Biaxial rotation fatigue in textile fibres

Textile fibres used in clothes are very likely to suffer some form of bending and twisting. Also the fibres are more likely to suffer fatigue rather than steady tensile failures. Hence it is essential that bending fatigue techniques are investigated. Biaxial rotation is one of these techniques. In this chapter, types of fibres affected, methods of testing biaxial fatigue and factors affecting biaxial fatigue are investigated. The procedure of fracture is usually by axial splitting indicating the significant strength of the fibre along its axis due to its long aligned molecules. The axial splitting and morphology of the fracture breaks look similar to many fracture breaks that occur in actual use, implying that rotational biaxial tests are useful for predicting fibre degradation in many applications. Furthermore, various severe fatigue parameters and environments can influence fibre fatigue lifetimes.