Preparation of non-oriented silicon steel with high magnetic induction using columnar grains

Columnar grains can lead to detrimental surface ridging and an inhomogeneous microstructure, although their {1 0 0}〈0 v w〉 texture is considered desirable due to their good magnetic properties in non-oriented silicon steel. Based on the hereditary tendency of {1 0 0}〈0 v w〉 texture, the effects of lubrication and heating rate on texture and on final magnetic properties were investigated using a cast slab containing 100% columnar grains. Hot rolling with lubrication, normalization at low heating rate, two-stage cold rolling, and final annealing at 1000 °C helped achieve high performance. As a result, a new non-oriented silicon steel with high magnetic induction (B50=1.82 T) and low core loss (P1.5=2.35 W/kg) was prepared. The possibility of further performance optimization was also discussed.

► Advanced non-grain oriented steel with high magnetic induction produced from columnar grains.
► Effect of lubrication and heating rate on structure, texture and magnetic property determined.
► Sample of 0.35 mm thick possesses magnetic properties of P1.5 below 2.50 W/kg and B50 over 1.80 T.