Composites Research

The Korean Society for Composite Materials (한국복합재료학회)
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Effect of Fiber Orientation on the Mechanical Properties of Long Fiber Reinforced Composites

장섬유강화 복합재료의 섬유 배향특성이 기계적 특성에 미치는 영향

  • Huh, Mongyoung (Composites Engineering Center, Korea Institute of Carbon Convergence Research Institute) ;
  • Lee, Haksung (Design and Analysis Center, Korea Institute of Carbon Convergence Research Institute)
  • Received : 2019.12.12
  • Accepted : 2019.12.17
  • Published : 2019.12.31
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Abstract

Long-fiber-reinforced composites have the advantages of cost-competitiveness and high degree of freedom of molding compared to continuous-fiber-reinforced composites. On the other hand, it is difficult to ensure uniform characteristics due to the randomly distributed fiber orientation incurred from the process of manufacturing intermediate materials. In this study, the effect of the directionality of LFPS (Long Fiber Prepreg Sheet) materials on the mechanical properties was analyzed. The eddy current measurement method was used to analyze fiber orientations, and tensile and compression tests on LFPS materials were performed according to ASTM standards. In addition, the test results and theoretical values of LFPS materials were verified using the ROM (rule-of-mixtures) theory. These results confirmed the effect of fiber orientation on mechanical properties of discontinuous-fiber-reinforced composites.

장섬유강화 복합재료는 연속섬유강화 복합재료 대비 가격 경쟁력 및 성형 자유도가 높은 장점을 가지고 있다. 반면에 중간재를 제조하는 과정에서 무작위로 분산되는 특성으로 균일한 배향성을 확보하는데 어려움이 있다. 이에 본 연구에서는 LFPS(Long Fiber Prepreg Sheet) 소재의 재현성 검증을 위하여, 섬유의 배향 각도를 측정하고 이를 기반으로 기계적 물성치와의 상관관계를 분석하였다. 배향특성 분석을 위하여 와류측정방식을 사용하였으며, ASTM 기준에 준하여 LFPS 소재의 인장 및 압축 시험평가를 수행하였다. 추가적으로, 탄성강성 예측이론인 ROM(Rule of Mixture)을 활용하여 LFPS 소재의 시험결과와 이론치를 검증하였다. 이러한 결과를 통해 비연속섬유강화 복합재료의 섬유 배향특성이 기계적 특성에 미치는 영향을 확인하였다.

Keywords

References

  1. Lee, H., Huh, M., Yoon, J., Lee, D., Kim, S., and Kang, S., "Fabrication of Carbon Fiber SMC Composites with Vinyl Ester Resin and Effect of Carbon Fiber Content on Mechanical Properties," Carbon Letters, Vol. 22, 2017, pp. 101-104. https://doi.org/10.5714/CL.2017.22.101
  2. Kim, D.-H., Kim, H.-G., and Kim, H.-S., "Design Optimization and Manufacture of Hybrid Glass/carbon Fiber Reinforced Composite Bumper Beam for Automobile Vehicle," Composite Structures, Vol. 131, 2015, pp. 742-752. https://doi.org/10.1016/j.compstruct.2015.06.028
  3. Lee, S.-W., and Chang, S.-H., "Design of a Stainless Steel Insert for Mechanical Joining of Long Fiber-reinforced Composite Structures," Composites Research, Vol. 31, No. 4, 2018, pp. 139-144.
  4. Kim, S.J., Park, S.W., and Kim, T.U., "Study for Determining Design Allowable Values of Light Weight Composite Unmanned Aircraft Structures," Journal of Aerospace System Engineering, Vol. 11, No. 4, 2017, pp. 1-7. https://doi.org/10.20910/JASE.2017.11.4.1
  5. Schmidt, C., Schultz, C., Weber, P., and Denkena, B., "Evaluation of Eddy Current Testing for Quality Assurance and Process Monitoring of Automated Fiber Placement," Composites Part B: Engineering, Vol. 56, 2014, pp. 109-116. https://doi.org/10.1016/j.compositesb.2013.08.061
  6. Lee, H., Choi, C.-W., Jin, J.-W., Huh, M., Lee, S., and Kang, K.-W., "Homogenization-based Multiscale Analysis for Equivalent Mechanical Properties of Nonwoven Carbon-fiber Fabric Composites," Journal of Mechanical Science and Technology, Vol. 33, No. 10, 2019, pp. 4761-4770. https://doi.org/10.1007/s12206-019-0917-6
  7. Richardson, D., "The Fundamental Principles of Composite Material Stiffness Predictions," University of the West of England, Presentation, 2012.
  8. Lee, S.-P., Jin, J.-W., and Kang, K.-W., "Probabilistic Analysis for Mechanical Properties of Glass/epoxy Composites Using Homogenization Method and Monte Carlo Simulation," Renewable Energy, Vol. 65, 2014, pp. 219-226. https://doi.org/10.1016/j.renene.2013.09.012
  9. Lee, J.E., Kang, D.S., Lee, B.H., Baek, J.H., Kim, J.G., and Hwang, K.M., "A Study on Elastic Modulus Predictions and Dynamic Characteristics Analysis of Composite Structures using CFRP (HPW193/RS1222)," Journal of the Korean Society for Precision Engineering, Vol. 33, No. 10, 2016, pp. 821-828. https://doi.org/10.7736/KSPE.2016.33.10.828