PA Nylon is a semi crystalline thermoplastic with low density and high thermal stability. Polyamides are among the most important and useful technical thermoplastics due to their outstanding wear resistance, good coefficient of friction, and very good temperature and impact properties. In addition, nylon polyamide exhibits very good chemical resistance and is a special oil resistant plastic. This excellent balance of properties makes the PA polymer an ideal material for metal replacement in applications, such as automotive parts, industrial valves, railway tie insulators and other industry uses, whose requirements include high strength, toughness, and weight reduction. Nylon plastic shows a propensity to absorb moisture and thus has poorer dimensional stability than other engineering plastics. Polyamide properties vary from the hard and tough PA 66 to the soft and flexible PA 12. Depending on the type, polyamide products absorb differing amounts of moisture, which will, in turn, affect the nylon properties, in addition to the dimensional stability of the finished machined part.
Furthermore, there is a distinct difference between nylon shapes produced by extrusion and those produced by casting. Extrusion typically provides for smaller, higher volume machined parts, while casting typically allows for low volume, larger parts containing lower levels of internal stress. Both extruded and cast nylons can be modified using fillers to enhance certain properties.