Experimental Investigation of Pocket Milling on Inconel 825 using Abrasive Water Jet Machining

Abstract

Rectangular pocket milling is a new area where abrasive water jet machining is being introduced. The current trend abrasive water jet machining (AWJM) process is getting focused on milling applications. In this investigation experiments were carried out on Inconel 825 to check the possibility of using AWJM process for producing 3D features such as pockets of size 20mm x 10mm. A design of experiment approaching Taguchi method was taken considering the input variables such as step over (SO), traverse speed (TS), pressure (P) and abrasive flow rate (AFR) as process parameters they are varied in three levels fixing the standoff distance(SOD) as 2 mm, orifice diameter as 0.35 mm and AMS size as garnet 85# and the obtained output parameters viz., Depth Of Cut (DOC), Material Removal Rate (MRR) and Surface Roughness (Ra) are recorded in two strategies, namely Hatch strategy and Spiral strategy. Analysis of variance is carried out in order to study process parameters interaction and to calculate the F value. The results have shown that the traverse speed and step over influentially affected the output parameters DOC, MRR and Ra.