A method for knocking out a foundry core confined in an internal cavity in a part at the end of a casting operation, in particular a lost-wax casting operation, includes at least a primary chemical knocking-out step. During the primary chemical knowing-out step, the part is subjected to a chemical solution to dissolve the core, in a sealed enclosure. The method further includes a secondary step of knocking out by ultrasounds in water or an aqueous solution contained in an ultrasound tank, during which the part is subjected to ultrasounds to loosen core residues from walls of the cavity.

The present disclosure generally relates to integrated core-shell investment casting molds that provide filament structures corresponding to cooling hole patterns in the surface of the turbine blade or stator vane, including in locations that are inaccessible due to the presence of protrusion patterns. The filament structures also provide a leaching pathway for the core portion after metal casting. The invention also relates to core filaments that can be used to supplement the leaching pathway, for example in a core tip portion of the mold.

A component is formed from a component material introduced into a mold assembly. The mold assembly includes a mold that has a cavity defined therein by an interior wall. The cavity receives the component material in a molten state to form the component. A multiple component core assembly is positioned with respect to the mold and has a first core component attached to a second core component at a core split line. A core connection component is attached to each of the first and second core components at the core split line, such that the first core component is held adjacent the second core component at the core split line. The core connection component is formed from a connection component material that is at least partially absorbable by the component material.

A method of method of making an airfoil includes making a refractory metal core that defines an interior of the airfoil by a tomo-lithographic process, making a mold that defines an exterior of the airfoil, inserting the refractory metal core into the mold, and pouring an airfoil material between the refractory metal core and the mold to cast the airfoil.

A method of forming a component by investment casting includes disposing at least a portion of an investment casting pin within a core. The investment casting pin includes a ceramic base pin having a perimeter and a length extending perpendicular to the perimeter and a sacrificial coating disposed about the perimeter of the ceramic base pin along at least a portion of the length of the ceramic base pin. A metal casting is formed around the core. The core and the sacrificial coating are leached with a leaching solution and the investment casting pin is removed from the metal casting.

Methods of manufacturing or repairing a turbine blade or vane are described. The airfoil portions of these turbine components are typically manufactured by casting in a ceramic mold, and a surface made up of the cast airfoil and at the least the ceramic core serves as a build surface for a subsequent process of additively manufacturing the tip portions. The build surface is created by removing a top portion of the airfoil and the core, or by placing an ultra-thin shim on top of the airfoil and the core. The overhang projected by the shim is subsequently removed. These methods are not limited to turbine engine applications, but can be applied to any metallic object that can benefit from casting and additive manufacturing processes. The present disclosure also relates to finished and intermediate products prepared by these methods.

The present disclosure generally relates to partial integrated core-shell investment casting molds that can be assembled into complete molds. Each section of the partial mold may contain both a portion of a core and portion of a shell. Each section can then be assembled into a mold for casting of a metal part. The partial integrated core-shell investment casting molds and the complete molds may be provided with filament structures corresponding to cooling hole patterns on the surface of the turbine blade or the stator vane, which provides a leaching pathway for the core portion after metal casting. The invention also relates to core filaments that can be used to supplement the leaching pathway, for example in a core tip portion of the mold.

A method of removing a core of a cast component includes providing a casting that includes a silica based ceramic core in a temperature controlled closed volume; cycling temperature between a first temperature and a second temperature within the temperature controlled closed volume that repeatedly subjects the silica based ceramic core to a beta-to-alpha cristobalite transition that induces microfractures in the silica based ceramic core; and after the cycling temperature, chemically dissolving the silica based ceramic core from the casting.

An autoclave system comprises an autoclave vessel 210, for performing a leaching operation on sacrificial ceramic cores (not shown) and a storage vessel 220 for containing caustic leaching fluid 230. Interposed in a fluid flow path between the vessel 210 and the tank 220 is a heat exchange unit 240, comprising a body 250 containing a thermal exchange medium, in the form of water 260, and first and second thermal exchange conduits represented at 270 and 280. A thermal exchange medium inlet pipe 290a and a thermal exchange medium outlet pipe 290b are provided to the body so that the medium 260 can be replenished, preferably substantially continuously, to optimize thermal transfer efficiency.

A parent bore cylinder block of an internal combustion, opposed-piston engine includes cooling passages that are formed using a 3-D printed casting core. The casting core can include portions that are ceramic. The parent bore cylinder block can include multiple cylinders, each cylinder with cooling passages and turbulence inducing features in those cooling passages, particularly surrounding the central portions of the cylinders.