Research on gray correlation evaluation method for ultrasonic cavitation anti-cavitation performance of epoxy resin materials

Abstract

Epoxy resin materials are widely used due to their high cavitation resistance. This study tested nine types of epoxy resin materials using an ultrasonic cavitation device in accordance with ASTM G32–16. Different indicators are used to evaluate the cavitation resistance of materials based on their variations, forming a comprehensive evaluation system that spans from the macro to the micro level. By observing the evolution of material surface morphology, the following patterns have been identified: The diameter of the cavitation pit possesses a critical length and is influenced by the aggregate's diameter; the pitting rate diminishes over time for a constant pit diameter, decreases with an increase in pit diameter over the same duration, and progressively shifts towards larger pit diameters. Characteristic pitting rate and cavitation pit area are inversely correlated with the material's cavitation resistance. Under SEM observation, the aggregate influences the morphology of cavitation damage and the crack distribution in the material. It was found that the cavitation damage morphology of coarse aggregates exhibits a regular, step-like distribution, while the epoxy matrix shows an irregular distribution. The epoxy glue content and epoxy resin-curing agent ratio of the two variables have a high degree of correlation, and both have a linear relationship with the anti-cavitation indicators, according to the analysis, which was based on the gray correlation method to examine the extent to which various material variables influence the anti-cavitation indicators. The evaluation method proposed in this paper provides valuable insights for enhancing material cavitation resistance from a material composition perspective.