METHOD FOR PRODUCING OF LOW-ALLOY STEEL SHEETS Russian patent published in 2004 - IPC

FIELD: metallurgy, in particular, manufacture of rolled products.

SUBSTANCE: method involves heating slabs; providing multiple-pass roughing and finish rolling of slabs with following reduction of thickness of rolled products in regulated temperature range. Slabs are heated to temperature of 1,150-1,190⁰C. Multiple-pass finish rolling process is performed within temperature range of from 880-900⁰C to 730-740⁰C at total reduction of at least 70%. Before roughing rolling process, slabs are additionally rolled within temperature range of from 1,200-1,280⁰C to 1,000-1,100⁰C at thickness reduction of 30-45%. Slabs subjected to rolling procedure are manufactured from low-alloy steel of the following composition, wt%: C 0.06-0.09; Si 0.40-0.55; Mn 1.45-1.65; V 0.005-0.015; Nb 0.035-0.050; Ti 0.005-0.02; Al 0.020-0.055; Cr not in the excess of 0.15; Ni not in the excess of 0.15; Cu not in the excess of 0.15; Mo not in the excess of 0.01; Ca not in the excess of 0.006; B not in the excess of 0.0008; N not in the excess of 0.010; S not in the excess of 0.006; P not in the excess of 0.015; iron the balance. Low-alloy steel sheets may be used for construction of sea platforms.

EFFECT: increased efficiency and improved quality of low-alloy steel sheets.

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