Texture evolution of Nb micro-alloyed Fe14Si2high silicon steel during warm rolling

Abstract

Fe-6.5%Si (mass fraction) alloy possess perfect magnetic properties, though inter-metallics 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%.