GB547708A - Method of producing cast iron and compositions therefor - Google Patents

Abstract

547,708. Treating cast-iron; alloys. ELECTRO METALLURGICAL CO. Dec. 4, 1940, No. 17264. Convention date, Feb. 6, 1940. [Classes 72 and 82 (i)] To decrease the sensitivity of cast iron to variations in the rate of cooling during casting, a composition containing 25-85 per cent. of silicon, less than 65 of iron, either vanadium or titanium or both up to a total of 1-25 and 1-16 of calcium is added to a molten cast iron, the amount used being such as to increase the silicon content of the iron by about 0.05 to 1 per cent. The composition may also contain 1-25 per cent. of .manganese, part of the calcium, preferably less than half, may be replaced by one or more of the metals barium, strontium, magnesium and beryllium and a minor part of the titanium by cerium or thorium. In one method of making the cast iron, an iron containing less silicon than is desired is produced in a cupola and there are added shortly before casting, ferrosilicon and, simultaneously and in intimate association therewith, vanadium and calcium in an amount not exceeding 25 per cent. of the total addition of silicon, vanadium and calcium. Alloyed cast iron containing additions such as chromium. nickel and molybdenum may be similarly treated, and one or other of these elements may be added to the composition set out above. Specification 525,706 is referred to.