Abstract: Wire electrical discharge machining (WEDM) experiments were performed on nonoriented electrical steel to study the effect of different current density levels on the morphology of the cutting surface. The original morphologies of the surface after cutting were observed with the 3D measuring laser microscope. A scanning electron microscope (SEM) was used to observe the cutting surface with the same level of ultrasonic vibration for measuring the adhesion ability of the adhesion layer. The cutting surface became rougher as the current density level increased. The uniform and smooth smallamplitude raised or recessed regions were gradually replaced by oxidizable and irregular steps, whose height transition zones were nearly vertical. And the bright nearspherical resolidified bodies appear surrounded by oxidized regions at an excessively high current density. Therefore, the high level of current density is harmful for controlling the quality of the cutting surface. On the contrary, WEDM technology with lower level of current density has high advantages.

Key words: non-oriented electrical steel, wire cutting, current density