Casting with reusable precision, motion-controlled, withdrawable cores

Abstract

A method of manufacturing includes providing a casting assembly, providing a material having solid, transition, and liquid phases, heating the material to form the liquid phase, supplying the material to the casting assembly, cooling the material, monitoring the solidification of the material from the liquid phase through the transition phase, and moving one of the casting mold or the reusable core in a first direction relative to the other when a substantial portion of the reusable core contacts the transition phase. The casting assembly comprises a casting mold and a reusable core inserted within the casting mold.

1 . A method of manufacturing includes:
 providing a casting assembly comprising:
 a casting mold; and 
 a reusable core inserted within the casting mold; 
   providing a material that has a solidus temperature and a liquidus temperature, wherein the material has a solid phase at a temperature less than or equal to the solidus temperature, a transition phase at a temperature between the solidus and liquidus temperatures, and a liquid phase at a temperature greater than or equal to the liquidus temperature;   heating the material to form the liquid phase;   supplying the material to the casting assembly;   cooling the material;   monitoring a solidification of the material from the liquid phase through the transition phase; and   moving at least one of the casting mold and the reusable core in a first direction relative to the other when a substantial portion of the reusable core contacts the material in the transition phase.   
     
     
         2 . The method of  claim 1 , wherein the reusable core moves relative to the casting mold. 
     
     
         3 . The method of  claim 2  and further including:
 removing the reusable core from the casting mold, wherein a viscosity of the material surrounding the reusable core at a time immediately preceding the removal of the core is sufficient to form one or more hollow cavities within the material. 
 
     
     
         4 . The method of  claim 3  and further including:
 heating the casting assembly during the removal of the core to reduce a rate of solidification of the material. 
 
     
     
         5 . The method of  claim 2 , wherein:
 the reusable core comprises:
 a first structure that extends into the casting mold along a central axis; and 
 a second structure attached to the first structure such that the second structure is movable relative to the first structure in a direction substantially perpendicular to the central axis. 
   
     
     
         6 . The method of  claim 5 , wherein:
 the reusable core further comprises:
 a protrusion extending from the second structure configured to form a hollow cavity within the material, wherein a distal end of the protrusion is tapered. 
   
     
     
         7 . The method of  claim 1 , wherein the casting mold moves relative to the reusable core, and wherein during the solidification of the material, a substantial portion of the reusable core is immersed in the transition phase. 
     
     
         8 . The method of  claim 7 , wherein the casting mold moves from a first zone having a first temperature sufficient to form the liquid phase to a second zone having a second temperature sufficient to form the solid phase. 
     
     
         9 . The method of  claim 7 , wherein:
 the casting assembly further comprises:
 a plate forming an end of the casting mold configured to cool the material. 
   
     
     
         10 . The method of  claim 9  and further including:
 forming a unidirectional crystalline structure within the material. 
 
     
     
         11 . The method of  claim 7  and further including:
 forming a passage extending through at least a portion of the material, wherein the passage is formed by the relative movement of the casting mold to the reusable core. 
 
     
     
         12 . The method of  claim 7 , wherein:
 the reusable core comprises:
 a shaft extending in the casting mold along a central axis; 
 a plate having a first face affixed to the shaft and a second face opposite the first face; and 
 a plurality of protrusions extending from the second face, each protrusion having a tapered distal end. 
   
     
     
         13 . The method of  claim 7 , wherein:
 the reusable core comprises:
 a hollow shaft extending in the casting mold along a central axis; 
 a plurality of spokes affixed to an outer surface of the hollow shaft that extend outward from and generally perpendicular to the axis; and 
 a volute affixed to the outer surface of the hollow shaft and the plurality of spokes, wherein the volute extends in a circumferential direction about the axis. 
   
     
     
         14 . The method of  claim 7  and further including:
 moving the reusable core in a second direction relative to the casting mold, wherein the second direction is different from the first direction. 
 
     
     
         15 . The method of  claim 14 , wherein the second direction is substantially perpendicular to the first direction. 
     
     
         16 . The method of  claim 15  and further including:
 forming a first plurality of cavities and a second plurality of cavities within the material, wherein the second plurality of cavities are offset from the first plurality of cavities. 
 
     
     
         17 . The method of  claim 7 , wherein the material is periodically supplied to the casting assembly. 
     
     
         18 . A method of manufacturing a die-cast component includes:
 providing a casting assembly comprising:
 a permanent casting mold having first and second halves that mate along mating surfaces; and 
 a core plate mounted relative to the permanent casting mold, wherein the core plate defines a plurality of passages extending therethrough; 
   providing a material that has a solidus temperature and a liquidus temperature, wherein the material has a solid phase at a temperature less than or equal to the solidus temperature, a transition phase at a temperature between the solidus and liquidus temperatures, and a liquid phase at a temperature greater than or equal to the liquidus temperature;   heating the material to form the liquid phase;   supplying the material to the casting assembly through the plurality of passages of the core plate; and   controlling the solidification of the material such that the core plate is positioned substantially within the transition phase.   
     
     
         19 . The method of  claim 18  and further including:
 oscillating the core plate about the axis to form porosity within the material.