| abstract |
A first-stage turbine that is adapted for receiving high energy air directly from a combustion chamber in a gas turbine engine auxiliary power unit includes a disk formed from a first alloy and having an outer surface, and a unitary blade wheel formed from a second alloy that is different than the first alloy. The unitary blade wheel includes an annular member having an inner surface that is joined to the disk, and blades that are integrally formed with the annular member. |