Effect of Finishing Time on Surface Finish of Spur Gears by Abrasive Flow Finishing (AFF) Process

Abstract

Abrasive flow finishing (AFF) is an advanced finishing process for deburring, polishing and radiusing of difficult to reach surfaces and object having complex geometrical shape. Surface finish and material removal in AFF process are significantly affected by the finishing time. This paper reports the effect of finishing time on surface quality and material removal rate of spur gear made of 20MnCr5. An experimental setup has been designed and developed for AFF of spur gears using hydraulic power pack unit, medium cylinder and a specially designed fixture for finishing of gear teeth. The fixture ensures proper holding of workpiece gear and direct abrasive medium to flow over entire face width of the workpiece gear uniformly. The results obtained show the highest improvement in surface roughness and material removal rate at 25 min of finishing time. The scanning electron microscope (SEM) images and bearing area curve (BAC) shown improvement in the flank surface quality of gear without any undesirable effect and improved noise and vibration characteristics. All these results have proven AFF as a viable and productive alternative gear finishing process.