Boosting electromagnetic wave absorption of Ti_(3)AlC_(2) by improving effective electrical conductivity  

作　　者：Kai-Yu Guo Lin Chen Guan-Jun Yang 

机构地区：[1]State Key Laboratory for Mechanical Behavior of Materials,School of Materials Science and Engineering,Xi’an Jiaotong University,Xi’an 710049,China

出　　处：《Journal of Advanced Ceramics》2023年第8期1533-1546,共14页先进陶瓷（英文）

摘　　要：Electromagnetic wave-absorbing(EMA)materials at high temperatures are limited by poor conduction loss(L_(c)).However,adding conductors simultaneously increases the conduction loss and interfacial polarization loss,leading to a conflict between impedance matching(Z_(in)/Z_(0))and electromagnetic wave loss.This will prevent electromagnetic waves from entering the EMA materials,finally reducing overall absorbing performance.Here,the effective electrical conductivity(σ)is enhanced by synchronizing particle size and grain number of Ti_(3)AlC_(2) to increase the conduction loss and avoid the conflict between the impedance matching and the electromagnetic wave loss.As a result,the best-absorbing performance with an effective absorption bandwidth(EAB)of 4.8 GHz(10.6–15.4 GHz)at a thickness of only 1.5 mm is realized,which is the best combination of wide absorption bandwidth and small thickness,and the minimum reflection loss(RL_(min))reaches−45.6 dB at 4.1 GHz.In short,this work explores the regulating mechanism of the EMA materials of effective electrical conductivity by simulated calculations using the Vienna ab-initio Simulation Package(VASP)and COMSOL as well as a series of experiments,which provide new insight into a rational design of materials with anisotropic electrical conductivity.

关 键 词：anisotropic electrical conductivity conduction loss(Lc) interfacial polarization loss(LIP) effective electrical conductivity co-optimize impedance matching(Zin/Z0) electromagnetic wave loss 

分 类 号：TB34[一般工业技术—材料科学与工程]