tailieunhanh - Influence of workpiece hardness on EDM performance

(BQ) The aim of this research is to show the influence of the hardness of the alloy steel on the material removal rate and on the workpiece surface roughness. | ARTICLE IN PRESS International Journal of Machine Tools & Manufacture 49 (2009) 744–748 Contents lists available at ScienceDirect International Journal of Machine Tools & Manufacture journal homepage: Short Communication Influence of workpiece hardness on EDM performance ´ ´ Jose Duarte Marafona Ã, Arlindo Araujo ˆ ˜ Departamento de Engenharia Mecanica e Gestao Industrial, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal steel AISI/SAE-D2, a r t i c l e in f o a b s t r a c t Article history: Received 22 October 2008 Received in revised form 13 March 2009 Accepted 13 March 2009 Available online 27 March 2009 The aim of this research is to show the influence of the hardness of the alloy steel on the material removal rate and on the workpiece surface roughness. The Taguchi methodology was used to study that influence. The result of the verification test for workpiece surface roughness was a strong confirmation. This type of outcome allows the use of the additive model to predict the workpiece surface roughness with an average error of . The result of the verification test for material removal rate was a poor confirmation due to an interaction of parameters. This type of outcome does not allow the additive model to predict the material removal rate with accuracy. Therefore, a linear regression model was developed for material removal rate using workpiece hardness and its interactions, among other variables. This model predicts the material removal rate with an average error of . These results show that workpiece hardness and its interactions have influence on the material removal rate and on the workpiece surface roughness. & 2009 Elsevier Ltd. All rights reserved. Keywords: Electrical discharge machining (EDM) Alloy steel hardness Material removal rate (MRR) Workpiece surface roughness Taguchi methodology Linear regression model 1. Introduction Electrical discharge machining