A Theory of Commercial Yarn Testing

• Published in: Textile research journal 1948-06, Vol.18 (6), p.338-350
• Main Authors: Geyer, Charles J., Reichardt, C.H., Halsey, George
• Format: Article
• Language: English
• Subjects: Constants; Mathematical models; Shear; Spring constant; Springs; Textiles; Viscoelasticity; Yarns
• ISSN: 0040-5175; 1746-7748
• DOI: 10.1177/004051754801800602

A method has been devised for the application of the theory of the three-element shear model of Eyring and coworkers to textiles which does not necessitate the location of the "basic spring line" and thus is readily applicable to both yarn and fiber tests and to the commercial inclined-plane and pendulum-type testers. It is also applicable as a first approximation to those textiles which do not possess a "basic spring line" as such. The method employs the conven tional spring constants or elastic moduli but determination of the viscous constants involves the magnitude of the relaxation in constant-rate-of-elangation experiments (or the magnitude of the creep in constant-rate-of-loading experiments) from the upper envelope per interval of time. The relationship has been employed to establish the correlation between the viscoelastic prop erties of "slashed" and "unslashed" viscose tire-cord rayon yarns and also to show the identity of single-filament stress-strain relationships with those of yarns of normal twist of the same textile. The simplicity of technique which enables this method to be used as a routine labora tory test for the determination of the viscoelastic properties of textiles is an advantage over previous methods, which were often unsatisfactory from both a theoretical and an experimental viewpoint.