Process parameter of WEDMoptimized by using Response Surface Methodology

Abstract

A little research has been conducted to obtain the optimal levels of machining parameters that yield the
best machining quality in machining of difficult to machine materials like hot die steel H-11. The hot die steel H-11 is
extensively used for hot-work forging, extrusion, manufacturing punching tools, mandrels, mechanical press forging die,
plastic mould and die-casting dies, aircraft landing gears, helicopter rotor blades and shafts, etc. The consistent quality
of parts being machined in wire electrical discharge machining is difficult because the process parameters cannot be
controlled effectively. These are the biggest challenges for the researchers and practicing engineers. Manufacturers try
to ascertain control factors to improve the machining quality based on their operational experiences, manuals or failed
attempts. Keeping in view the applications of material H-11 hot die steel, it has been selected and has been machined on
wire-cut EDM (Elektra Sprint cut 734) of Electronica Machine Tools Limited. The response surface methodology (RSM)
in conjunction with second order central composite rotatable design has been used to develop the empirical models for
response characteristics. Desirability functions have been used for simultaneous optimization of performance measures.
Also, the Taguchi technique and utility function have been used for multi- response optimization. Confirmation
experiments are further conducted to validate the results