Influence of cutting technologies on the magnetic anisotropy of grain oriented electrical steel

Grain-oriented electrical steels are used in electrical vehicle traction, electric devices such as special motors, transformers and actuators. This type of material presents a strong magnetocrystalline anisotropy that has an important influence on the energy losses and other magnetic properties. It is well known that the classical grain-oriented material has a (110)[001] Goss texture and this structure is produced by a secondary recrystallization with a 3 to 10 mm grain size. The best magnetic behavior of the strips is observed along the <001> crystallographic axis, which is called easy magnetization direction. The worst magnetic properties are determined at an angle of 55° (<111>) with the rolling direction. The influence of the anisotropy is analyzed on samples cut at different angles starting with 0° in step of 15° up to 90°. The samples were cut through a classical mechanical punching, and two non-conventional methods: electro-erosion and laser. The energy losses were measured by means of an industrial Brockhaus single strip tester, in the frequency range from 10 Hz to 100 Hz at a peak magnetic polarization of 1T. The loss separation concept was applied, and the magnetocrystalline anisotropy influence on the hysteresis, classical and excess losses was analyzed.