Fabrication of Light Weighted Microwave Absorbers Using Silver-Coated Hollow Microspheres

은도금 중공미세구를 이용한 경량 전파흡수체의 제조

  • 김욱중 (충북대학교 공과대학 재료공학과, 컴퓨터 정보통신 연구소) ;
  • 김선태 (충북대학교 공과대학 재료공학과, 컴퓨터 정보통신 연구소) ;
  • 김성수 (충북대학교 공과대학 재료공학과, 컴퓨터 정보통신 연구소) ;
  • 권순길 (국방과학연구소 기술연구본부 5부) ;
  • 안준모 (국방과학연구소 기술연구본부 5부) ;
  • 김근홍 (국방과학연구소 기술연구본부 5부) ;
  • 천창환 (국방과학연구소 기술연구본부 5부)
  • Published : 2001.11.01

Abstract

Conductive microspheres with a density of 0.2 g/cc were fabricated by electroless silver plating for application to the light-weighted microwave absorbers. The silver plating was conducted with the variation of plating conditions (sensitizing condition, $AgNO_3$, concentration, amount of reducing agent). Specimens have very low electro-resistivity. Under an optimum processing condition, conductive microspheres with uniform silver plating layer can be produced. Rubber-sphere composites were fabricated and their microwave absorbing properties were measured by HP8722D Network Analyzer. It was found that the lower the electrical resistance of microsphere, the better the microwave absorbing properties. Feasibility of microwave absorbers using this microspheres can be demonstrated with the result of microwave reflection loss of -15 dB and thickness of 1.44 mm.

Keywords

References

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