Ceramic casting core and method
View Patent ↗A ceramic core for use in casting an article such as for example an airfoil, wherein the ceramic core has a pocket located at or near a region of the core that is otherwise associated with occurrence of a localized casting defect in the cast article. A covering is disposed on the core to cover the pocket and provide core outer surface features.
1. A method of casting a metallic article, comprising placing a ceramic core in a refractory mold wherein the core includes a pocket located proximate a region of the core that is otherwise associated with occurrence of a localized casting defect in the metallic article and having a covering on said core to cover the pocket, introducing molten metallic material in the mold about the core, solidifying the molten metallic material in the mold to form a cast metallic article, and removing the core from the cast metallic article.
2. The method of claim 1 wherein some molten metallic material leaks into and solidifies in the pocket.
3. A method of casting a single crystal superalloy airfoil, comprising placing a ceramic core in a refractory mold wherein the core includes a machined or molded pocket located proximate a region of the core that is otherwise associated with occurrence of a localized casting defect in the airfoil and having a covering on said core to close off an open outer side of the pocket, introducing molten superalloy in the mold about the core, solidifying the superalloy to produce a single crystal cast airfoil in the mold, and removing the core from the cast airfoil.