Stress annealing process suitable for the production of low permeable nanocrystalline tape wound cores

A possible large-scale fabrication process of nanocrystalline tape wound cores with stress-induced anisotropy is investigated. The common method to pass the tape through a furnace under stress prior to core winding is not suitable due to brittleness of the nanocrystalline tape. We introduce a new method to anneal and apply the stress after core winding. Additionally, magnetoelastic effect is used to achieve cores with defined hysteresis loop and reasonable soft magnetic properties.