IntermediateTopic 47 of 100Materials & Chemical
Fibre-reinforced polymers
Carbon and glass fibres give high strength-to-weight ratios.
In depth
GFRP (glass: cheap), CFRP (carbon: very stiff and strong, expensive), AFRP (aramid/Kevlar: tough, impact). Fibres give strength, resin gives shape. Orientation sets properties; processes: hand layup, prepreg autoclave, RTM, filament winding, pultrusion.
Key points
- Fibre volume fraction
- Cure cycles
- Galvanic corrosion of carbon with metals
ExampleA modern airliner has over 50% composites by weight in its structure.
Fibre-reinforced polymers offer very high stiffness and strength for their weight, so they are used in aircraft, sports equipment and vehicles.
What is Fibre-reinforced polymers?
Carbon and glass fibres give high strength-to-weight ratios.
Why is it important to understand fibre-reinforced polymers?
Fibre-reinforced polymers offer very high stiffness and strength for their weight, so they are used in aircraft, sports equipment and vehicles.
What makes carbon fibre stiff?
The high modulus of the carbon filaments, which align along the load path and carry most of the force.
What is the advantage of glass fibre?
It is cheaper and less stiff than carbon fibre, but it has good strength, electrical insulation and corrosion resistance.
How is Fibre-reinforced polymers used in practice?
Typical applications include making a carbon fibre bicycle frame that is light and stiff, repairing a bridge column with a wrapped glass fibre jacket and designing an aircraft panel that carries load in one main direction.
What should I learn before Fibre-reinforced polymers?
Study "Composites" first (topic 46 of 100 in Materials & Chemical). It covers the groundwork this topic builds on.
What are the key points of Fibre-reinforced polymers?
Fibre volume fraction. Cure cycles. Galvanic corrosion of carbon with metals.
Can you give an example of Fibre-reinforced polymers?
A modern airliner has over 50% composites by weight in its structure.
What comes after Fibre-reinforced polymers?
The next topic is "Rule of mixtures", which builds directly on this one.
How difficult is Fibre-reinforced polymers?
It is classed as Intermediate in Materials & Chemical (topic 47 of 100). It is an intermediate topic. Work through the beginner topics in Materials & Chemical first.