Wave-absorbing agent and preparation method thereof

[0020] The preparation method of the wave absorber provided by the present invention includes the following steps:

[0021] First, the carbonyl iron powder, C 1 -C 4 After the alcohol solution is uniformly mixed, ball milling is performed to obtain a slurry. In the above steps, according to the mass parts, 200-600 parts of carbonyl iron powder and 630-790 parts of C 1 -C 4 The alcohol solution is mixed uniformly, and then put into the ball mill tank for wet milling. It is ball milled in a horizontal planetary ball mill. The speed of the ball mill is 300-450r/min. The milling time is 12-18h. In the horizontal planetary ball mill, the zirconium used The beads are composed of large and medium zirconium beads with diameters of 10mm and 6mm respectively. The mass ratio of the large and medium zirconium beads is 5-20: 80-95, and the total weight of the large and medium zirconium beads is 2 3Kg, the mass ratio of zirconium beads to carbonyl iron powder is 40-100:1, and the carbonyl iron powder after ball milling has a sheet-like structure with a thickness of 0.5-1.5 μm. In this step, C 1 -C 4 The alcohol solution is selected from one or more combinations of methanol, ethanol, ethylene glycol, propanol, isopropanol, and n-butanol.

[0022] Then, the slurry is heated and dried to obtain a wave absorbing agent. In this step, the above slurry is heated and dried at a temperature of 40-80°C for 5-8 hours to obtain a wave absorbing agent. The thickness of the carbonyl iron powder in the final wave absorbing agent is about 0.5-1.5 μm .

[0023] In the present invention, the carbonyl iron powder is ball-milled to change the morphology from spherical particles to a sheet-like structure with a certain width-to-thickness ratio, realize anisotropic characteristics, suppress eddy current effects, and improve magnetic permeability, thereby improving wave absorption performance and making it It has good performance at low frequencies.

[0024] Example 1

[0025] According to mass parts, mix 200 parts of carbonyl iron powder and 630 parts of ethanol solution evenly, and then put them into a ball mill tank for wet milling, ball milling in a horizontal planetary ball mill, the speed of the ball mill is 300r/min, and the milling time is 12h to obtain Slurry. In the horizontal planetary ball mill, the zirconium beads used are composed of large and medium zirconium beads with diameters of 10mm and 6mm respectively. According to the mass parts, the mass parts of the zirconium beads are 8000 parts, of which, the large and medium zirconium beads The mass ratio of the seed zirconium beads is 5:80.

[0026] The above-mentioned slurry is heated and dried at a temperature of 80° C. for 5 hours to obtain a wave absorber, wherein the thickness of the carbonyl iron powder in the finally obtained wave absorber is about 0.5 μm.

[0027] Example 2

[0028] According to mass parts, 600 parts of carbonyl iron powder and 790 parts of methanol solution are mixed uniformly, and then put into a ball mill tank for wet milling. The ball mill is ball milled in a horizontal planetary ball mill. The speed of the ball mill is 450r/min. The milling time is 18h. In the horizontal planetary ball mill, the zirconium beads used are composed of large and medium zirconium beads with diameters of 10mm and 6mm respectively. According to the mass parts, the mass parts of the zirconium beads are 60000 parts, of which there are large and medium zirconium beads. The mass ratio of zirconium beads is 20:95.

[0029] The above-mentioned slurry is heated and dried at a temperature of 40° C. for 8 hours to obtain a wave absorber, wherein the thickness of the carbonyl iron powder in the finally obtained wave absorber is about 1 μm.