Methods for casting a component having a readily removable casting core

Abstract

A method is provided for casting a component. Accordingly, a casting core is provided within a cavity of a component mold. The casting core defines an inner component shape and includes a core wall. The core wall defines a core outer surface and a core inner surface disposed opposite the core outer surface. The core inner surface defines a core cavity. The casting core also includes a removal facilitation feature. The component is cast within the cavity of the component mold with the casting core positioned therein. The cast component is removed from the component mold and the casting core is removed from the cast component.

What is claimed: 
     
         1 . A method for casting a component, the method comprising:
 providing a casting core within a cavity of a component mold, wherein the cavity of the component mold defines an outer component shape and the casting core defines an inner component shape, the casting core comprising a core wall, the core wall defining a core outer surface and a core inner surface disposed opposite the core outer surface, wherein the core inner surface defines a core cavity, and wherein the casting core includes a removal facilitation feature;   casting the cast component within the cavity of the component mold with the casting core positioned therein;   removing the cast component from the component mold, with the casting core positioned internally within the component; and   removing the casting core from the cast component,   wherein the casting core, the component mold, or both are formed by an additive manufacturing process.   
     
     
         2 . The method of  claim 1 , wherein the core wall comprises a plurality of core layers. 
     
     
         3 . The method of  claim 1 , wherein the removal facilitation feature comprises the core wall having a core wall thickness of 0.1 mm to 5 mm. 
     
     
         4 . The method of  claim 1 , wherein the casting core is formed by an additive manufacturing process. 
     
     
         5 . The method of  claim 1 , wherein the component mold is formed by an additive manufacturing process simultaneously with forming the casting core. 
     
     
         6 . The method of  claim 1 , wherein the removal facilitation feature comprises:
 a support web contained within the core cavity and coupled to the core inner surface.   
     
     
         7 . The method of  claim 6 , wherein the support web is a single structural member with a first support end coupled to a first inner surface attachment location and a second support end coupled to a second inner surface attachment location. 
     
     
         8 . The method of  claim 6 , wherein the support web comprises:
 a plurality of support members each having a first support end coupled to a first inner surface attachment location and a second support end coupled to a second inner surface attachment location.   
     
     
         9 . The method of  claim 6 , wherein the support web is a ceramic foam or a metallic foam. 
     
     
         10 . The method of  claim 6 , wherein the casting core and the support web are formed simultaneously by an additive manufacturing process. 
     
     
         11 . The method of  claim 10 , wherein the support web comprises:
 a plurality of support members each having a first support end coupled to a first inner surface attachment location and a second support end coupled to a second inner surface attachment location, the plurality of support members forming a lattice structure spanning the core cavity.   
     
     
         12 . The method of  claim 6 , further comprising:
 forming the core wall, the core outer surface, and the core inner surface; and   introducing an expanding foam into the core cavity.   
     
     
         13 . The method of  claim 6 , wherein the cast component is a turbine engine component. 
     
     
         14 . The method of  claim 1 , wherein the removal facilitation feature comprises:
 a first core material having a thickness of 0.1 mm to 5 mm; and   a second core material contained within the core cavity, wherein the second core material leaches at a faster rate than the first core material.   
     
     
         15 . The method of  claim 14 , further comprising:
 forming a sub-core comprising the second core material;   securing the sub-core within a core mold having a core mold inner face that is the negative of a core outer shape;   introducing the first core material into the core mold to form the core outer shape; and   removing the casting core from the core mold.   
     
     
         16 . The method of  claim 15 , further comprising:
 inserting an injection apparatus into a core mold having a core mold inner face that is the negative of a casting core outer shape;   depositing a layer of the first core material on the core mold inner face;   depositing additional layers of the first core material until a core wall having a thickness of 0.1 mm to 5 mm is established;   introducing the second core material into the cavity; and   removing the casting core from the core mold.   
     
     
         17 . A method for casting a component, the method comprising:
 providing a casting core within a cavity of a component mold, wherein the cavity of the component mold defines an outer component shape and the casting core defines an inner component shape, the casting core comprising a core wall, the core wall defining a core outer surface and a core inner surface disposed opposite the core outer surface, wherein the core inner surface defines a core cavity, and wherein the casting core includes a removal facilitation feature;   casting the cast component within the cavity of the component mold with the casting core positioned therein;   removing the cast component from the component mold, with the casting core positioned internally within the component; and   removing the casting core from the cast component,   wherein the casting core is formed by a core-formation method comprising:
 forming a sub-core comprising a sub-core material; 
 securing the sub-core within a core mold, wherein the core mold is formed with a core mold inner face being the negative of a core outer shape; 
 introducing a core material into the core mold to form the core wall; 
 removing the casting core from the core mold; and 
 leaching the sub-core from the casting core. 
   
     
     
         18 . The method of  claim 17 , wherein the core wall comprises a plurality of core layers. 
     
     
         19 . The method of  claim 17 , wherein a support web is contained within the core cavity and coupled to the core inner surface. 
     
     
         20 . The method of  claim 17 , wherein the cast component is a turbine engine component.