Near Net Shape Manufacturing of Miniature Spur Brass Gears by Abrasive Water Jet Machining

Abstract

This chapter specifically reports a part of the detailed investigation conducted on near net shape manufacturing of miniature spur brass gears by abrasive water jet machining (AWJM). The machined miniature gears are external spur type and have 8.4 mm pitch diameter, 12 teeth, and 5 mm thickness. A total of 9 experiments (with two replications each) have been conducted based on Taguchi’s robust technique with L9 orthogonal array. A detailed analysis of the effects of three important AWJM parameters i.e. water jet pressure, abrasive mass flow rate and stand-off distance on surface quality i.e. micro-geometry (profile error) and surface roughness (mean roughness depth) of miniature gear has been done. Water jet pressure is found to be the most significant parameter affecting surface quality of miniature gears. This chapter reports the effect of AWJM parameters on micro-geometry of miniature gears and optimization of AWJM process to produce the best surface quality of miniature gears using Desirability technique. Miniature gear machined at optimum AWJM parameters possesses high surface quality with profile error 14.15 μm and mean roughness depth 4.6 μm. Based on the profile error value, this gear is assigned manufacturing quality of German standard DIN-8 which is better than that produced by conventional processes. Investigation reveals the capability of AWJM to manufacture near net shape miniature gears and identifies this technology as a sustainable alternate to the conventional processes of gear manufacturing.