HIGH-STRENGTH SHEET OF NON-STRUCTURED ELECTRO-TECHNICAL STEEL Russian patent published in 2011 - IPC C22C38/12 C21D8/12 

FIELD: metallurgy.

SUBSTANCE: sheet is made of steel of chemical composition in wt %: C: from 0.01 to 0.05 %, Si: from 2.0 to 4.0 %, Mn: from 0.05 to 0.5 % Al: 3.0% or less, Nb: from 0.01 to 0.05 %, Fe - the rest and unavoidable impurities; also, in wt % of contents Mn and C meet condition Mn≤0.6-10×C. Share of area of re-crystallised part of steel sheet is equal to 50 % or more; yield point in tensile test is equal to 650 MPa or more, breakdown elongation is 10 % or more and losses in a core W10/400 are 70 Wt/kg or less. Average diametre of grains observed in cross section of the sheet equals to 40 mcm or less.

EFFECT: steel possesses excellent ultimate strength facilitating fabrication of motor cores or steel sheets with non-defective production of accepted items or not-reduced output at stamping.

5 cl, 5 tbl, 5 ex