METHOD OF MAKING PLATE OF TEXTURED ELECTRICAL STEEL Russian patent published in 2017 - IPC C21D8/12 C22C38/60 C22C38/06 H01F1/16 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy, namely to production of sheet of textured electrical steel, used for making cores of transformers and electric generators. Steel slab including, in wt%: C: 0.04–0.12, Si: 1.5–5.0, Mn: 0.01–1.0, soluble Al: 0.010–0.040, N: 0.004–0.02, one or both of S and Se: in total 0.005–0.05, heated to temperature no less than 1,250 °C and subjected to hot rolling for producing hot-rolled sheet with thickness no less than 1.8 mm. One-, two- or multiple cold rolling is made with intermediate annealing between them for producing cold-rolled sheet with final thickness of 0.15–0.23 mm, then primary recrystallization annealing and final annealing are made. Ratio of soluble Al to N in steel slab (soluble Al/N) and final thickness d (mm) satisfy equation 4d+1.52 ≤ soluble Al/N ≤ 4d+2.32. Steel sheet in process of heating of final annealing is held at temperature of 775–875 °C for 40–200 hours, and then heated in temperature range of 875–1,050 °C at heating rate 10–60 °C/h for secondary recrystallization and purification.

EFFECT: obtaining extremely thin sheets of grain-oriented electrical steel with low losses in iron and small deviations in roll.

9 cl, 2 dwg, 4 tbl, 2 ex