稀土对铁砂基电波吸收材料特性的影响

The Influence of Rare Earth on Properties of Iron Sand Based Radar Absorption Materials

铁砂基电波吸收材料在７～１２ＧＨｚ频段有两个吸收峰，加入稀土材料后，第一吸收峰移向低频，第二吸收峰位置不变；吸收量Ａ由１１．２ｄＢ增至１４．５ｄＢ；匹配厚度由１．２５ｍｍ减至１．２０ｍｍ。同时添加稀土和介电材料（或六角铁氧体）使吸收量有较大的提高，最大可达２７ｄＢ，匹配厚度亦增至１．６ｍｍ，发现稀土添加量存在极值问题。因稀土添加量少，仍是一种廉价的吸收材料。

Iron sand based radar absorption material has two absorption peaks between 7 GHz and 12GHz. When adding rare earth to it, the position of the first absorption peak moves to low frequency, the position of the second absorption peak is not changed; the absorptivity is increased from 11.2dB to 14.5dB; matching thickness is reduced from 1.25mm to 1.20 mm. When adding rare earth and dielectric material (or hexagonal ferrite)to it simultaneously, the absorptivity is greatly increased, the maximum can reach 27dB, matching thickness is also increased to 1.61 mm. We can find that there is a maximum amount of the adding of rare earth. This kind of radar absorption material is still very cheap because the amount of rare earth added is quite small.