DOI QR코드

DOI QR Code

Cure Monitoring of Epoxy Resin by Using Fiber Bragg Grating Sensor

광섬유 브래그 격자 센서를 이용한 에폭시 수지의 경화도 모니터링

  • Lee, Jin-Hyuk ;
  • Kim, Dae-Hyun (Department of Mechanical and Automotive Engineering, Seoul National University of Science and Technology)
  • 이진혁 (한국전력공사 전력연구원) ;
  • 김대현 (서울과학기술대학교 기계.자동차공학과)
  • Received : 2016.04.06
  • Accepted : 2016.06.16
  • Published : 2016.06.30

Abstract

In several industrial fields, epoxy resin is widely used as an adhesive for co-curing and manufacturing various structures. Controlling the manufacturing process is required for ensuring robust bonding performance and the stability of the structures. A fiber optic sensor is suitable for the cure monitoring of epoxy resin owing to the thready shape of the sensor. In this paper, a fiber Bragg grating (FBG) sensor was applied for the cure monitoring of epoxy resin. Based on the experimental results, it was demonstrated that the FBG sensor can monitor the status of epoxy resin curing by measuring the strain caused by volume shrinkage and considering the compensation of temperature. In addition, two types of epoxy resin were used for the cure-monitoring; moreover, when compared to each other, it was found that the two types of epoxy had different cure-processes in terms of the change of strain during the curing. Therefore, the study proved that the FBG sensor is very profitable for the cure-monitoring of epoxy resin.

에폭시 수지는 여러 산업분야에서 다양한 구조물의 접합과 제조에 사용된다. 구조물의 안전성과 접합재료의 최적 성능 확보를 위해서는 에폭시 수지의 경화 과정 모니터링 기반의 공정 제어가 요구된다. 광섬유 센서는 실과 같은 형태적 특징으로 인해 에폭시 수지의 경화 모니터링에 적합한 센서이다. 본 연구에서는 광섬유 브래그 격자 센서(fiber Bragg grating, FBG)를 이용하여 에폭시 수지의 경화 모니터링 연구를 수행하였다. 실제 실험을 통해, FBG를 기반으로 에폭시 수지의 경화과정에서 에폭시의 부피 수축에 의해 센서에 가해지는 변형률을 측정하고 온도의 변화에 의한 신호 변화를 보정하여 경화과정에서 발생하는 변형률의 정확한 모니터링이 가능함을 확인하였다. 추가적으로, 두 가지 에폭시 수지의 경화도 과정을 비교 분석하여 에폭시 종류에 따른 경화과정의 차이를 확인하였다. 결론적으로 FBG 센서가 에폭시 수지의 경화도 모니터링에 유용하다는 점을 확인하였다.

Keywords

References

  1. R. F. Gibson, "Principles of Composite Material Mechanics," 3rd Ed., CRC Press, USA, pp. 1-52 (2011)
  2. D. Huston, W. McDonough, B. Fanconi, F. Mopsik, F. Wang, F. Phelan and M. Chiang, "Assessment of the state-of-the-art for process monitoring sensors for polymer composites," NISTIR 4514, U.S. Department of Commerce NIST, USA, pp. 24-28 (1991)
  3. R. J. Boucher, "History of solar flight," AIAA paper, pp. 84-1429 (1984)
  4. J.-C. Kim, Y.-S. Lee, J.-H. Lee, I.-H. Choi, D.-H. Kim and S.-K. Cheong, "A study on the solar cell lay-down for solar powered aircraft using secondary-bondiong method," Proceedings of the KSME 2010 Fall Annual Meeting, pp. 399-403 (2010)
  5. J. B. Kim, J. H. Byun, C. H. Lee, S. K. Lee and M. K. Um, "Study on cure monitoring for epoxy resin using fiber optic sensor system," Proceedings of the KSCM 2005 Spring Conference, pp. 37-41 (2005)
  6. V. M. Murukeshan, P. Y. Chan, L. S. Ong and L. K. Seah, "Cure monitoring of smart composites using fiber Bragg grating based embedded sensors," Sensors and Actuators A: Physical, Vol. 79, No. 2, pp. 153-161 (2000) https://doi.org/10.1016/S0924-4247(99)00266-6
  7. F. Colpo, L. Humbert, P. Giaccari and J. Botsis, "Characterization of residual strains in an epoxy block using an embedded FBG sensor and the OLCR technique," Composites: Part A, Vol. 37, No. 34, pp. 652-661 (2006) https://doi.org/10.1016/j.compositesa.2005.05.009
  8. J. Im, M. Kim, K.-S. Choi, T.-K. Hwang and I.-B. Kwon, "FBG sensor probes with silver epoxy for tracing the maximum strain of structures," Journal of Korean Society for Nondestructive Testing, Vol. 33, No. 5, pp. 459-464 (2013) https://doi.org/10.7779/JKSNT.2013.33.5.459
  9. D. H. Kim, K. H. Lee, B. J. Ahn, J. H. Lee, S. K. Cheong and I. H. Choi, "Strain and damage monitoring in solar-powered aircraft composite wing using fiber Bragg grating sensors," SPIE Smart Structures and Materials+ Nondestructive Evaluation and Health Monitoring, p. 869222 (2013)
  10. H. Y. Kim, D. Kang, J. H. Lee and D. H. Kim, "Characteristics of thermal coefficient of fiber Bragg grating for temperature measurement," Transactions of the KSME A, Vol. 37, No. 8, pp. 999-1005 (2013) https://doi.org/10.3795/KSME-A.2013.37.8.999
  11. K. F. Schoch, Jr., P. A. Panackal and P. P. Frank, "Real-time measurement of resin shrinkage during cure," Thermochimica Acta, Vol. 417, No. 1 pp. 115-118 (2004) https://doi.org/10.1016/j.tca.2003.12.027