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Deposition of Protective Layer on Stealth Sheet and Evaluation of the Protected Sheet's Mechanical Performance

스텔스 소자의 보호층 도포 및 기계적 성능 평가 연구

  • Sang Yeon So (Optical Stealth Materials Laboratory, Department of Mechanical Engineering, Yonsei University) ;
  • Jae Won Hahn (Optical Stealth Materials Laboratory, Department of Mechanical Engineering, Yonsei University)
  • 소상연 (연세대학교 기계공학과 광학 스텔스 소재 연구실) ;
  • 한재원 (연세대학교 기계공학과 광학 스텔스 소재 연구실)
  • Received : 2023.06.15
  • Accepted : 2023.09.26
  • Published : 2023.10.25

Abstract

We report the results of evaluating the hardness, flexibility, and adhesion between the protective layer and the stealth sheet after applying a protective layer to improve the practicality of the flexible stealth sheet. The result of the ISO 15184 pencil hardness test showed that the hardness increased from HB to 3H by three grades when a protective layer was applied. The flexibility evaluation was conducted by bending the material against cylinders of certain diameters and observing whether cracks occurred according to the ASTM D522 test method. The result showed that the minimum diameter was 0.125 inches. The adhesion was evaluated by using the ASTM D3359 test method, attaching and peeling off an adhesive strip to the protective layer and determining the proportion of the protective layer peeling off. The result was 5B, which is better than the military adhesion limit of 4B.

유연 스텔스 소재의 실용성 향상을 위해 보호층을 입힌 뒤의 경도, 유연성, 보호층과 스텔스 소재의 접착력을 평가하였다. 우선 ISO 15184 연필 시험법을 통해 경도를 측정하였으며, 보호층을 입히기 전과 비교하여 경도가 HB에서 3H로 3등급 올라가는 것을 확인할 수 있었다. 유연성은 ASTM D522 시험법에 따라 소재를 특정 직경의 원기둥에 대고 구부린 뒤 균열 생성 여부를 확인하며 평가하였고, 그 결과 균열이 생성되지 않는 최소 직경이 0.125인치임을 확인하였다. 접착력은 ASTM D3359 시험법에 따라 접착 띠를 보호층에 붙였다 떼어내면서 보호층이 박리되는 비율로 평가하였다. 이를 통해 보호층을 입혔을 시 군용 접착력 한계 조건인 4B보다 높은 결과(5B)를 얻었다.

Keywords

Acknowledgement

과학기술정보통신부 씨앗과제 프로젝트(2022-JB-RD-0106-01-101).

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