WIRE ELECTROCHEMICAL MACHINING

A NEW MACHINING TECHNIQUE, DESCRIBED AS A CROSS BETWEEN A WIRE EDM (ELECTRIC DISCHARGE MACHINE) AND AN ECM (ELECTROCHEMICAL MACHINE), IS BEING INVESTIGATED. THE METAL REMOVAL PROCESS INVOLVES THE ANODIC DISSOLUTION OF THE WORKPIECE IN CLOSE PROXIMITY TO A MOVING WIRE, SIMILAR TO THE SPARK EROSION MACHINING OF A WORKPIECE PRODUCED BY A MOVING WIRE IN CURRENTLY AVAILABLE WIRE EDM EQUIPMENT. ONE DISADVANTAGE OF THE EDM PROCESS RESULTS FROM THE THERMALLY PRODUCED STRESS ON THE SURFACE OF THE PART WHICH LIMITS THE MINIMUM PART THICKNESS AND IS DETRIMENTAL TO FATIGUE LIFE. THE SURFACE FINISH PRODUCED BY EDM IS ALSO INVERSELY PROPORTIONAL TO CUTTING SPEED. THE ECM PROCESS LEAVS A STRESS-FREE SURFACE WITH A SURFACE FINISH WHICH CAN ACTUALLY IMPROVE WITH CUTTING SPEED. CUTTING RATES FOR A WIRE ECM PROCESS WHICH WOULD BE COMPARABLE TO CURRENT WIRE EDM PROCESSES CAN BE OBTAINED. INVESTIGATION INTO MATERIAL RELEVANT TO THE PROCESS IS PROVIDED ALONG WITH ANALYTICAL AND TEST RESULTS ON A FABRICATED TEST APPARATUS.