METHOD OF MANUFACTURING CAST BLANK OF WEAR-RESISTANT CAST IRON FOR QUICK-WEARABLE PARTS Russian patent published in 1998 - IPC

FIELD: ferrous metallurgy. SUBSTANCE: smelting of cast iron is performed by fusing iron-carbon charge in electrical furnace while simultaneously alloying charge for specified composition. Modification is carried out using silica-barium when smelt heated in the furnace to 1400-1470 C is tapped into ladle. Smelted cast iron is composed of (in wt %): C, 2.4-4.0; Si, 0.5-1.5; Mn, 2.0-4.0; Ni, 2.0- 4.0; Cr, 8.0-12.0; molybdenum, 0.5-0.8; B, 0.1-0.3; Ba, 0.005-0.001; P, 0.02-0.01; S, 0.02-0.07; Fe, the balance. Castings are obtained by filling sand or metal mold with specified-composition cast iron melt. Castings are then cleaned, cut, and thermally treated. The latter procedure is performed as high-temperature tempering including heating to 690-710 C, maintaining this temperature for 6-7 h, and cooling first in furnace to 400 C and then in air. Metal blanks are used, for example, for replaceable parts of mineral processing equipment, grinding bodies of ball mills. EFFECT: increased strength and wear-resistance of castings and reduced their cost.