Polymer, metallic and ceramic materials in fibrous form are of fundamental importance in materials engineering. Fibrous materials are the basic building blocks for the backbone of most natural and man-made engineering structures, ranging from the skeletal structure of animals to advanced fiber-reinforced composites.

Fiber assemblies normally known as textile materials are unique in their combination of strength and toughness, lightweight, flexibility and cost effectiveness. As an essential requirement to fiber and fiber assemblies, mechanical properties are one of the most important properties that need to be characterized and investigated. In this chapter, we will consider the mechanical properties of fiber assemblies from single fiber to fiber assemblies in a hierarchical manner.

Structure of hierarchy of textile materials

Traditionally fibers are defined as soft materials with a length-to-diameter ratio above 103 and a diameter ranging from several to 100 microns. The emergence of nanofibers broadens the span of fibers to the nanoscale world.

For engineering applications, fibers are usually employed in different forms such as yarns/ropes, woven textiles and nonwoven textiles. The structure hierarchy of textile materials is shown in Fig. 5.1.