Composite materials are, by definition, structures made up of several component materials. In technical “slang” this name is usually identified with materials consisting of thermoset resins strengthened with carbon, Kevlar or glass fibres. In practice, however, there are composite materials made from thermoplastics, plant fibres or inert materials, though in each case they respect the basic combination of a fibrous structure offering certain characteristics (usually mechanical) and a matrix that holds the fibres in position, protects them and offers other specific characteristics for particular applications.
The main purpose behind the development of these materials is, without a doubt, their high ratio between density and mechanical strength, letting one get performance levels similar to those of metal (or even higher), but at far lighter weights (even 50% less).
In recent years the chemicals and textiles industries have made great advances in the development of new fabrics with increasingly complex reinforcement – fabrics that satisfy a huge range of functional needs – and resins that allow these composite materials to work efficiency in many different environments.
Laminated composite materials can be imagined as sheets of continuous strands of fibre, layered so that each fibre lies in a specific direction. This means that reinforcement is only added where needed and so the amounts of material used can be optimised and thus the weight of each product kept to a minimum.
|HIGH STRENGTH CARBON||MG AZ91 ||AL A380||1020 STEEL||PC/ABS ||PP ||PP 30% |
|Shear strength (MPa) ||5.000||160||165||330||58||35||90|
|Modulus of rigidity (GPa) ||230||45||71||203||2,2||2,5||9|
|Ultimate tensile strength (%) ||2||3||3||36||122||150||3|
|Specific resistance (*)||2.778||88||62||42||52||39||74|