Elastic Properties of Twisted Yarn Biocomposites

Edited by Sabu Thomas, Kuruvilla Joseph, S. K. Malhotra, Koichi Goda and M. S. Sreekala. 

Sh is an elongation along the longitudinal direction. Since the fiber length I and its elongation SI are given as h/cos 9 and Sh x cos 0, respectively, the fiber strain gf is gf = 5 l/l = Shcos 0/h. Thus, the yarn strain is as follows  

This equation is often called a power cosine mle. Thus, the yam modulus following this model is strongly dependent on the elastic modulus of fibers. 

In the above cosine mle, as is obviously seen, the lateral deformation perpendicular to the yarn axis is not taken into consideration. In order to extend the power 

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Elastic Properties of Twisted Yarn Biocomposites 339 Table 10.1 Tensile properties of unidirectional composites with various yarn twist angles. 

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