Preformed ceramic seed well for single crystal starter seed

Abstract

A method of creating an article from investment casting includes forming a ceramic seed well, heating the ceramic seed well to form a hardened ceramic seed well, attaching a meltable pattern to the hardened ceramic seed well, coating the hardened ceramic seed well and the meltable pattern with hardenable ceramic material, heating the hardenable ceramic material to melt the meltable pattern, removing the meltable pattern from the hardenable ceramic material, firing the hardenable ceramic material to form a ceramic mold having a cavity, placing a seed within the hardened ceramic seed well, and pouring molten metal into the hardened ceramic seed well and the cavity. The cavity of the ceramic mold is in communication with the hardened ceramic seed well.

1 . A method of casting an article, the method comprising:
 forming a ceramic seed well;   heating the ceramic seed well to form a hardened ceramic seed well;   attaching a meltable pattern to the hardened ceramic seed well;   coating the hardened ceramic seed well and the meltable pattern with hardenable ceramic material;   heating the hardenable ceramic material to melt the meltable pattern;   removing the meltable pattern from the hardenable ceramic material;   firing the hardenable ceramic material to form a ceramic mold having a cavity, wherein the cavity is in communication with the hardened ceramic seed well;   placing a seed within the hardened ceramic seed well; and   pouring molten metal into the hardened ceramic seed well and the cavity.   
     
     
         2 . The method of  claim 1 , and further comprising attaching the meltable pattern to the hardened ceramic seed well using a gating. 
     
     
         3 . The method of  claim 1 , wherein the ceramic seed well is formed from one of the group consisting of: extrusion processing, injection processing, and slip cast processing. 
     
     
         4 . The method of  claim 1 , wherein the meltable pattern is formed from wax. 
     
     
         5 . The method of  claim 1 , and further comprising maintaining the hardened ceramic seed well and the ceramic mold at a temperature higher than a temperature of the molten metal for a predetermined amount of time. 
     
     
         6 . The method of  claim 1 , wherein coating the hardened ceramic seed well and the meltable pattern with hardenable ceramic material comprises coating the hardened ceramic seed well and the meltable pattern with a plurality of layers of hardenable ceramic material. 
     
     
         7 . The method of  claim 1 , wherein placing the seed within the hardened ceramic seed well comprises utilizing a seed having selected primary and secondary orientations. 
     
     
         8 . The method of  claim 1 , wherein the hardened ceramic seed well has a height greater than a height of the seed. 
     
     
         9 . The method of  claim 1 , and further comprising positioning the hardened ceramic seed well on a chill plate. 
     
     
         10 . The method of  claim 1 , wherein attaching the meltable pattern to the hardened ceramic seed well comprises attaching the meltable pattern to a wax plug positioned within the hardened ceramic seed well. 
     
     
         11 . A seed well formed by the steps comprising:
 positioning a meltable plug within a ceramic seed well preform;   coating the preform with a hardenable ceramic material;   removing the plug from within the perform;   firing the preform and the hardenable ceramic material.   
     
     
         12 . The seed well of  claim 11 , wherein the preform is formed from one of the group consisting of: extrusion processing, injection processing, and slip cast processing. 
     
     
         13 . The seed well of  claim 11 , wherein the meltable plug is formed of wax. 
     
     
         14 . The seed well of  claim 11 , wherein the preform has interior dimensions defined by a plurality of connected walls, and wherein the meltable plug conforms to the interior dimensions of the preform. 
     
     
         15 . An investment casting process comprising:
 attaching a first wax pattern to a first preformed seed well;   coating the first wax pattern and the first preformed seed well with at least one layer of ceramic material to form a first ceramic mold;   heating the first ceramic mold to melt and remove the first wax pattern;   firing the first ceramic mold to form a first hardened ceramic shell;   placing a first seed within the first preformed seed well; and   pouring molten metal into the first hardened ceramic shell and the first preformed seed well.   
     
     
         16 . The process of  claim 15 , wherein heating the ceramic mold to form a hardened ceramic shell comprises positioning the ceramic mold within a furnace. 
     
     
         17 . The process of  claim 15 , and further comprising positioning the ceramic mold on a chill plate. 
     
     
         18 . The process of  claim 15 , wherein the preformed seed well is foamed from one of the group consisting of: extrusion processing, injection processing, and slip cast processing. 
     
     
         19 . The process of  claim 15 , wherein attaching the wax pattern to the preformed seed well comprises attaching the wax pattern to a wax plug positioned within an interior area of the preformed seed well. 
     
     
         20 . The process of  claim 15 , wherein pouring molten metal into the preformed seed well comprises pouring the molten metal over the seed. 
     
     
         21 . The process of  claim 15 , wherein placing the seed within the preformed seed well comprises utilizing a seed having selected primary and secondary orientations. 
     
     
         22 . The process of  claim 15 , wherein the preformed seed well has a height greater than a height of the seed. 
     
     
         23 . The process of  claim 15 , wherein attaching the wax pattern to the preformed, ceramic seed well comprises attaching a wax gating of the wax pattern to the preformed seed well. 
     
     
         24 . The process of  claim 15 , wherein the preformed seed well is formed of a material selected from the group consisting of: ceramic, metal, and composite material. 
     
     
         25 . The process of  claim 15 , and further comprising:
 attaching at least a second wax pattern to a second preformed seed well;   coating the second wax pattern and the second preformed seed well with at least one layer of ceramic material to form a second ceramic mold;   heating the second ceramic mold to melt and remove the second wax pattern;   firing the second ceramic mold to form a second hardened ceramic shell;   placing a second seed within the second preformed seed well; and   pouring molten metal into the second hardened ceramic shell and the second preformed seed well;   wherein attaching the second wax pattern, coating the second wax pattern and the second preformed seed well to form a second ceramic mold, heating the second ceramic mold to melt and remove the second wax pattern, firing the second ceramic mold to form a second hardened ceramic shell, placing a second seed within the second preformed seed well, and pouring molten metal into the second hardened ceramic shell and the second preformed seed well occur simultaneously with attaching the first wax pattern, coating the first wax pattern and the first preformed seed well to form a first ceramic mold, heating the first ceramic mold to melt and remove the first wax pattern, firing the first ceramic mold to form a first hardened ceramic shell, placing a first seed within the first preformed seed well, and pouring molten metal into the first hardened ceramic shell and the first preformed seed well, respectively.   
     
     
         26 . The process of  claim 15 , wherein multiple wax patterns are attached to multiple preformed seed wells.