Composites are heterogeneous materials composed of two different materials with different properties, each with its own mechanical purpose. Composite composition allows one to combine the good properties of the individual materials. Important composites are the 'fibre-reinforced plastics', which are combinations of resins and reinforcement fibres . They are an interesting alternative to several traditional materials because they are both strong and lightweight. Today, composite materials are found in all sectors of industry, ranging from automotive, construction to marine, aerospace etc.