Experimental determination of viscosity of abrasive flow machining media

Abrasive flow machining (AFM) is a non-traditional process used to de-burr, radius, polish and remove recast layers of the components in a wide range of applications. The material removal in abrasive flow machining takes place by flowing the media, mixed with abrasives, across the surface to be machined. The media is the key element in the process because of its ability to precisely abrade the selected areas along its flow path. From the review of literature, it was found that there is a need to know the viscosity of the media, since it has a significant effect on the process performance parameters. In the present work, a viscometer set-up has been fabricated based on the principle of visco-elasticity. The creep compliance and the bulk modulus have been determined and the viscosity of the abrasive media has been subsequently calculated. Measurements have been conducted for obtaining viscosity along with an assessment of specimen length and initial load, the influence of reduced data points and the repeatability of the experiments. Besides this, experiments have been conducted at varying concentration and temperature of the abrasive media. Experiments show that the viscosity of the media increases with the percentage concentration of abrasives and decreases with temperature. Viscosities at different concentration of the abrasives were compared with the values obtained from a capillary viscometer and the comparison was found to be good.