STEEL FOR SHAPED CASTINGS Russian patent published in 2002 - IPC

FIELD: metallurgy, particularly, compositions of high-strength steels for shaped castings. SUBSTANCE: steel has components in the following ratio, wt.%: carbon, 0.16-0.22; silicon, 0.15-0.30; manganese, 0.50-1.00; chromium, 0.4-0.70; nickel, 3.20-3.80; copper, 1.50-2.00; molybdenum, 0.25-0.35; vanadium, 0.02-0.10; aluminum, 0.02-0.05; calcium, 0.05-0.08; cerium, 0.02-0.05; lanthanum, 0.01-0.03; praseodymium, 0.003-0.010; zirconium, 0.005-0.100; iron, the balance. Total content of nickel and copper must be not less 5%. Proposed steel is used in manufacture of parts of equipment of transport-crane ships, sea self-propelled crane, turbine locomotive ships floating drilling units and other sea and land machines operated at low temperatures down to minus 50 C. EFFECT: high-strength steel possessing high hardenability ensuring uniform level of mechanical properties in thicknesses up to 500 mm; improved casting properties. 2 tbl