退火对Fe/Al_2O_3纳米复合物微波吸收性能的影响  

Effect of Annealing on Microwave-absorption Properties of Fe/Al_2O_3 Nanocomposite Prepared by Ball-milling

作　　者：徐送宁[1] 赵美星[1] 孙乃坤[1] 杜宝盛 蔡宗岐[1] 杜胜杰 

机构地区：[1]沈阳理工大学理学院,沈阳110159

出　　处：《材料研究学报》2014年第3期227-232,共6页Chinese Journal of Materials Research

基　　金：辽宁省激光与光信息技术重点实验室建设项目辽科发(2011)20号~~

摘　　要：采用球磨法制备Fe/Al2O3纳米复合物,并在氩气保护下退火,研究了退火对Fe/Al2O3纳米复合物的微观结构、磁性和微波吸收性能的影响。结果表明,退火使样品的晶粒尺寸增大,缺陷减少,微观应力得到释放;同时,退火使Al2O3的缺陷发光峰强度明显减弱,398 nm和484 nm处的发光峰发生蓝移。厚度为7.7 mm的球磨样品,其反射损耗在15.5 GHz频率处达到最大值-11.4 dB。退火使样品的介电损耗和磁损耗均增大,电磁波吸收性能明显提高,厚度为6.4 mm时反射损耗在17 GHz频率处达到最大值-35.5 dB。An Fe/Al2O3 nanocomposite was prepared by high energy ball milling method, and which then annealed at 700℃ for 0.5 h in Ar atmosphere. The effect of annealing on the microstructure, magnetism and microwave-absorption properties of Fe/Al2O3 nanocomposite has been investigated. It follows that the annealing resulted in increasing grain size, decreasing lattice defects and releasing the residual microstrain; meanwhile, decreasing the intensity of photoluminescence peaks of Al2O3 significantly, there- with the peaks at 398 nm and 484 nm exhibit a blue shift. An optimal reflection loss of-11.4 dB at 15.5 GHz was measured for a 7.7 mm thick layer of as-milled composite powder mixture with paraffin. However, the annealing treatment could remarkably enhance the dielectric loss, magnetic loss and microwave absorption performance of the composite, leading to an optimal reflection loss of-35.5 dB at 17 GHz for a layer thickness of 6.4 mm for the annealed composite.

关 键 词：复合材料 FE Al2O3 球磨法 微波吸收 退火 

分 类 号：TB333[一般工业技术—材料科学与工程]