CASTING SAND CORES AND EXPANSION CONTROL METHODS THEREFOR

摘要

Thermal expansion of sand cores and the formation of vein defects during metal casting operations can be substantially eliminated, with substantially reduced costs, by using an anti-veining material comprising less than about 4% by weight of a lithia-containing material, and at least about 1% by weight of ferric oxide (Fe2O3), said anti-veining material preferably comprising about 1% to about 3.5% by weight of a lithia-containing material and about 1% by weight of ferric oxide.