Use of composite materials in Automotive
The automotive industry has two very distinct parts: the large-volume sector and the specialist area producing modified or complete vehicles in small numbers. The challenges of each are different and this is reflected in the way car manufacturers approach the use of composites.
In the large-volume sector, a large percentage of the cost is in the capital plant needed for manufacture and so once the required equipment has been procured and commissioned it is very costly to change the design of a component. This naturally makes the industry very conservative, and encourages extensive prototype testing in both real and simulated environments of any new system before the investment is made.
In small-volume production, however, the manufacturing operations are much less capital intensive and so the resistance to change in material is somewhat less.
The main advantages composites offer the automotive applications are in cost reduction, weight reduction and recyclability. Composites offer many structural and weight advantages over traditional steel and injection moulded automotive parts.
Compared to thermoset based composites, thermoplastic materials offer the automotive industry key advantages: zero-solvent emissions, reduced material scrap, improved work safety conditions, elimination of painting steps (through use of high-molecular weight polymer surface films), elimination of tedious production steps via automation, and finally greatly improved recyclability.
Thermoplastic composites offer excellent crash performance compared with traditional steels. While steel typically absorbs only 35J/kg of energy, thermoset composites can absorb about twice this, and thermoplastics can absorb 7-8 times the energy of steel (C-PEEK = 230J/kg).
Based on European directives and standards (2000/53/EC-End Life of Vehicles), the automotive industry must address many issues including:
- Environmentally friendly dismantling and recycling of vehicles
- Increased reuse, recycling and recovery of vehicles and their components
- Manufacture of new vehicles with enhanced recyclability
- This offers great potential for application of thermoplastic composites into automotive markets.