Real-time parameterization of electrochemical machining by ultrasound measurement of the interelectrode gap

This paper discusses the development of an ultrasound technique that enables the continuous, uninterrupted collection of time-resolved data for dissolution valency, interelectrode gap, and overpotential. during electrochemical machining (ECM). These parameters, in combination with the dissolution current, give insight into the ECM process. The accuracy and expediency of this approach has been established using results collected from the ECM of the stainless steel SS410. The enhanced accuracy and resolution offered by this approach has been demonstrated through comparison with established current-time and interelectrode gap-time analysis methods. This superiority has been explained both in terms of the relative accuracy of the analysis methods and the removal of the requirement for the approximation of constant-valency machining. The resulting current-overpotential relationships are sufficiently accurate to give insight into the ECM dissolution characteristics of the steel, as well as providing an improved parameter base essential for increasingly accurate simulation of the ECM process and tool design techniques.