| 摘要 |
FIELD: metallurgy. ^ SUBSTANCE: it is implemented reheating of slab, containing wt %: C from 0.025 up to 0.10, Si from 2.5 up to 4.0, Mn from 0.04 up to 0.15, solAl from 0.020 up to 0.035, N from 0.002 up to 0.007, S and Se in the form of Seq equivalent S: Seq = S+0.406ùSe from 0.010 up to 0.035, Ti ëñ0.007 and the rest is Fe and unavoidable admixtures, up to 1280C-of temperature of solid solution formation of inhibitory substances or higher, hot rolling, annealing and cold rolling, decarburising annealing, azotising of moving strip, coating made of annealing divider and final annealing, herewith emission rate of N, contained in steel strip after hot rolling in the form of AlN, is equal 20% or lower, middle size of initially recrystallised grains after finishing of decarburising annealing is from 7 micrometre up to less than 20 micrometer, increasing of nitrogen öN, wt % at azotising is in the range, corresponding equation: 0.007-([N]-14/48x[Ti] ëñ öN ëñ [solAl]x14/27-([N]-14/48x[Ti])+0.0025, where: sol Al- acid-soluble aluminium, and content of nitrogen âN1 and âN2 for each surface for 20% depth from surface of steel strip is in the range, corresponding equation: [â N1-âN2] ëñ 0.35, where: â N1, âN2 - azotising volume of correspondingly facial and back surface of strip, wt %. ^ EFFECT: receiving of sheet steel with extremely high magnetic properties. ^ 12 cl, 4 ex,7 tbl, 2 dwg |
