A cobalt-coated reticulated porous alumina for radar-absorption applications

  • Jang-Hoon HaEmail author
  • Sujin Lee
  • Jae Ryung Choi
  • Jongman Lee
  • In-Hyuck Song
  • Tai-Joo Chung


Recently, porous ceramics have received much attention because of their excellent chemical and thermal stabilities, despite their mechanical instability. Among the various types of porous ceramics, reticulated porous ceramics (RPCs) have been newly fabricated. However, there is still insufficient data on the characteristics of RPCs for radar-absorption applications. Therefore, in this study, the feasibility of using RPCs of alumina (reticulated porous alumina, RPA) is investigated. It is examined whether RPA can achieve appropriate mechanical strength, be coated by a radar-absorbing material (RAM), and have radar-absorbing properties. The compressive strength of the RPA specimens is significantly enhanced from 0.07 to 1.03 MPa by the combined effect of increasing the number of alumina coating, sintering temperature, and pore density. The measured reflection loss is less than − 3 dB over the X-band range (8.2–12.4 GHz) for an 8.46-mm-thick RPA specimen coated with 40 wt.% cobalt slurry, which corresponds to 49.9% absorption. However, the calculated reflection loss of an RPA specimen with a thickness of 38.27 mm and coated with 40 wt.% cobalt slurry approaches − 15 dB at 10.0 GHz, corresponding to a 96.8% absorption of the radar wave.


Reticulated porous ceramics Alumina Cobalt Radar-absorption properties 


Funding information

This study was supported financially by Fundamental Research Program of the Korean Institute of Materials Science (KIMS). This work was supported by the Fundamental Research Program of the Korea Institute of Materials Science (KIMS) (Grant No. PNK5930).


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Copyright information

© Australian Ceramic Society 2019

Authors and Affiliations

  1. 1.Powder and Ceramics DivisionKorea Institute of Materials ScienceChangwonRepublic of Korea
  2. 2.School of Materials Science and Engineering, Industrial Technology Center for Environment-friendly MaterialsAndong National UniversityAndongRepublic of Korea

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