Method for producing salt core for casting

Abstract

In a method for producing a salt core for casting formed by a molten salt made of a salt mixture containing sodium salt, first, a melt is formed by heating a salt mixture. Next, a mold for core molding is heated to a temperature higher than about 0.52×Tm and lower than about 0.7×Tm. Note that Tm represents the liquidus temperature of the salt mixture as an absolute temperature (K). Then, the melt is poured under pressure into the mold heated as described above. A salt core for casting is molded by solidifying the melt inside the mold.

1 - 3 . (canceled) 
     
     
         4 . A method for producing a salt core for casting from a molten salt made of a salt mixture containing sodium salt, the method comprising at least:
 a first step of forming a melt by heating the salt mixture;   a second step of heating a mold for core molding to a temperature higher than about 0.52×Tm and lower than about 0.7×Tm where Tm is a liquidus temperature of the salt mixture as an absolute temperature (K);   a third step of pouring the melt into the heated mold under pressure; and   a fourth step of molding a salt core for casting by solidifying the melt inside the mold.   
     
     
         5 . A method for producing a salt core for casting according to  claim 4 , wherein the mold is heated to a temperature of about 225° C. to about 250° C. 
     
     
         6 . A method for producing a salt core for casting according to  claim 4 , wherein the salt mixture has a composition in which Na+:K+=about 70 mol %:about 30 mol %, and Cl—:CO32−=about 46.2 mol %:about 53.8 mol %.