Mold for use in metal or metal alloy casting systems

A process for mixing a molten metal or metal alloy, said process comprising:

• providing a mold for containing said molten metal or metal alloy, said mold comprising a thermally and electrically conductive material;
• electromagnetically mixing said molten metal or metal alloy and thereby inducing electrical currents in a first direction in said containing means;
• wherein the improvement comprises:
• minimizing the path lengths of at least some of said currents induced in said mold by providing a mold having a stack of metal laminations separated by electrical insulating material, said electrical insulating material being oriented so that its smaller dimension is substantially transverse to said first direction so that magnetic induction losses caused by said mold are substantially reduced and the efficiency of said mixing enhanced.

An apparatus for stirring a molten metal or metal alloy, said apparatus comprising:

• a mold having inner and outer walls for containing said molten metal or metal alloy, said mold comprising a thermally and electrically conductive material;
• electromagnetic means for mixing said molten metal or metal alloy, said electromagnetic means inducing electrical currents in a first direction in said mold;
• wherein the improvement comprises:
• said thermally and electrically conductive material of said mold comprising a plurality of metal or metal alloy laminations;
• said mold further comprising means for electrically insulating said laminations from one another oriented so that the smaller dimension of said insulation means is substantially transverse to said first direction for minimizing the path lengths of at least some of said induced currents whereby magnetic induction losses caused by said mold are substantially reduced and the efficiency of said molten metal is enhanced;
• said minimizing means comprising a plurality of slits in said mold extending from said outer wall to substantially near said inner wall, said slits being of a size and location in said mold such that any coolant fluid used for cooling said molten metal or alloy flows substantially only over said outer wall without substantial penetration of said slits.

A process for mixing a molten metal or metal alloy, said process comprising:

• providing a mold having inner and outer walls for containing said molten metal or metal alloy, said mold comprising a thermally and electrically conductive material;
• electromagnetically mixing said molten metal or metal alloy and thereby inducing electrical currents in a first direction in said mold;
• wherein the improvement comprises:
• providing said thermally and electrically conductive material of said mold with a plurality of metal or metal alloy laminations;
• electrically insulating said laminations from one another oriented so that the smaller dimension of said insulating means is substantially transverse to said first direction for minimizing the path lengths of at least some of said induced currents whereby magnetic induction losses caused by said mold are substantially reduced and the efficiency of said molten metal is enchanced;
• said step of electrically insulating comprising cutting a plurality of slits in said mold extending from said outer wall to substantially near said inner wall, said slits being of a size and location in said mold such that any coolant fluid used for cooling said molten metal or alloy flows substantially only over said outer wall without substantial penetration of said slits.