Abstract: The purpose of the present invention is to provide high manganese cast iron containing spheroidal vanadium carbide and method for making which is nonmagnetic as well as superior mechanical properties such as wear-resistance and toughness, and further does not require a water toughing heat treatment which has been needed when nonmagnetic high manganese steel (high manganese cast steel) is obtained by crystallized spheroidal vanadium in austenite matrix, and the high manganese cast iron containing spheroidal vanadium carbide is comprised of C 1.5˜4.0 weight %, V 6˜15 weight %, Si 0.2˜4.0 weight %, Mn 10˜18 weight %, Mg 0.01˜0.1 weight %, remaining iron (Fe) and inevitable impurities, spheroidal vanadium carbide is crystallized within a structure.

Abstract: A system for preparing a self-hardening casting mold including a mass of sand which contains an organic binder and which has a pattern-contact layer having a surface for contact with a pattern disposed in a flask. The pattern defines a cavity into which a melt is poured to produce a cast product. The mold further includes a mass of ceramic balls placed on the pattern-contact layer of the sand mass. The system includes a temperature adjusting device for regulating the temperature of the mass of ceramic balls prior to introduction thereof into the flask, so as to control the hardening rate of mass of sand in the flask, a separating device operable on a mixture of sand and ceramic balls obtained from the mold after the cast product is produced by the mold with the pattern removed. The separating device separates the ceramic ball from the sand, and supplies the ceramic balls to the temperature adjusting device.