Influence of recrystallizing annealing on the properties of high-alloy isotropic steel with ultralow magnetic losses

Abstract

A technology is developed for the production of highly alloyed (with up to 3% Si) isotropic electrical steel characterized by ultralow magnetic losses (P_1.5/50 ≤ 2.70 W/kg for strip of rated thickness 0.50 mm). The structure, texture, and magnetic and mechanical properties of vacuum-treated (<0.005% C) cold-rolled strip consisting of high-silicon steel (alloyed with >1% Al and >0.015% Sb) is investigated as a function of the heating rate and also the temperature and holding time in recrystallizing annealing. By refining the boundary conditions in the recrystallizing annealing of cold-rolled isotropic electrical steel, optimal grain size is obtained, and the pole densities of cubic orientations in the texture are increased. That reduces the magnetic losses.