TWO-LAYER CORROSION-RESISTANT STEEL Russian patent published in 2003 - IPC

FIELD: metallurgy of complex-alloy steels, two-layer corrosion-resistant steels in particular; manufacture of heat-exchange apparatus. SUBSTANCE: proposed steel is resistant to corrosion in flow of molten metal agent on base of lead or lead and bismuth alloy and to corrosion cracking of water-and-vapor medium at temperature of 500 C. Proposed steel consisting of main and clad layers includes the following components, mass-%: carbon, 0.005- 0/0.04; silicon, 2.20-2.80; manganese, 0.50-1.00; chromium, 14.0-25.5; nickel, 10.5-12.5; molybdenum, 0.8-1.2; titanium, 0.08-0.20 and the remainder being iron which are included in main layer; clad layer contains the following components, mass-%: carbon, 0.005-0.03;silicon, 0.05-0.35; manganese, 1.30-1.17; chromium, 20.0-22.0; nickel, 31.5- 33.0; molybdenum, 3.0-4.0; titanium, 0.05-0.50; copper, 0.01-0.15; niobium, 0.90-1.20 and the remainder being iron at (Nb+2Ti)/C≥35; thickness of clad layer ranges from 0.20 to 0.50 of total thickness of steel. EFFECT: enhanced corrosion resistance of steel. 4 tbl