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PA

ENGINEERING THERMO-PLASTICS
PA, commonly known as nylon, is a versatile material used in a wide range of applications. Aromatic polyamides are stronger than steel for their weight. There are many different grades of nylon, which are categorised as follows: nylon 6; nylon 6.6; nylon 6.12; amorphous nylon (transparent); and high temperature nylon. These grades can be modified in a number of different ways to produce reinforced, flame retardant, tough and super-tough versions. Nylon is self lubricating, has a low coefficient of friction, and has good resistance to abrasion and chemicals.

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.