Next Article in Journal
Deterioration of Wood Plastics Composites by the White-Rot Fungus Pycnoporus sanguineus
Previous Article in Journal
On the Representativeness of the Cohesive Zone Model in the Simulation of the Delamination Problem
Article Menu

Export Article

Open AccessArticle

Measuring Fiber Orientation of Elliptical Fibers from Optical Microscopy

Composites Manufacturing and Simulation Center, Purdue University, West Lafayette, Indiana, IN 47906, USA
*
Author to whom correspondence should be addressed.
J. Compos. Sci. 2019, 3(1), 23; https://doi.org/10.3390/jcs3010023
Received: 13 February 2019 / Revised: 22 February 2019 / Accepted: 26 February 2019 / Published: 2 March 2019
  |  
PDF [3372 KB, uploaded 6 March 2019]
  |  

Abstract

The orientation of fibers with elliptical cross-sections cannot be estimated using standard optical microscopy analysis methods in which the ratio of the minor-axis to the major-axis and orientation of the major-axis are directly used to determine the fiber spherical coordinates, θ and ϕ . A new method for estimating the orientation of fibers with elliptical cross-sections is presented and validated using both simulations and experiments. Fibers with elliptical cross-sections rather than circular possess a roll degree of freedom, which significantly affects the dimensions of projected cross-sections in viewing planes. The equations of the projected ellipse of an elliptic cylinder onto a viewing plane are determined in terms of typical spherical coordinate system angles, θ and ϕ , the roll angle, α , and the fiber semi-major and semi-minor diameters. Fiber angles are determined by numerical fitting of the developed equations to measured ellipses. An ambiguity in the determined angles is identified, and, in the special case of fiber bundles, a scheme is presented by which the ambiguity can be resolved. Validation experiments showed that the method is quite effective at estimating fiber orientation from micrographs when fiber cross-section dimensions are measured beforehand, and the additional ambiguity is resolved easily in the case of fiber bundles. View Full-Text
Keywords: fiber orientation; optical microscopy; optical techniques fiber orientation; optical microscopy; optical techniques
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Sharp, N.D.; Goodsell, J.E.; Favaloro, A.J. Measuring Fiber Orientation of Elliptical Fibers from Optical Microscopy. J. Compos. Sci. 2019, 3, 23.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
J. Compos. Sci. EISSN 2504-477X Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top