Autoclave process parameters affecting physical properties of carbon fiber reinforced polymer composite laminates using response surface methodology

Process parameters for the autoclave cure method are critical to controlling manufacturing-induced microstructure and composite laminates’ physical and mechanical properties. The effect of temperature, pressure, and vacuum on the degree of cure, density, fiber volume fraction, and void content of laminated composites was investigated by response surface methodology (RSM) and Box–Behnken Design (BBD), along with the application of analysis of variance (ANOVA), to examine the importance of regression models. The results showed that the degree of cure highly depends on the temperature. At the same time, for density, the linear effect of the pressure was the most significant term, followed by the interaction between the temperature and pressure, the quadratic terms of vacuum and pressure, and the linear terms of temperature and vacuum. All the linear terms, quadratic terms of pressure and vacuum, and interaction between temperature and pressure were significant for fiber volume fraction. However, void content has only five significant terms (the linear effect of the pressure followed by all the quadratic terms and the linear term of vacuum). The predicted responses using quadratic models were in good concordance with the experimental values (R² values were above 98% for all responses).