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PET

ENGINEERING THERMO-PLASTICS
There is a range of PET engineering materials. All have high dimensional stability and are resistant to chemicals. It is possible to modify PET with glycol (PETG) to reduce its brittleness and premature ageing.

Engineering thermoplastics are suitable for a range of demanding and high performance applications that are traditionally associated with metals. The most widely used of this group of materials includes acrylonitrile butadiene styrene (ABS), polyamide (PA) also known as nylon, polycarbonate (PC), polyoxymethylene (POM) also known as acetal, and thermoplastic polyester (PET).

Processing
The advantage of thermoplastics is the ease with which they can be injection moulded. Off cuts and scrap can be reprocessed with virgin material without a significant effect on the properties of the material. Acetal and nylon are also suitable for machining. Thermoplastics can be applied as an overmoulding (by injection moulding) onto metal components, such as bike locks, to provide a contoured and ergonomic outer surface.

There is a range of suitable joining processes including welding (ultrasonic and hot plate), mechanical fixings (threads or rivets) and adhesive bonding.

A major advantage of plastics is that they can be removed from the mould finished, and so do not require any additional finishing. Suitable processes for post-mould finishing include spray painting, metal plating and printing.

Relevant Applications
Bike Locks
These engineering thermoplastics are tough and resistant to impact, which makes them suitable materials for certain parts of bike locks. They can be cut through and so are often overmoulded (by injection moulding) onto suitably tough metal components or combined with metal fibres.