Study Of Internal ELID Grinding Based On The Active Control Of Wheel Radial Chatter

Due to the poor process condition, it is hardly for internal grinding to guaranteeprocess precision, so that it is necessary to honing and polishing on the workpiece.However, these processes will significantly increase the cost and decrease theefficiency. Electrolytic In-process Dressing (ELID) grinding is an efficient and preciseprocess method because of its perfect dressing function on wheel. Therefore, an ELIDinternal grinding system was built by numerical reconstruction of a common grinder,including dressing electrode, conductive wheel and software programming.Wheel radial chatter during grinding process will directly affect processefficiency and precision. The oxide layer formed on wheel surface would play a roleof damper so that the chatter could be suppressed to some extent during ELIDgrinding. Therefore, the oxide layer state has a great influence in grinding efficiencyand quality in the ELID grinding. Firstly, the effect of duty cycle adjustment onchatter is analyzed in different state of oxide layer. Results show that in all oxide layerstates, the chatter will increase with the decreasing of duty cycle, and the chatterincrement is bigger when the oxide layer is thinner. Then, a series of active controllersare designed to stabilize the chatter during ELID internal grinding. Last, underdifferent chatter set-point, the grinding performance is studied in the active controlexperiments. The results show that good surface finish and low material removal ratecan be obtained with smaller chatter set-point; poor surface finish and high materialremoval rate can be obtained with larger chatter set-point.