Polyamide (PA) are semi-crystalline polymers.
There are two types. Polyamides composed of two base materials (e.g., PA 6.6 and PA 4.6) and polyamides composed of a base (e.g., PA 6 and PA 12). Polyamides have a very good mechanical properties, a particularly high toughness and excellent sliding and wear behaviour. The properties vary from hard and tough PA 6.6 to soft and flexible PA 12. Depending on the type, polyamides absorb different amounts of moisture, which influences their mechanical properties and dimensional accuracy.
In the production of semi-finished products a distinction is made between the extrusion and the casting process. In the casting process, polyamide semi-finished products with larger dimensions and higher degree of crystallization (mechanical strength) can be produced, which also contain less internal stresses. The extrusion process, however, allows a more cost-effective production.
- High mechanical strength, stiffness, hardness and toughness
- Good fatigue resistance
- High mechanical damping capacity
- Good sliding and emergency running properties
- Very high wear resistance
- Good electrical insulation properties
- High resistance to high-energy radiation (gamma and X-rays)
- Good machinability
- High water absorption
PA 6 cast, in contrast to the extruded polyamide types, is available in a pressure-free…
PA 6 E
This material offers an optimal combination of mechanical strength…
PA 6.6 is the material with the greatest hardness and rigidity among the unreinforced PA types…
Polyamide 4.6 (PA 4.6) is a semi-crystalline, thermoplastic material with very high…
PA 12 cast is produced in the unpressurised casting process. Through this…
PA 12 is extruded compared to the other PA types…
Polyamides can absorb up to 7% of their weight in water at high humidity or when stored in water. This can result in a size change of up to 2% and a corresponding deterioration in the physical properties of the material. This effect must be taken into account when designing and defining the tolerances.