Statistical Modelling and Computational Optimization Using Response Surface Methodology

Abstract

This paper investigates the development, characterization and erosion behavior of hybrid epoxy composites reinforced with coir and glass fibers and filled with fly ash particles. The composites were prepared by manual hand lay-up technique with 20 wt.% E-glass fiber and 10 wt.% coir fiber, while the fly ash content was varied at 0, 5 and 10 wt.%.The hardness of the composites increased progressively with filler content with incorporation of fly ash reaching 86 ± 1.5 at 10 wt% fly ash. Air-jet erosion test was performed to study the erosion behavior and the effect of reinforcement content, erodent velocity and impingement angle were investigated using response surface methodology (Box-Behnken Design). The obtained quadratic regression model was found to be in good agreement with experimental data (R2 = 96.80%, adjusted R2 = 91.04%) which was statistically confirmed by ANOVA. Erodent velocity was found to be the most dominant factor affecting the erosion rate followed by impingement angle and reinforcement content. The predicted minimum erosion rate of 0.0013883 g/min was observed at 5 wt.% reinforcement, 1.5 m/sec erodent velocity and 90 ° impingement angle. In general, the addition of fly ash in proper manner improved the hardness and erosion resistance of the composite.