Some aspects of centrifugal force assisted abrasive flow machining of 2014 Al alloy

Abstract

Finish machining of precision components constitutes one of the most challenging and expensive stages in a manufacturing process. Abrasive flow machining (AFM) is a non-traditional machining technique that deburrs, polishes, and radiuses surfaces and edges by flowing an abrasive-laden medium over these areas. The process is used in particular for internal shapes that are difficult to process by other non-conventional machining processes. A low material removal rate happens to be one serious limitation of this process. This paper discusses a few of the issues arising when attempting to enhance the capabilities of the conventional AFM process. In this process, a centrifugal force is imparted to the abrasive particles in the medium, making the process a hybrid one. The set-up has been suitably modified for this purpose, and the resulting process is called centrifugal force assisted abrasive flow machining (CFAAFM). The effect of key parameters on the performance of the process has been studied through response surface methodology (RSM). Relationships were developed for material removal and percentage improvement in surface finish of cast Al alloy (2014) cylindrical components. Analysis of variance (ANOVA) has been applied to identify significant parameters. Experimental results indicate the significantly improved performance of CFAAFM over AFM in terms of enhanced surface finish and material removal. It was observed that the combination of a high extrusion pressure and a higher speed of the centrifugal force generating (CFG) rod is more favourable to obtain a higher degree of surface finish, while the combination of a larger grain size and a higher speed of the CFG rod causes higher material removal.