MANUFACTURING METHOD OF PLATES FROM MICRO-ALLOYED STEELS Russian patent published in 2012 - IPC C21D8/02 C22C38/20 B21B1/32 

FIELD: metallurgy.

SUBSTANCE: workpiece with thickness of 240-315 mm is heated during at least 3 hours to austenisation temperature of 1180-1200°C and subject to reversible rolling per odd number of passes. Rolling is performed in each pass, except two last passes with single relative swaging ≥10%, and in two last passes - ≥8%; rolling is completed at temperature of 760-780°C; after that, accelerated cooling is performed at speed of 20-30°C/sec to temperature of 500-600°C, and then optional cooling in the air is performed. Solid cast sections are obtained from steel at the following component ratio in it, wt %: C=0.03-0.05, Mn=1.4-1.6, Si=0.2-0.3, Nb=0.07-0.08, V≤0.004, Ti=0.02-0.04, Cr=0.2-0.25, Ni=0.02-0.05, Cu=0.02-0.05, Al=0.02-0.05, iron and impurities with content of each impurity element of less than 0.03% is the rest.

EFFECT: higher quality of plate.

2 cl, 2 tbl, 1 dwg, 1 ex