Development of the improved Preston equation for abrasive flow machining of aerofoil structures and components

Abstract

The paper presents an improved Preston equation, which aims to be part of the industrial application to abrasive flow machining. The equation will aid the engineers to optimise the process for desired surface roughness and edge tolerance characteristics on complex geometries in an intuitive and scientific manner. The methodology presented to derive the equation underpins the fundamental cutting mechanics of abrasive machining or polishing assuming all abrasive particles within the media are spherical as manufacturers defined. Further to derivation, full four factorial experimental trials and computational fluid dynamics simulation are implemented to generate the flow features of media on coupon to evaluate and validate the equation for its competency and accuracy on prediction of material removal. The modified Preston equation can significantly contribute to optimise the abrasive flow machining process, and will advantage the integrated machine design to predict better virtual surface roughness and material removal rates.