarm Optimization

Using multi-layer structure to discrete the continuous impedance changing process from free space to metal substrate is one of the important methods in the design of microwave absorbing materials. More layers can approach more accurate approximation of this continuous impedance changing process and achieve better absorbing properties, but it will lead to an obvious increase of cost and complexity for engineering implementation. Therefore, it is of importance to find a balance between these contradictory factors. In this paper, the multi-layer microwave absorbing material filled with graphene nanosheet (GNS) / flake carbonyl iron particles (FCI) is taken as the main object in this paper. Then, based on particle swarm algorithm, the optimization design is carried out in the three-dimensional objective space composed of polarization-independent broadband and wide-angle microwave absorbing performance, FCI filling amount and the number of layers. The results show that, compared with the design results in the two-dimensional space of microwave absorption performance and magnetic particle filling capacity, the required number of layers can be reduced by 50% and the microwave absorption capacity can be maintained by more than 98% with only a 3. 3 wt% increase of the FCI filling amount. Meanwhile, the GNS filling amount, which is not an optimization object, counts a mere 0. 6 wt% increase, and thanks to the significant reduction of the number of layers, the total thickness of the microwave absorbing material is reduced by 14% and the comprehensive performance is improved by 27. 9%. Finally, the systematic comparison with other different optimization strategies also provides a certain reference for the multi-objective optimization of multi-layer hybrid-filled microwave absorbing materials.