ELECTROTECHNICAL STEEL SHEET WITH ORIENTED STRUCTURE, ITS MANUFACTURING METHOD AND THE TRANSFORMER NOISE CHARACTERISTICS PREDICTION METHOD Russian patent published in 2018 - IPC H01F1/18 C22C38/00 C21D8/12 C23C22/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of metallurgy, in particular to the electrical steel with the oriented structure sheet, used as the transformer cores material. On its surface the sheet contains forsterite film and insulating coating. Number of the acceleration / deceleration points present in the magnetostriction velocity level dλ/dt in one period of magnetostrictive oscillations is 4. Amplitude of the change in the velocity level between adjacent points of the magnetostriction velocity level change in the magnetostriction oscillations acceleration zone or deceleration zone is 3.0×10^-4 s^-1 or less. Absolute value of the difference between the sheet surface forsterite film and the insulating coating total stress and the sheet other surface forsterite film and the insulating coating total stress is less than 0.5 MPa, and the absolute value of the difference between the sheet surface forsterite film tension and the sheet other surface forsterite film tension is 0.5 MPa or more.

EFFECT: using the disclosed sheets allows to manufacture transformers with the low noise level.

5 cl, 13 dwg, 5 tbl, 2 ex