Large-scale manufacturing of helical auxetic yarns using a novel semi-coextrusion process
Textile Research Journal
(c) The Author(s) 2017
This paper introduces a novel extrusion process for manufacturing helical auxetic yarn (HAY). A range of semi-coextruded HAYs have been manufactured in a cost-effective, consistent and readily usable form. The semi-coextruded HAYs were compared to the conventional spun yarns in terms of tensile properties and auxetic behavior. The results show the presence of the auxetic effect in newly fabricated semi-coextruded HAYs. Similar to the traditional spun HAYs, the new HAYs are sensitive to parameters such as the initial wrap angle, the core/wrap diameter ratio and component moduli. Importantly, a few new manufacturing parameters have been identified for tailoring the auxetic behavior of the semi-coextruded HAYs. The semi-coextruded HAYs are auxetic when an instantaneous true Poisson’s ratio analysis method is applied. The semi-coextruded HAYs give a larger maximum negative Poisson’s ratio than the conventional HAYs due to the advantages of the pre-formed helical wrap structure.
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work is supported by the UK Engineering and Physical Sciences Research Council (EPSRC Grant No. EP/J004553/1).
This is the author accepted manuscript. The final version is available from SAGE Publications via the DOI in this record.
First Published August 17, 2017, pp. 1 - 12