February 6, 2026
Polyamide 6 (PA6) is a widely utilized engineering thermoplastic prized for its high mechanical strength, excellent wear resistance, and inherent self-lubricating properties. To consistently produce high-quality parts, precise control over the injection moulding process parameters is essential.
Temperature Control is paramount. The barrel temperature should generally be set between 220°C and 260°C. The nozzle temperature is kept slightly lower to prevent material drooling or premature solidification. A mould temperature in the range of 70°C to 90°C is recommended, as it enhances melt flow, minimizes internal stresses, and improves the part's dimensional stability and surface finish.
Injection Pressure and Screw Speed must be tailored to the part's geometry and wall thickness. Sufficient injection pressure ensures complete cavity filling, but excessive pressure can cause flash or part distortion. Similarly, screw speed should be optimized; too high a speed generates excessive shear heat, potentially degrading the polymer.
Cooling Time and System Design are critical for cycle time and part quality. Adequate cooling time ensures the part is fully solidified before ejection. An efficiently designed cooling system promotes uniform heat removal, shortening the cycle while preventing defects. During demoulding, careful ejection is necessary to avoid surface marks or cracking on the still-warm part.
Raw Material Pre-treatment is a vital, often overlooked step. Due to its hygroscopic nature, PA6 resin must be thoroughly dried before processing. Typical drying involves heating the material at 80°C to 100°C for more than four hours to achieve a moisture content below 0.3%. This prevents processing defects like splay marks (silver streaks), bubbles, or a loss of mechanical properties.
In summary, by meticulously managing these key parameters—temperature, pressure, cooling, and material preparation—manufacturers can fully leverage the advantages of PA6, ensuring the production of robust, precision-moulded components that meet stringent design specifications.
