Bruno Kersschot

The electrical behaviour of the dressing process in ELID-grinding

During ELID-grinding, the metallic wheel is kept sharp through an electrolytic dressing process in which a layer is grown on top of the wheel’s surface. The electrolysis process can be modelled electrically using the Helmholtz representation of a boundary layer. Measurements show that at the start of the (pre-)dressing the capacitance of the system is at its highest value, above 10 µF. After a while, it drops significantly to a level below 1 µF. This signifies a change in the metal-electrolyte interface and the grinding wheel is covered with a layer of (hydr-)oxides. The model is refined in two ways. Firstly, the capacitance between the two metallic electrodes is added. Secondly, the self-inductance of the power cables is included. With the proposed model it is possible to properly simulate the electrical behaviour of the growth of the layer. It also provides a fundamental insight into the electrolytic dressing process.