Microwave absorber employing acicular magnetic metallic filaments
US5085931A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 3, 1990 |
| Grant date | Feb 4, 1992 |
| Priority date | — |
| Expiry date | Jul 3, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/268
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An electromagnetic radiation absorber is formed by dispersing into a dielectric binder acicular magnetic metallic filaments with an average length of about 10 micron or less, diameters of 0.1 micron or more, and aspect (length/diameter) ratios between 10:1 and 50:1. Preferably the average length is about 5 micron, the aspect ratios are between 10:1 and 25:1, and the dielectric binder is polymeric. The volume fraction of the filaments may be lower than 35% of the total and still provide satisfactory absorption. An absorbing paint is formed by dissolving the absorber in a base liquid. The absorber or absorbing paint may be applied to a conductive surface, such as a metallic wire, plate or foil. Impedance matching materials are preferred but not required.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.