Application of Box Behnken experimental design to analyze the influence mechanism of process parameters on mechanical properties of high-performance thermoplastic composites

Abstract

Composite processing relies heavily on process parameters, which are the key factors that determine the quality of the finished product. In this investigation, carbon fiber (CF)-reinforced polyetherketone (PEK) thermoplastic composites are fabricated through film-fiber stacking and consolidation process. In this method, carbon fabric and polymer film are alternately stacked, and the stacks are then consolidated via compression molding to create a laminate. The mechanical properties of CF/PEK composites are studied in relation to crucial process parameters such as molding temperature, molding pressure, and holding time. To identify the optimal process parameters for CF/PEK fabrication, the tensile and interlaminar shear strengths of these composites were evaluated. Non-linear quadratic equations employing Box-Behnken Design in Response Surface Methodology and validation trials were used to model these features. To obtain the optimal mechanical properties of fabricated composites, the combination of factor ranges was discovered by overlaying contour plots within the practical constraints. The ideal process parameters for achieving maximum mechanical qualities were determined to be around molding temperature of 400°C, a holding period of 60 min, and a molding pressure of 10 bar.