Optimization of Characteristics in Electro Discharge Machining of OHNS Tool Steel using Anova Technique
Electro-Discharge Machining is one of the non-traditional machining processes used to produce critical shape on
hard or brittle conductive materials and it can also be successfully applied on materials that are extremely difficult-tomachine
using traditional machining processes. OHNS-O2 tool steel has growing range of applications in industries which
offer difficulty in conventional machining in hardened condition. Influence of various process parameters on material
removal rate, tool wear rate and surface roughness has been investigated during EDM of OHNS-OS tool steel using graphite
electrode. The experimental study evaluates the influence of discharge current, gap voltage, pulse on time and pulse off time
on machining of OHNS-O2 tool steel. Discharge current and pulse on time affects the most for machining and the
performance characteristics. To optimize process parameters in terms of multi performance characteristics of material
removal rate, tool wear rate and surface roughness, the grey relation analysis along with Taguchi approach, which is known
as Grey-Taguchi method has been employed. The confirmation experiments have been performed to check the validity of
grey-Taguchi method. All this experimental observations and subsequent data analysis study assures that GRA method is a
powerful and most versatile tool which can manipulate the input data as per requirement and comes with results that can be
used to have best multi performance in respective concerns.
Keywords - Electro-Discharge Machining, OHNS-O2, Taguchi, Grey Relational Analysis.