This paper presents an electromagnetic-mechanical repair patch (EMRP) to restore the mechanical and electromagnetic (EM) wave absorption performance of a radar-absorbing structure (RAS) damaged by lightning strike. Several researchers have primarily focused on ensuring high repair efficiency, particularly in terms of the primary load-bearing properties of repaired fiber-reinforced plastics. However, no study has proposed a practical repair approach that considers the multi-functionality of the radar-absorbing structure. The EMRP method can be used to repair lightning strike damage in a radar-absorbing structure with electroless nickel-plated glass fabric, considering the need to maintain structural integrity and electrical continuity to achieve a high repair efficiency. Damage due to an artificial lightning strike was assessed in terms of area and depth of the damage using image processing, ultrasonic C-scan, and micro X-ray inspection. The EM characteristics of one-dimensional return loss scanning and the echo radar-cross-section level were measured to verify the stealth performance of the repaired radar absorber in the X-band. In addition, the tensile test results demonstrated that the repaired radar absorber had a high recovery rate of 93% compared to the pristine radar absorber. The experimental results obtained in this study validate the use of the proposed EMRP method in repairing radar-absorbing structures.
Bibliographical noteFunding Information:
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was supported by a National Research Foundation of Korea (NRF) grant funded by the Ministry of Science and ICT (NRF-2017R1A5A1015311). This work was supported by the Aerospace Low Observable Technology Laboratory Program of the Defense Acquisition Program Administration and the Agency for Defense Development of the Republic of Korea.
© The Author(s) 2020.
All Science Journal Classification (ASJC) codes
- Ceramics and Composites
- Mechanics of Materials
- Mechanical Engineering
- Materials Chemistry