| Abstract: | The influence of punching on the magnetic properties of fully annealed electrical steel sheet with 1 % Silicon has been investigated. By comparing to an Epstein sample, which had its deformed edges carefully removed, it was found that the total power loss increases and the permeability decreases with increasing the specific cut edge. At a length of 100 m/kg the increase P 1.0 is about 30% when samples were cut with a sharp tool and even 40% for a blunt tool. The greatest change of the induction occurs in the range of maximum permeability. At 100 m/kg cut edge the decrease is about 70%: an influence of the clearance on the magnetic properties could not be shown clearly; the area of edge hardening was 0.35 mm in width; there was no influence of tool wear.Original magnetic properties have been obtained after box annealing at 700°C/1 h in dry nitrogen. |
