Influence of online-heat preservation of cast strip on microstructure and magnetic properties of 4.5wt%Si non-oriented electrical steel in strip casting

The twin-roll strip casting 4.5wt.% silicon steel with equiaxed crystal structure was subjected to online-heat preservation treatment at 1323 K for different times to adjust the various structures of the cast strip. By comprehensively analyzing its cold-rolled microstructure, recrystallization and texture evolution, the formation of recrystallized texture and its impact on magnetic properties were determined. Through process optimization, the iron loss is reduced by 1.97 W/kg after 60 min of online heat preservation. This study provides an effective method for optimizing microstructure and texture of the as cast strip, and proves that appropriate online-heat preservation of cast strips is beneficial to the improvement of the magnetic properties of 4.5wt.% Si electrical steel.