Patent ID: 8042268

Claim:
A method for making a gas turbine component comprising: positioning a central core to occupy a space that defines a central channel defining an internal volume of a gas turbine component; positioning an outer channel core, spaced from the central core and defining a space, at least partially, for an outer channel; forming a mold around the central core and the outer channel core, wherein an exterior wall of the outer channel core contacts the mold; adding a substrate material into the mold to form the internal volume; removing the central core and the outer channel core, thereby providing the central channel in the internal volume and an inner portion of the outer channel; forming at least one interconnect channel connecting the central channel and the outer channel inner portion; positioning into the outer channel inner portion a preform shaped to define at least an exterior portion of the outer channel; non-destructively applying an overlay material to form an outer layer that covers the internal volume and the preform; and removing the preform, thereby providing the outer channel, wherein the central channel communicates with the outer channel via the at least one interconnect channel so as to provide an optimized cooling flow through the multi-layered channels.