| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain amorphous alloy particles high in electrical resistance and provide an electromagnetic wave absorber that prevents the reflection and transmission of electromagnetic wave in a magahertz range by using the particles. <P>SOLUTION: The high resistivity amorphous metal particles are composed of flakes which are 50 to 500 μm in diameters and 1 to 50 μm in thicknesses, contain 40 to 90 at.% Fe or 50 to 90 at.% Co, and are covered with 10 to 1000 A thick silane oligomer layer. This silane oligomer layer is formed by immersing the flakes in a solution obtained by hydrolyzing a water soluble silane coupling agent at 50°C or higher, filtering them, and heating them at 200 to 300°C for one hour or longer in a vacuum level of 10<SP>-4</SP>Torr. or lower, under the condition that the ratio of the weight of the solution and the surface area of the amorphous alloy flakes is 1 to 100 g/m<SP>2</SP>, and repeating these processes 2 to 10 times. The electromagnetic wave absorber is made of a composite material obtained by dispersing the high resistivity amorphous particles into resin at a rate of 30 to 70 volume percent. <P>COPYRIGHT: (C)2003,JPO |
