MANUFACTURING METHOD OF LOW ALLOYED STEEL PLATES WITH INCREASED CORROSION RESISTANCE Russian patent published in 2015 - IPC C21D8/02 C22C38/42 B21B1/26 

FIELD: metallurgy.

SUBSTANCE: section is made of steel with the following component ratio, wt %: C=0.035-0.070, Si=0.10-0.25, Mn=1.05-1.40, Cr≤0.1, Ni=0.38-0.45, Cu=0.20-0.35, Mo=0.14-0.20, Al=0.02-0.05, (Ti+V+Nb)=0.07-0.11, Fe and admixtures - rest, at that carbon equivalent is Ce≤0.42%, crack strength coefficient P_cm≤0.22%. Section austenitizing is performed to temperature 1180-1190°C for 8.5-12.0 h. Roughing-down is performed with total deformation degree 40-45%, further intermediate cooling of the rolled product is performed to 730-740°C. Accelerated cooling of the plate after finish rolling is completed at 530-560°C. Finish rolling is completed at temperature by 40°C higher than its beginning.

EFFECT: increased corrosion resistance in hydrogen and hydrosulphuric environments, and brittle fracture resistance.

2 cl, 3 tbl