DETERMINATION OF SUITABLE ELECTROLYTE FOR MAXIMUM MRR AND THE BEST SURFACE FINISH FOR MACHINING TITANIUM ALLOYS BY ECM

Parameswar Dash

Abstract: The rapid developments in recent years of the advanced technological industries like aerospace, nuclear power etc. has been accompanied by an increasing use of difficult-to-machine alloys like titanium and nimonic. Some Aerospace industries manufacture R-29B engine which is fitted into MIG-27M aircraft. In this engine, six out of eleven stages of compressor rotor blades and compressor stator blades upto fifth stage are made of titanium alloys. A great deal of problems is encountered in machining these blades conventionally because of some inherent mechanical properties.These problems are multiplied due to the complexity of the blade aerofoil surface. All these problems result in frequent resharpening of tools and cams, higher machining times due to lower speed, feed & depth of cuts, higher inventory of tools and incorporation of an intermediate belt grinding process to give required shape, size and finish to the blade. One of the methods of conveniently machining them is by electro chemical machining. (ECM). In this paper, several experiments have been carried out to find out suitable electrolyte(s) among four electrolytes, namely Sodium Chloride (NaCl), Sodium Nitrate (NaNa3), Potassium Bromide (KBr) & Sodium Sulphate (Na2So4) for machining titanium alloys by ECM. Experiments have been conducted by using ANOVA”to optimize the results.

Keywords: ANOVA, Taguchi, ECM, Electrolyte, MRR, SF etc…

DOI: https://doi.org/10.15623/ijret.2015.0412033