High-strength low-iron-loss electrical steel accomplished by Cu-rich nanoprecipitates

Electrical steel used in high speed motors and motors of electric vehicles and hybrid electric vehicles requires both good magnetic properties and high strength. Existing High-strength electrical steel (HSES) usually sacrifices magnetic properties to increase its strength. In this work, a new state-of-the-art HSES with excellent comprehensive performance is presented in which Cu-rich nanoprecipitates are used to strengthen the alloy. The precipitation behavior of Cu-rich precipitates was investigated by solution treatment and aging processes, and the results showed that the Cu-rich nanoprecipitates dramatically improved the yield strength without deteriorating the magnetic properties. A yield strength of 728 MPa and an iron loss P1.0T/400Hz of 15.05 W/kg were obtained, and the ratio of the yield strength to iron loss in this work is over twice that of commercial HSES materials.