Journal of Materials Science

, Volume 54, Issue 8, pp 6668–6683 | Cite as

Structure–property relationships of aramid fibers via X-ray scattering and atomic force microscopy

  • Michael R. Roenbeck
  • Julia Cline
  • Vincent Wu
  • Mehdi Afshari
  • Steve Kellner
  • Patrick Martin
  • Juan David Londono
  • Laura E. Clinger
  • David Reichert
  • Steven R. Lustig
  • Kenneth E. StrawheckerEmail author


Real-space methods of characterizing high-performance fibers’ inherent morphologies will greatly enhance our understanding of the key structural features within fibers and their impacts on mechanical performance. Here, we report on structure–property correlations of two new classes of commercial DuPont Kevlar fibers, termed “K29 sample test” and “K49 sample test,” as well as conventional K29 and K49 fibers.* Through multifrequency atomic force microscope scans of internal fiber surfaces prepared by a focused ion beam notch technique, we directly capture nano- and microstructural features that define the inherent structures of these fibers. Integrating these findings with X-ray scattering experiments, we relate crystallographic and real-space measurements to each other, highlighting how multiscale structural motifs manifest within fibers. By carrying out tensile tests on single fibers drawn from the same tows, we also glean new insights into the structure–property relationships that dictate the mechanical behavior of these fibers.



Research was sponsored by the Army Research Laboratory and was accomplished under Cooperative Agreement Numbers W911NF-16-2-0008, W911NF-18-2-0273 and W911QX-16-D-0014. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the Army Research Laboratory or the US Government. The US Government is authorized to reproduce and distribute reprints for Government purposes notwithstanding any copyright notation herein. The authors would also like to acknowledge Eric Wetzel, Emil Sandoz-Rosado, and Paul Moy (US Army Research Laboratory) for helpful discussions.

Supplementary material

10853_2018_3282_MOESM1_ESM.docx (1021 kb)
Supplementary material 1 (DOCX 1021 kb)


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Copyright information

© This is a U.S. government work and its text is not subject to copyright protection in the United States; however, its text may be subject to foreign copyright protection  2019

Authors and Affiliations

  • Michael R. Roenbeck
    • 1
  • Julia Cline
    • 1
  • Vincent Wu
    • 1
  • Mehdi Afshari
    • 2
  • Steve Kellner
    • 2
  • Patrick Martin
    • 2
  • Juan David Londono
    • 3
  • Laura E. Clinger
    • 3
  • David Reichert
    • 2
  • Steven R. Lustig
    • 4
  • Kenneth E. Strawhecker
    • 1
    Email author
  1. 1.U.S. Army Research LaboratoryAberdeen Proving GroundUSA
  2. 2.E. I. du Pont de Nemours and Company, DuPont Safety and ConstructionRichmondUSA
  3. 3.E. I. du Pont de Nemours and Company, DuPont Science and InnovationWilmingtonUSA
  4. 4.Department of Chemical EngineeringNortheastern UniversityBostonUSA

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