Materials Selection Strategy and Surface Treatment of Polymer Composites for Wind Turbine Blades Fabrication

In the present work the optimal materials selection for wind turbine blades using the Cambridge Engineering Selector (CES) program was carried out. Materials indices were derived, based on the mechanical, physical properties and environmental circumstances. Glass and carbon fibre reinforced plastics (epoxy matrix) showed high materials indices based on combined analysis of power and efficiency, fracture toughness, fatigue and thermal stability. Epoxy-glass fibre (EGF) and epoxy-carbon fibre (ECF) composites were manufactured and investigated. Surface of glass and carbon fibre was chemically modified using gamma-aminopropyltriethoxysilane (Silane A1100) coupling agent. The fibre content was varied between 12 to 70% w/w. It is found that the addition of (Silane A1100) as a compatibilizer caused further amelioration of the fibre/matrix bonding resulting in improved mechanical behaviour, which was also, assessed using scanning electron microscopy. Mechanical properties of treated and untreated epoxy composites were illustrated using CES program. Tensile strength of EGF composites was varied based on fibres surface treatment and loadings. Tensile strength of silane treated EGF (70% wt/wt) increased to 1.46 GPa comparing with 1.38 GPa of untreated EGF. The potential and applications of this class of composite materials promise a significant opportunity for improving structural properties of wind turbine blades.