Modeling of the effect of ATH fillers on the rheology, curing kinetics, and flexural properties of the epoxy resin forming the hydraulic turbines’ stay vanes extension

Abstract

Epoxy resins are crucial for the production of GFRP/XPS foam sandwich structures used for hydraulic turbine extension stay vanes. The quantity and size of ATH fillers have a significant impact on the curing and post-curing characteristics of the epoxy resin. This paper presents the results of an experimental study of the effect of ATH fillers on the maximum temperature, polymerization time, shrinkage, viscosity, and flexural properties of the epoxy resin. The study also uses regression and neural network methods to develop models to predict these properties based on ATH mass fraction and particle size. The results showed that increasing the mass fraction of ATH with a smaller particle size delayed polymerization and reduced the maximum temperature. The addition of ATH resulted in an improvement of the flexural modulus; nevertheless, it caused a reduction in both the flexural strength and breakage strain. Adding ATH improved flexural strength, modulus, and breakage strain. The models developed in this study had a high correlation between predicted and measured responses, providing valuable information for the design and casting of the proposed sandwich structures.