24—the Bending Stress-Strain Properties of Single Fibres and the Effect of Temperature and Relative Humidity

An investigation is described in which bending stress–strain curves of several keratin and synthetic fibres were obtained up to bending strains as high as 20%. These results suggest that low-stress compressive yielding is occurring at the intrados of the synthetic fibres during bending. The keratin fibres, on the other hand, do not appear to yield in compression, if at all, until much higher stresses are reached. The variations in nominal bending moduli of wool, nylon, and Terylene fibres with changes in temperature and relative humidity were also investigated.