Precision Finishing of Bevel Gears by Electrochemical Honing

Abstract

This article presents some studies on precision finishing of straight bevel gears using electro-chemical honing (ECH) process. Surface roughness and form errors in terms of pitch and runout error have been studied as process performance measures. An innovative experimental setup has been designed and developed for ECH of bevel gears using a novel concept of twin complementary cathode gears. It ensures finishing of the entire face width of the workpiece gear and the inter-electrode gap required for the ECM action to take place. In this concept, one of the cathode gears has an undercut conducting layer sandwiched between two insulating layers while, in the other cathode gear, an insulating layer is sandwiched between two undercut conducting layers. The results have shown noticeable improvement in the surface finish and form accuracy in an optimized finishing time of 2 minutes. The scanning electron microscope (SEM) images and bearing area curves have also shown improvement in the surface integrity and material contact ratio thus ensuring enhanced tribological performance and maximum service life of the gears. All these results have proven ECH as a viable and productive alternative gear finishing process.

Keywords:

• Electrochemical
• Errors
• Finishing
• Form
• Gear
• Honing
• Hybrid
• Precision
• Surface