ELECTRICAL STEEL SHEET, LAMINATED CORE AND ROTATING ELECTRICAL MACHINE Russian patent published in 2025 - IPC H01F41/02 H01F27/245 H02K1/04 

FIELD: electrical engineering.

SUBSTANCE: electrical steel sheet in which at least part of any or both surfaces of the main steel sheet is coated with an insulating coating having the ability to adhere. On the graph of temperature-logarithmic decrement, obtained in testing a rigid pendulum, there is an inflection point in which the absolute value of the curve decreases towards zero and then increases again in the region of decrease after the peak temperature. Temperature corresponding to the inflection point in the region of reduction after the peak temperature on the temperature-logarithmic decrement curve is defined as the temperature of the beginning of hardening. Logarithmic decrement of insulation coating in temperature range from 25 °C to 100 °C is equal to 0.3 or less. Difference between the peak temperature of the logarithmic decrement of the insulation coating and the temperature of the beginning of curing is less than 80 °C. Difference between logarithmic decrement of peak temperature and logarithmic decrement of curing start temperature is equal to 0.1 or more.

EFFECT: improving lamination accuracy, reducing noise by minimizing non-uniform hardening and achieving both the lamination coefficient and the strength of bonding of the sheet of electrical steel of the laminated core.

7 cl, 8 dwg