PRODUCTION OF THICK-SHEET ROLLED STOCK FOR SHIP BUILDING Russian patent published in 2014 - IPC C21D8/02 C21D9/46 C22C38/38 B21B1/26 

FIELD: metallurgy.

SUBSTANCE: austenitizing of the workpiece is performed at not over 1170°C to rough said workpiece to depth of intermediate blank defined by the relationship H=109+2·(h-33)±15 mm, where h is produced rolled stock depth. Then, intermediate blank is cooled to finish at temperature of finishing end temperature not lower than 730°C. Produced rolled sheet is cooled at higher rate to 470-600°C, then cooling is decelerated to not over 160°C. After decelerated cooling of rolled sheet, tempering is performed to 550-700°C. Note here that said blank is made from steel containing the following components, in wt. %: C<0.12, Si 0.15-0.35, Mn 1.00-1.50, V+Nb+Ti<0.20, Mo+Cr<0.40, (Cu+Ni) 0.15-0.50, iron and unavoidable impurities making the rest with content of every impurity less than 0.03.

EFFECT: higher strength of rolled stock to ship 12-50 mm deep steel hardness at sufficient ductility.

3 cl