THE EFFECTS OF CARBON CONTENT AND MICROSTRUCTURE ON THE METAL REMOVALRATE IN ELECTROCHEMICAL MACHINING

The present study investigates the effects of carbon content, microstr ucture and working pressure on the metal removal rate and current effi ciency in the electrochemical machining of carbon steels. Four differe nt carbon contents and various heat-treatment procedures (quenching, t empering and annealing) were performed. Some important experimental re sults are shown, as follows: (1) The removal rate and current efficien cy increase with carbon content. (2) The quenched microstructures and tempered microstructures have a greater removal rate and current effic iency than those of the annealed microstructures. (3) The workpiece ma chined at the low working pressure of 3-4 kg/cm2 has the greatest remo val rate and current efficiency. (4) The machined surface roughness of all kinds of microstructure decreases with increase in the carbon con tent. (5) The roughness of the machined surface for annealed microstru ctures is greater than those of the quenched and tempered steels.