Experimental Determination of Machining Responses in Machining Austempered Ductile Iron (ADI)

This work investigates the machining characteristics of Austempered Ductile Iron (ADI) using Electrical Discharge Machining (EDM) process with copper as an electrode. Experiments have been carried out to analyze the effect of each parameter on the machining characteristics, and to predict the optimal choice for each EDM parameters such as peak current, pulse on time, pulse off time and tool geometry. Three different specimens were austenised at 900 degrees C for 90 min and then austempered in a salt bath at 360 degrees C, 380 degrees C, and 400 degrees C for 120 min. Experiments have been designed as per Taguchi's L-18 orthogonal array. Analysis of variance (ANOVA) is used to find the level of significance of machining parameters. Machining responses such as the metal removal rate (MRR), Tool wear rate (TWR), surface roughness (SR) and taper angle (DVEE) for entrance exit of the tool was studied while machining the Austempered Ductile Iron (ADI) with copper as an electrode. Discharge current, Pulse on time and Austempering temperature are found most influential parameters on each performance measure. Tool geometry is found the least influential parameters. (C) 2013 The Authors. Published by Elsevier Ltd. Selection and peer-review under responsibility of the organizing and review committee of IConDM 2013