A rotor blade for a gas turbine engine includes an airfoil section and a root section extending along a longitudinal direction between an upstream surface and a downstream surface. The root section further extends along a radial direction between an inner surface positioned at an inner end of the root section and an outer end coupled to the airfoil section. Moreover, the root section extends along a circumferential direction between a first side surface and a second side surface. Furthermore, the root section defines a longitudinal centerline extending along the longitudinal direction and positioned equidistant from the inner surface and the outer end in the radial direction. The root section includes a first portion formed from a composite material and a second portion formed from a metallic material, with the longitudinal centerline extending through the second portion of the root section.

A machine for generating energy by exploiting the flow of a fluid. The machine includes a first fixed or static component part or stator which defines a first cylindrical inner surface and a second outer surface. The machine further includes a second component part or rotor configured to be rotated and accommodated in the inner space confined by the first cylindrical inner surface. The first fixed or static component part or stator is configured to introduce a fluid into the inner space confined by the first inner surface through the second outer surface and first inner surface of the stator, such that the interaction between the flow of fluid introduced into the inner space and the second component part or rotor results in the second component part or rotor being rotated.

An article may include a substrate, a diffusion barrier layer formed on the substrate, and a protective layer formed on the diffusion barrier coating. The diffusion barrier layer may include iridium.

A method for the manufacture of a blisk drum is described. Disc forging for inertia welding together are provided with sacrificial material whose shape and position is selectively provided such that, on completion of the inertia welding process, integral blades can be fashioned from the sacrificial material. Other components such as buckets and balancing lands may also be provided from the sacrificial material.

A rotor blade for a gas turbine engine includes an airfoil section and a root section extending along a longitudinal direction between an upstream surface and a downstream surface. The root section further extends along a radial direction between an inner surface positioned at an inner end of the root section and an outer end coupled to the airfoil section. Moreover, the root section extends along a circumferential direction between a first side surface and a second side surface. Furthermore, the root section defines a longitudinal centerline extending along the longitudinal direction and positioned equidistant from the inner surface and the outer end in the radial direction. The root section includes a first portion formed from a composite material and a second portion formed from a metallic material, with the longitudinal centerline extending through the second portion of the root section.

A rotor blade for a gas turbine engine includes an airfoil section and a root section extending along a longitudinal direction between an upstream surface and a downstream surface. The root section further extends along a radial direction between an inner surface positioned at an inner end of the root section and an outer end coupled to the airfoil section. Moreover, the root section extends along a circumferential direction between a first side surface and a second side surface. Furthermore, the root section defines a longitudinal centerline extending along the longitudinal direction and positioned equidistant from the inner surface and the outer end in the radial direction. The root section includes a first portion formed from a composite material and a second portion formed from a metallic material, with the longitudinal centerline extending through the second portion of the root section.

A rotor blade for a gas turbine engine includes an airfoil section and a root section extending along a longitudinal direction between an upstream surface and a downstream surface. The root section further extends along a radial direction between an inner surface positioned at an inner end of the root section and an outer end coupled to the airfoil section. Moreover, the root section extends along a circumferential direction between a first side surface and a second side surface. Furthermore, the root section defines a longitudinal centerline extending along the longitudinal direction and positioned equidistant from the inner surface and the outer end in the radial direction. The root section includes a first portion formed from a composite material and a second portion formed from a metallic material, with the longitudinal centerline extending through the second portion of the root section.

A machine (100) for generating energy by exploiting the flow of a fluid, said machine comprising a first fixed or static component part or stator (101) which defines a first substantially cylindrical inner surface (1010) and a second outer surface (1011), said machine (100) further comprising a second component part or rotor (102) adapted to be rotated and accommodated in the inner space (1012) confined by said first substantially cylindrical inner surface (1010), said first fixed or static component part or stator (101) being shaped so as to allow the introduction of a fluid into the inner space (1012) confined by said first inner surface (1010) through said second outer surface (1011) and first inner surface (1010), wherein the interaction between said flow of fluid introduced into said inner space (1012) and said second component part or rotor (102) results in said second component part or rotor (102) being rotated.

A method for the manufacture of a blisk drum is described. Disc forging for inertia welding together are provided with sacrificial material whose shape and position is selectively provided such that, on completion of the inertia welding process, integral blades can be fashioned from the sacrificial material. Other components such as buckets and balancing lands may also be provided from the sacrificial material.

A small scale, high speed turbomachine is described, as well as a process for manufacturing the turbomachine. The turbomachine is manufactured by diffusion bonding stacked sheets of metal foil, each of which has been pre-formed to correspond to a cross section of the turbomachine structure. The turbomachines include rotating elements as well as static structures. Using this process, turbomachines may be manufactured with rotating elements that have outer diameters of less than four inches in size, and/or blading heights of less than 0.1 inches. The rotating elements of the turbomachines are capable of rotating at speeds in excess of 150 feet per second. In addition, cooling features may be added internally to blading to facilitate cooling in high temperature operations.