Natural Fiber Reinforcement Preparation

The textile reinforcement form (preform) plays an important role in determining the properties of the final composite/product. The preform formation process provides a precise control of the fiber architecture and orientation using a suitable textile manufacturing technique. While the techniques employed for preparing glass and carbon preforms are well-known, there is a gap in understanding how to prepare natural preforms for composite reinforcements. This chapter discusses the relevant preform preparation techniques and the resulting fiber architecture. Conventional preforms such as spun yarn, woven, knitted, nonwoven, braided, and comingled are illustrated and classified into one-, two- or three-dimensional reinforcements. Non-conventional preform formation techniques used in the automotive industry are also discussed, including, unidirectional tapes, pre-impregnated preforms, and powerRibs. Finally, the structural parameters of each preform and their effect on the final composite properties are explained.