Experimental Study On Electrochemical Grinding Of K424Cast Nickel-base Superalloy

Electrochemical grinding(ECG) is an effective process combining electrochemical machiningand mechanical grinding, which is often used to produce holes on difficult to machine material. In thispaper, ECG of K424Cast Nickel-base Superalloy was studied, and the influencing factors andelectrode fabrication were discussed. The tests indicated that holes on the material of K424CastNickel-base Superalloy can be produced by using the method of ECG, with high efficiency and highquality.In this paper, the affection of machining quality and stability by using different experimentalparameters was researched toward to K424Cast Nickel-base Superalloy. The following work hasbeen done:(1)The property of K424Cast Nickel-base Superalloy was introduced, and the method of ECGwas presented.(2) An experimental system of ECG has been structured, and the tool electrode, fixture,electrolyte circulation system were designed. Then the flow field and electrolyte were optimized.(3)Improving the accuracy and surface finish of the three-quarters hole was an importantresearch issue for the hole machining．In this paper，the electrochemical grinding technology wasemployed in reaming the three-quarters hole on K424Cast Nickel-base Superalloy, and the effects ofthe voltage, feed rate, concentration of electrolyte and pulse power for the machining quality wereanalyzed. Experiment results showed that the high quality three-quarters hole can be produced byselecting suitable processing parameters: pulse power with50%duty ratio and2kHz pulse frequency,voltage of14V, the electrolyte of16%NaNO3,1.0mm/min feed velocity of diamond grinding heads,the spindle speed of2800r/min.(4) Using the method of uniform design, affecting factors on surface roughness and machiningaccuracy were studied in this experiment. Better experimental parameters were gained. The workpieces with good surface roughness and machining accuracy were obtained with these optimizedparameters, as a result, the high efficient machining of K424Cast Nickel-base Superalloy wasrealized.