HIGH-STRENGTH COLD-ROLLED SHEET STEEL AND METHOD OF ITS PRODUCTION Russian patent published in 2014 - IPC C22C38/06 C22C38/04 C21D8/04 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy. Sheet is made of steel containing in wt %: C: 0.05-0.20%, Si: 0.10% or less, Mn: 0.2-1.7%, P: 0.10% or less, S: 0.10% or less, Al: 0.01-0.10%, N: 0.010% or less, Fe and arbitrarily impurities making the rest. Note here that [% Mn]/[% C]≥2.0, where [% Mn] is the content (wt. %) of Mn in steel, while [% C] is the content (wt. % ) of C in steel. Fraction of ferrite makes at least 90%, perlite fraction makes 1-10 while perlite interlamellar spacing does not exceed 0.5 mcm.

EFFECT: high-strength cold-rolled sheet steel of high pliability.

12 cl, 2 dwg, 3 tbl, 1 ex