Image Characterization to Quantify the Surface Roughness of the Damaged High Performance Polymer Fibers

Graduate #106
Discipline: Technology and Engineering
Subcategory: Materials Science

Pavan Akunuri - Virginia State University
Co-Author(s): Krishan Agrawal and Steven T. Correale, Virginia State University, VA

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This study describes the development of a method to quantify the surface roughness of the fibers and correlate it with the reduction in tension strength in ropes. Ingression of particulate materials in synthetic ropes is a concern due to damage they can inflict to the constituent fibers resulting in the reduction of the tensile strength in these ropes. During normal operations a rope is cycled through varying tensions as loads are added or removed. The cycling of tension results in the displacement of fibers between themselves and with any particulate matter which may be present. The subsequent movement of the particles against the surface of the fibers abrades the fibers which reduces their cross sectional area and will eventually severe some of them resulting in a loss of the rope’s tension strength. The abraded surface can be characterized in terms of roughness, which is characterizes as a high frequency component on a surface.

Braided ropes samples infused with fine particles were cycled through varying loads using an Instron. The breaking strengths of abraded ropes were then measured using the Instron. A Hitachi S-4500 cold field emission scanning electron microscope (SEM) was used to examine the damage to the surface of the fibers. The imaging of the surface damage to the fiber was facilitated by using secondary electrons along with a low excitation voltage. Using the image analysis capability in MATLAB a technique was developed to quantify the surface roughness from electron micrographs of the abraded fibers. The correlation between the roughness as measured using this technique and the tension test results showed the benefit and potential of using these techniques for studying abrasion in synthetic ropes.

Not Submitted

Funder Acknowledgement(s): This study was funded by Honeywell Specialty Products Division Colonial Heights VA 23834.

Faculty Advisor: Krishan Agrawal, kagrawal@vsu.edu