Process and apparatus for continuous slurry casting

A mold for use in a system for casting molten material, said mold comprising:

• first chamber means for extracting heat from said molten material, said first chamber means having means for controlling the amount of heat extracted from the molten material and the cooling rate of the molten material so as to initiate growth of primary phase particles of said material and control solidification to form a semi-solid heterogeneous slurry having a fraction solid comprising said particles sufficient to form a cast structure having a shell and a non-dendritic structure across substantially its entire cross-section, said first chamber means having inner and outer walls formed from a material having the desired thermal conductivity and an exit end;
• said controlling means comprising a plurality of spaced apart members lying in at least one circumferential plane, said members being formed from a material having substantially no thermal conductivity wherein the areas between said spaced apart members in each said plane form an effective heat transfer area for removing said heat from said molten material through said walls and wherein said controlling means comprise a plurality of said circumferential planes, each said circumferential plane containing a plurality of said spaced apart members defining said effective heat transfer area, a most upstream one said circumferential planes having the first effective heat transfer area, a most downstream one of said circumferential planes having a second effective heat transfer area wherein said first effective heat transfer area being greater than said second effective heat transfer area;
• second chamber means for casting said semi-solid slurry into an ingot having a shell and said cast structure, said second chamber means having an inlet end;
• and
• transition means between the exit end of said first chamber means and the inlet end of said second chamber means for delivering said semi-solid slurry to said casting means and for preventing said shell in said first chamber means from extending into said second chamber means and preventing said shell in said second chamber means from extending back into said first chamber means.