Layup Design Optimization for E-glass Woven Roving Fabric Reinforced Polyester Composite Laminates Produced by VARTM

In this study, a satisfactory number of actual test results were used to optimize the stacking sequence design of bidirectional glass-woven fabrics in polyester composite laminates. In optimization, parameters such as glass-woven fabrics with five different areal weights, stacking sequence, number of plies (PLY), and off-axis fiber directions (DEG) were taken as input factors. Values such as tensile strength (UTS) and flexural strength (UFS), mechanical anisotropy factors (AFs), and resin permeability coefficient of stacked glass-fabrics were taken as output responses. In this study, a laboratory-scale vacuum assisted resin transfer molding (VARTM) process was established. Composite laminates with sixteen different stacking and six different number of plies are produced. Mechanical properties such as tensile and three-point flexure have been tested for the composite laminates obtained. In addition, the resin permeability coefficient for each laminate and the AF for tensile and flexural module depending on fiber direction were calculated during production. Many actual test data were obtained versus response to seven factors and five variables. Instead of the experimental designs recommended in response surface methodology (RSM), 64 actual test data were used as responses of the model. In the optimization with the Minitab, the minimum mechanical AF was desired in return to maximum UTS, UFS, and permeability coefficient. Optimum stacking sequence, PLY, DEG, permeability coefficient, and AFs were determined through using RSM. Consequently, the most optimal composite laminate was suggested in real terms in the desirability rate of laminate D=0.6731 with the stacking sequence of [822252]6, six plies, and 0 °/90 ° fiber direction.