On ultrasonic assisted abrasive flow finishing of bevel gears

Finishing of bevel gears is an important requirement in many machining shop floors. Variants of abrasive flow machining (AFM) could be plausible solutions for finishing such parts with intricate geometries. In the present work, a relatively new variant of AFM called ultrasonically assisted abrasive flow machining (UAAFM) technique was employed to finish bevel gears made of EN8 steel. An analysis of the process has been presented with suitable illustrations. A finite element simulation of the behavior of the medium during finishing of bevel gears using the UAAFM process has been presented. A 3D model was constructed to simulate the flow of medium through the outer wall of the gear tooth surface using computational fluid dynamics (CFD) approach. The velocity, pressure and temperature values along the length of the workpiece were computed for both UAAFM and the conventional AFM processes. Further, the effectiveness of the process was investigated through experimental trials by conducting a comparison study between classical AFM and UAAFM. Ultrasonic frequency, extrusion pressure, processing time and the media flow rate were considered as the input variables while improvements in surface finish and material removal were considered as the monitored outputs. Results confirm that improvements in surface roughness and material removal are significantly higher than those obtained with conventional abrasive flow machining. The study further reveals that, the applied high frequency (ultrasonic) vibration to the workpiece has the maximum influence on the process responses among the variables considered. (C) 2014 Elsevier Ltd. All rights reserved.