| 摘要 |
An absorber includes a plurality of shredded foam particles and a plurality of fiber whiskers. The fiber whiskers are interspersed among, and attach to the shredded foam particles to create a foam-fiber mixture. A curable adhesive is added to the foam-fiber mixture and the cured mixture is molded to form the radar absorber. The fiber whiskers are less than about two weight percent of the absorbers. The foam particles are preferably formed by shredding scrap foam. The particles are generally irregularly shaped and the size of the particles can be expressed as having a mean size of about +E,fra 1/8+EE '' to 1'' diameter, although the particles are not necessarily spherical. The fibers are about +E,fra 1/8+EE '' to +E,fra 3/4+EE '' in length and have a diameter of about 7.3 microns. To form the absorber, shredded foam particles are mixed with fiber whiskers, and the fiber whiskers attach themselves to the surface of the shredded foam particles. The mixing is preferably driven by turbulent air which causes the fiber whiskers to attach to the shredded foam. The velocity of the air is then reduced and the tumbling foam-fiber mixture is sprayed with curable polyurethane binder. The resultant mass then placed into a mold and cured to form the absorber. Advantageously, the absorber of the present invention is significantly less expensive than prior art absorbers. This is primarily due to the use of shredded scrap foam and the reduced need for fire retardant materials. In addition, the cured foam-fiber mixture is easily molded to create the desired absorber shape. Molding allows various absorber shapes to be formed.
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