Fibres The Basic Properties

Fibrous materials act to reinforce a matrix material by transferring the stress under an applied load from the weaker matrix to the much stronger fibre. Polymers provide valuable and versatile materials for use as matrices. 

Glass is predominantly the most important and widely used fibre in reinforced plastics. Other fibres are natural (cotton, sisal, jute), synthetic (nylon, polyester, acetate, rayon), or organic and Inorganic high-performance fibres (aramid. boron, carbon/graphite). 

Fibres are used mainly in the form of short or long chopped filaments/strands. mats made of random chopped strands, or woven fabrics of varying density. Woven and non-woven fabrics can be used to improve. surface qualities such as appearance, impact resistance, abrasion, and chemical resistance. To improve distribution and orientation of fibres in a three-dimensional moulding, there has been considerable development of preforming techniques, and machine-made three-dimensional arrangements of fibre, which offer better drape in a mould. When more than one fibre is used, the composite is termed a hybrid. 

Fibre/grade Density (gem- ) Tensile strength (MPa) Flexural modulus (GPa) Specific modulus (Mm) 

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