The effects of magnetic induction intensity and treatment time on the properties of drying hardened sodium silicate molding sand were investgated through treating sodium silicate with magnetic separator.It is found that the optimited treatment scheme of sodium silicate in low-intensity magnetic field is magnetic induction of 0.4 T and magnetization treatment time of 30 min

where the strength of molding sand can be increased by about 37%

and the amount of sodium silicate in molding sand can be reduced by 20%. The results show that the viscosity of sodium silicate can be reduced and the dry compressive strength of sodium silicate sand can be improved by low magnetic field treatment. The sand mold made of magnetized sodium silicate should be paid more attention to moisture-proof than that of unmagnetized sodium silicate.