稀土氧化物对Ni-Zn铁氧体/泡沫铝吸波性能的影响

Effect of Doping Rare-Earth Oxide on Microwave Absorbing Properties of Ni-Zn Ferrite/Al-Alloy Foams

为研究掺杂稀土氧化物对Ni-Zn铁氧体/泡沫铝材料吸波性能,在泡沫铝表面涂覆了单一Ni-Zn铁氧体(记作CFe)和掺杂质量分数为1%的稀土氧化物的Ni-Zn铁氧体复合粉(记作CFe′),利用GJB2038-94"雷达吸波材料反射率测试方法"中的雷达截面(RCS)法对材料微波反射率进行了测量,扫描电镜(SEM)和X射线衍射仪(XRD)对吸波剂的形貌和物相进行了分析。结果表明,在12～18GHz频段内,泡沫铝表面涂敷单一的铁氧体其吸收量为1.8dB,加入稀土氧化物后,其吸波值由1.8dB增至2.65dB,在26.5～40GHz频段内时,添加稀土氧化物后,吸收量有较大的提高,从11dB增加到15dB,10dB带宽扩展近6倍。因此掺杂稀土氧化物是提高吸波材料性能的一种途径。

To study the effect of doping the rare-earth oxide on the microwave absorbing property of Ni-Zn ferrite/Al-alloy foams, the surface of Al-alloy foams were coated with Ni-Zn ferrite （denoted by CFe）, and doping 1% （mass percent） of rare-earth oxide of Ni- Zn ferrite（denoted by CFe＇） respectively. The coated Al-alloy foams were tested according to the standard GJB 2038-94 ＂Method to test the reflectivity of radar absorbing materials＂, i. e. , the RCS （radar crosssection） method. The morphology and distribution of microwave absorbent were analyzed by scanning elec-tron microscopy（SEM） and X-ray diffraction（XRD）. The results indicated that in the 12 - 18 GHz band the microwave absorbability of Al-alloy foams materials coated with Ni-Zn ferrite reached 1.8 dB, and when doped the rare-earth oxide, the absorbing properties were increased from 1.8 dB to 2.65 dB. In the 26.5 -40 GHz band, the absorbing properties were greatly increased from lldB to 15 dB and 10 dB bandwidth was sixfold increase approximately. So doping the rare-earth oxide could improve absorbing property of absorption materials.