溶解乳化法制备SBS包覆FeSiAl片状吸收剂的微波电磁性能  

Electromagnetic properties of FeSiAl flaky absorbents coated with SBS by a dissolving-emulsifying process

作　　者：马国庆 陈亮[1] 崔正明 李维[1] 官建国[1] MA Guoqing;CHEN Liang;CUI Zhengming;LI Wei;GUAN Jianguo(State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]武汉理工大学材料复合新技术国家重点实验室,武汉430070

出　　处：《材料工程》2022年第2期111-117,共7页Journal of Materials Engineering

基　　金：国家自然科学基金项目(51577138)。

摘　　要：片状FeSiAl吸收剂低频磁性能优异,但复介电常数大、阻抗失配严重,导致难以兼顾高频吸波性能。通过将有机高分子溶解、混合、乳化及吸附析出的多步骤过程,直接将线性苯乙烯-丁二烯-苯乙烯嵌段共聚物(SBS)包覆到微米级片状FeSiAl合金粒子表面,并研究其电磁性质。结果表明,SBS在片状FeSiAl合金粒子表面形成了均匀致密的包覆层,显著提高了合金粒子的电阻率,其与石蜡2∶1混合样品复介电常数的实部由72降低到30左右。包覆后片状FeSiAl合金粒子的低频磁性能没有受到负面影响,而其高频性能由于阻抗匹配性的提升得到了明显的改善,因而片状FeSiAl@SBS复合粒子具有兼顾低频与宽带的吸波特性。Flaky FeSiAl particles show excellent magnetic properties at low frequency but exhibit large permittivity and impedance mismatch at high frequency.The surface of the flake FeSiAl alloy particles was coated with thin layer of styrene-butadiene-styrene block copolymer(SBS)by a process consisting of dissolving organic polymer,mixing with the FeSiAl particles,emulsifying and then evaporating the solvent.Then the electromagnetic properties of the coated FeSiAl particles were studied.The results show that SBS forms a layer of thin,uniform and dense coating on the surface of the flake FeSiAl alloy particles,which significantly improves the resistivity of the alloy powder.The real part of the complex dielectric constant of the coated alloy particles mixed with paraffin 2∶1 is decreased from 72 to around 30.The low frequency magnetic properties are not adversely affected,and its high-frequency performance is significantly improved due to the improvement of impedance matching.Therefore,the coating of SBS endow a better performance to the flaky FeSiAl alloy particles in broadband microwave absorption.

关 键 词：吸收剂 有机包覆 阻抗匹配 吸波性能 

分 类 号：TB34[一般工业技术—材料科学与工程]