Optimization of Electro Chemical Machining of ASTM 52100 Bearing Steel (100 Cr6) for Machining Time, Surface Roughness and Kerf Angle

Abstract

Various types of Steel alloys are available in market, each of whose utilization varies with amount of different elements it contains. ASTM 52100 Steel or 100Cr6 Bearing is a specific type of steel alloy (with high carbon contents along with chromium contents) which has been hardened. It is mainly used in the fabrication of different bearings because of its higher wear resistance and good fatigue life. Grooves are fabricated on bearings for the purpose of self-pumping of lubricant to reduce friction and increase wear life of bearings. In this thesis, electro-chemical machining method of fabrication of grooves on bearings is worked upon. In electro-chemical machining, the work piece which is often rendered anode is placed in a bath of electrolyte solution along with the cathode and DC current is supplied through variable power supply. Electro chemical reaction takes place in the bath and metal from the work piece is dissolved in the solution. In this thesis work, grooves with micro depth are fabricated on samples of 100Cr6 Bearing steel and the factors on which electro chemical machining depends (electrolyte concentration, current, temperature of solution) are varied to get responses in terms of time required to machine 10 micron depth, surface roughness of etched area and kerf angle of the groove machined. These responses are optimized subsequently.