Optimization of EDM Parameters on Machining Si₃N₄–TiN Composite for Improving Circularity, Cylindricity, and Perpendicularity

Abstract

The dominance of the spark eroding process in complex ceramic components has promoted a significant growth analysis in the ceramic composites domain in modern manufacturing industries. The latest developments in ceramic components are concentrated on both the enhancement of the mechanical properties and the machinability of complex 3D parts while using spark EDM. The current (I), pulse on time (T on ), pulse off time (T off ) and dielectric flushing pressure (DP) are considered sparking parameters for the machining of a Si 3 N 4 -TiN ceramic composite. These composites find their application in high-temperature environments viz. metal forming, extrusion dies, turbine blade and non-ferrous molten metal handling components. Taguchi's orthogonal array (OA), L 18 , has been used to design the experiments. The optimal machining inputs are determined by the grey relational grade (GRG), which is attained from the grey relation analysis (GRA) for various response characteristics, such as the material removal rate (MRR), tool wear rate (TWR), circularity (CIR), cylindricity (CYL) and perpendicularity (PER). The significant parameters are identified via an analysis of variance (ANOVA).Finally, the optimised process parameters resulting in a higher MRR, lower TWR, lower form tolerance, and decreased orientation tolerance are verified through a confirmation test demonstrating that sparking process responses can be effectively improved. Downloaded by [New York University] at 21:49 02 August 2015 2

Simultaneous optimization of drilling responses using GRA on Al-6063/TiC composite

“…Grey relational study is a way of converting two or more output parameters into a single output parameter so as to change the multi-response problem into a singleresponse one [25]. The method of grey relational study is explained in the subsections [26,27].…”

Comparative Experimental and Numerical Investigation on Electrical Discharge Drilling of AISI 304 using Circular and Elliptical Electrodes

“…The bottom interelectrode gap was also manipulated by applying ultrasonic vibrations in the vertical direction [3], [5] and [6]. Moreover, it is reported that increasing electrode rotation [7] to [9] and dielectric pressure [10] to [12] have provided improvements in flushing and drilling performance. In contrast, only a few studies have been conducted for investigating the effect of electrode shape in the EDD process.…”

Architectural design and cryogenic synthesis of Si3N4@(TiN–Si3N4) for high conductivity

“…Electrical discharge machining (EDM) is a cheap and flexible way of mechanical processing, by which materials to be machined need to be conductive (electric conductivity > 2.0 × 10 2 S·cm −1 , with resistivity of <5 × 10 −3 Ω·cm) . Hence, tremendous efforts have been devoted to the research and development of Si 3 N 4 ‐based conductive ceramic by adding a second phase to meet the requirement of EDM, since Si 3 N 4 is an insulator (with resistivity of >10 11 Ω·cm) …”

“…4 Hence, tremendous efforts have been devoted to the research and development of Si 3 N 4 -based conductive ceramic by adding a second phase to meet the requirement of EDM, since Si 3 N 4 is an insulator (with resistivity of >10 11 ΩÁcm). [5][6][7][8] Among these family, titanium nitride (TiN) is considered to be a promising second phase due to its high electrical conductivity (with resistivity lower than 10 À3 ΩÁcm) and good physical properties, such as high hardness, chemical inertness, and low friction coefficient. [9][10][11] Unfortunately, TiN has poor oxidation resistance at high temperature, and oxidation occurs from 650°C resulting in the poor stability of the whole materials at high-temperature conditions.…”