Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7876975 | Acta Materialia | 2018 | 18 Pages |
Abstract
In this work, we report the magnetic and microwave absorption properties of the Sm1.5Y0.5Fe17-xSix (0.0â¯â¤â¯xâ¯â¤â¯1.5) and their paraffin composites. It was found that the introduction of Si can remarkably tune the intrinsic magnetic properties of the Sm1.5Y0.5Fe17-xSix, making the Sm1.5Y0.5Fe17-xSix-paraffin composites excellent microwave absorption materials. The milled Sm1.5Y0.5Fe17-xSix powders have flake-like shape with length of 5â¯Î¼m and thickness of 100â¯nm, consisting of sphere-like crystalline grains with size of about 11â¯nm. In the tested frequency region, the permeability μⲠof the composites shows, especially at higher frequency, little decrease after introducing the Si, while the permittivity εⲠdecreases by about 40% with Si content increasing from xâ¯=â¯0.0 to xâ¯=â¯1.5, which is advantageous to improve the impedance match and enhance the performance of the microwave absorption. The peak frequency (fp) of the reflection loss (RL) peak with same composite thickness increases with increasing the Si content, in accordance with the variation of the calculated resonance frequency *frâ¯=â¯f(Ms, Haθ, HaÏ, μi). Moreover, the qualified bandwidth (QB, RLâ¯â¤â¯â10â¯dB) also increases remarkably with increasing the Si content due to a better impedance match. An extraordinary dielectric microwave absorption peak was also found in the composites, which can further increase the QB in some degree. A maximum RL of â55.1â¯dB and a QB of 3.7â¯GHz (12.7-16.4â¯GHz) are obtained for the Sm1.5Y0.5Fe15.5Si1.5-paraffine composite, suppressing many reported microwave absorbing materials.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Wenyun Yang, Yinfeng Zhang, Guanyi Qiao, Youfang Lai, Shunquan Liu, Changsheng Wang, Jingzhi Han, Honglin Du, Yan Zhang, Yingchang Yang, Yanglong Hou, Jinbo Yang,