Article Article
Ultrasonic Evaluation of Porosity in Out-of-Autoclave Carbon Fiber–Reinforced Polymer Composite Material

Ultrasonic longitudinal wave propagation is studied in out-of-autoclave (OoA) carbon fiber–reinforced polymer composite material with varying levels of porosity contents. A combination of cure pressures and a solvent is used to produce specimens with void contents in the range of 0% to 22%. Ultrasonic measurements are made in through-transmission mode, and the data is processed to study various aspects of wave interaction with porosity in OoA specimens. The specimens with a wide range of void contents have enabled the study of broader trends of ultrasonic center frequency, wave velocity, and attenuation with respect to porosity. Results show ultrasonic center frequency and wave velocity are decreased linearly as the void content increases. The relationship of ultrasonic wave attenuation can be approximated by a logarithmic relationship when considering the full range of void content studied. Strength measurements of specimens with varying void contents are made using the flatwise tensile (FWT) test. It is observed that the strength rapidly decreases with increasing porosity. Correlations made between FWT strength, ultrasonic wave velocity, and attenuation are best described by logarithmic relationships. The data shows a potential for inferring strength knockdowns due to the presence of porosity based on ultrasonic measurements.

DOI: https://doi.org/10.32548/2021.me-04198

References

Birt, E.A., and R.A. Smith, 2004, “A Review of NDE Methods for Porosity Measurement in Fibre-Reinforced Polymer Composites,” Insight – Non-Destructive Testing and Condition Monitoring, Vol. 46, No. 11, pp. 681–686, https://doi.org/10.1784/insi.46.11.681.52280

Boyd, J., and R.K. Maskell, 2001, “Product Design for Low Cost Manufacturing of Composites for Aerospace Applications,” Proceedings of SAMPE 2001: A Materials and Processes Odyssey, 6–10 May, Long Beach, CA, pp. 898–907

Centea, T., L.K. Grunenfelder, and S.R. Nutt, 2015, “A Review of Out-of-Autoclave Prepregs–Material Properties, Process Phenomena, and Manufacturing Considerations,” Composites Part A: Applied Science and Manufacturing, Vol. 70, pp. 132–54, https://doi.org/10.1016/j.compositesa.2014.09.029

Cobbs, S.D., and G.G. Bond, 2012, “Development of Porosity Standards for CYCOM 5320-1 Out-of-Autoclave Composite Laminates,” Proceedings of SAMPE 2012, 21–24 May, Baltimore, MD

Gardener, G., 2011, “Out-of-Autoclave Prepregs: Hype or Revolution?” Composites World, 1 January, https://www.compositesworld.com/articles/out-of-autoclave-prepregs-hype-or-revolution

Grunenfelder, L.K., and S.R. Nutt, 2010, “Void Formation in Composite Prepregs–Effect of Dissolved Moisture,” Composites Science and Technology, Vol. 70, No. 16, pp. 2304–2309, https://doi.org/10.1016/j.compscitech.2010.09.009

Ishii, Y., S. Biwa, and A. Kuraishi, 2016, “Influence of Porosity on Ultrasonic Wave Velocity, Attenuation and Interlaminar Interface Echoes in Composite Laminates: Finite Element Simulations and Measurements,” Composite Structures, Vol. 152, pp. 645–653, https://doi.org/10.1016/j.compstruct.2016.05.054

Jeong, H., 1997, “Effects of Voids on the Mechanical Strength and Ultrasonic Attenuation of Laminated Composites,” Journal of Composite Materials, Vol. 31, No. 3, pp. 276–292, https://doi.org/10.1177%2F002199839 703100303

Jeong, H., and D.K. Hsu, 1995, “Experimental Analysis of Porosity-Induced Ultrasonic Attenuation and Velocity Change in Carbon Composites,” Ultrasonics, Vol. 33, No. 3, pp. 195–203, https://doi.org/10.1016 /0041-624X(95)00023-V

Martin, B.G., 1976, “Ultrasonic Attenuation Due to Voids in Fibre-Reinforced Plastics,” NDT International, Vol. 9, No. 5, pp. 242–246, https://doi.org/10.1016/0308-9126(76)90004-3

Martin, B.G., 1977, “Ultrasonic Wave Propagation in Fiber‐Reinforced Solids Containing Voids,” Journal of Applied Physics, Vol. 48, No. 8, pp. 3368–3373, https://doi.org/10.1063/1.324176

Mehdikhani, M., L. Gorbatikh, I. Verpoest, and S.V. Lomov, 2019, “Voids in Fiber-Reinforced Polymer Composites: A Review on Their Formation, Characteristics, and Effects on Mechanical Performance,” Journal of Composite Materials, Vol. 53, No. 12, pp. 1579–669, https://doi.org/10.1177%2F0021998318772152

Mouritz, A.P., 2000, “Ultrasonic and Interlaminar Properties of Highly Porous Composites,” Journal of Composite Materials, Vol. 34, No. 3, pp. 218–39, https://doi.org/10.1177/002199830003400303

Papadakis, E.P., 1965, “Ultrasonic Attenuation Caused by Scattering in Polycrystalline Metals,” Journal of the Acoustical Society of America, Vol. 37, pp. 711–717, https://doi.org/10.1121/1.1909401

Reynolds, W.N., and S.J. Wilkinson, 1978, “The Analysis of Fibre- Reinforced Porous Composite Materials by the Measurement of Ultrasonic Wave Velocities,” Ultrasonics, Vol. 16, No. 4, pp. 159–163, https://doi.org/10.1016/0041-624X(78)90071-9

Smith, R.L., W.N. Reynolds, and H.N.G. Wadley, 1981, “Ultrasonic Attenuation and Microstructure in Low-Carbon Steels,” Metal Science, Vol. 15, No. 11–12, pp. 554–558, https://doi.org/10.1179/msc.1981.15.11-12.554

Stone, D.E., and B. Clarke, 1975, “Ultrasonic Attenuation as a Measure of Void Content in Carbon-Fibre Reinforced Plastics,” Non-destructive Testing, Vol. 8, No. 3, pp. 137–45, https://doi.org/10.1016/0029-1021(75)90023-7

 

Metrics
Usage Shares
Total Views
252 Page Views
Total Shares
0 Tweets
252
0 PDF Downloads
0
0 Facebook Shares
Total Usage
252