Polyamide plastics have good mechanical characteristics. They are tough with good fatigue and creep characteristics, have a low friction coefficient and are resistant to wear. They are resistant to many solvents, including chlorinated hydrocarbons, alcohols and esters. They are also resistant to most bases. However, PA cannot handle strong acids and strong oxidising agents, such as chlorine and aromatic alcohols. Polyamide plastics take up water. It acts as a softening agent and changes the material’s dimensions and characteristics. Among other aspects, the electrical characteristics are affected, which is why their use as electrical insulators is not recommended. Destabilising qualities of PA are sensitive to UV light and heat. With fibre glass, greater tensile strength and rigidity can be achieved. The dimension stability also increases and moisture uptake decreases.
Advantages:
- Good combination of mechanical and chemical characteristics.
- Good wear resistance
- Withstands relatively high temperatures
- Can be steam sterilised
- Good chemical resistance
- Some characteristics can be improved with the help of fillers
Limitations:
- All polyamides absorb or emit moisture, which changes the material’s characteristics.
- Linear expansion varies with temperature and moisture content.
- UV radiation makes polyamides brittle.
- Corroded by strong mineral acids and acetic acid, dissolved by phenols. Some types are corroded by formic acid.
Abbreviations:
PA
Colouring options
Almost unlimited
Common applications
Gear wheels, screws, bearings, propellers, machine hoods, etc. Note: Available in many variants, e.g. PA 6, 6.6, 6.10, 12, etc.