TEXTURE EVOLUTION OF Nb MICRO-ALLOYED Fe 14 Si 2 HIGH SILICON STEEL DURING WARM ROLLING

Abstract

Fe–6.5%Si (mass fraction) alloy possess perfect magnetic properties, though intermetallics of Fe14Si2 phase brought 6.5%Si leads to room temperature brittleness and hinder this significant materials industrialization. Nb was adopted into micro–alloying of Fe–6.5%Si high silicon steel. OM, thermal simulated test machine and XRD were employed to study the influence of Nb on high silicon steel in processing stages. Textures of warm–rolled high silicon steel strips were determined by XRD. The results indicate that Nb could refine the grains during fabrication of high silicon steel. Comparing to the non–Nb micro–alloyed high silicon steel, the grain size were reduced 17.50%, 24.51% and 30.13% in as–cast, forged and hot–rolled microstructure. Compression strength of as–cast specimen was enhanced from 1365 MPa to 1520 MPa with elongation rate from 0.225% to 0.400%. Tensile strength of warm–rolled strip was increased from 573 MPa to 621 MPa with elongation rate from 0.018% to 0.026%. XRD was carried out to indicate the surface texture evolution of warm–rolled high silicon steel with thickness from 0.30—1.68 mm during the warm rolling. The original (011)〈100〉 Goss texture totally transformed to (100)〈011〉 rotating cube texture with single pass deformation of 26.2%. Then, rotating cube texture completely transformed to {111} fiber texture which remains until the thickness of 0.30 mm with single pass deformation of 22.6%.