Patent ID: 8683689

Claim:
A method for manufacturing a hollow blade for a turbomachine, comprising a root and an airfoil, said method comprising: producing at least a first external primary part having a final geometry and comprising a first portion having a root part and a second portion, the producing comprising providing the first primary part having an initial geometry of a blank, finish forging the first primary part using a press thereby forming a protuberance on the first primary part, and removing the protuberance to form the first external primary part having the final geometry, the finish forging including at least two subsequent and complementary forging steps for the first portion and then the second portion of the first primary part using at least a first finish die during a first of the two subsequent and complementary forging steps, the first finish die being composed of a single piece and comprising a first part complementary to the first portion of the first primary part and a second part complementary to the initial geometry of the blank, and a second finish die during a second of the two subsequent and complementary forging steps, the second finish die corresponding to the final geometry of the first external primary part; and diffusion bonding the first external primary part and a second external primary part to make a blade preform, the blade preform including an airfoil portion and a root portion.