Integrated FEA and Taguchi-based injection moulding optimisation of a glass fibre-reinforced nylon automotive bracket: a simulation-based study

This simulation based-study presents an integrated computational framework that links injection moulding process optimisation with the thermo-mechanical performance of a glass fibre-reinforced PA66 automotive throttle cable bracket. Unlike conventional approaches that optimise moulding parameters solely based on flow-related responses, this work establishes a quantitative process–performance relationship by coupling mould-flow behaviour with structural response under realistic service conditions. Finite element analysis (FEA) was conducted to evaluate the influence of mechanical loading (50–150 N) and temperature (23–120 °C) on component performance. It was found that temperature is the dominant factor, with stress increasing significantly from 4.041 MPa at 23 °C to 104.600 MPa at 120 °C due to temperature-independent properties with stresses from constrained thermal expansion effects. The effects of the processing settings on shear stress at the end of fill, filling time and weld line were further studied using a Taguchi L27 orthogonal array. The channel shape was shown to be the major element affecting the flow behaviour. It was observed that an elliptical channel reduced the shear stress to 0.38 MPa and fill time to 4.135 s. Lower shear stress and better flow uniformity reduce fibre degradation. This helps to improve structural integrity at higher temperatures. Injection pressure was the sole statistically significant factor impacting the weld line angle. This study presents a performance-driven optimisation technique for injection-moulded composite components by directly correlating moulding parameters to thermo-mechanical performance. This approach could identify processing parameters that enhance both manufacturability and in-service reliability, providing practical insights for the design of high-performance polymer components for automotive applications.