Abstract: An automatic ring valve 10 comprising a valve seat 12 provided with a plurality of gas flow passages 14 arranged according to at least one annular row, at least a shutter 18 comprising at least one ring-shaped portion for selectively closing and opening the gas flow passages 14, wherein said ring-shaped portion of the shutter 18 comprises a fiber-reinforced matrix 40, at least one contrasting member for contrasting an opening movement of ring-shaped portion of the shutter 18, wherein said ring-shaped portion of the shutter 18 comprises a structural core 18A made by said fiber-reinforced matrix 40, and wherein at least a portion of said structural core 18A is covered by at least one primary layer 18B, designed to improve fracture and/or impact and/or wear resistance of said ring-shaped portion.

Abstract: A sector for the assembly of a stage of a turbine comprises a central and a peripheral portion; a plurality of blades attached between the central and the peripheral portions; a first and a second side opposite to each other, the first side is configured to join with the second side of another sector, the first side is provided with a first connecting portion and the second side is provided with a second connecting portion configured to mate with a first connecting portion of a first side of another sector.

Abstract: A method for manufacturing a machine component made of metal-based material is described. The method comprises the steps of: providing a powder blend comprising at least one metal-containing powder material and at least one strengthening dispersor in powder form, wherein the strengthening dispersor in powder form has an average grain size less than an average grain size of the metal-containing powder material; and forming the machine component by an additive manufacturing process using the powder blend.

Abstract: An automatic ring valve comprising a valve seat provided with a plurality of gas flow passages arranged according to at least one annular row, at least a shutter comprising at least one ring-shaped portion for selectively closing and opening the gas flow passages, wherein the ring-shaped portion of the shutter comprises a fiber-reinforced matrix, at least one contrasting member for contrasting an opening movement of ring-shaped portion of the shutter, wherein the ring-shaped portion of the shutter comprises continuous fibers, at least some of the fibers developing for at least 360° of the annular development of the ring-shaped portion.

Abstract: A blade of a turbomachine comprises an airfoil portion; the airfoil portion extends longitudinally; the airfoil portion is defined laterally by an external surface; the airfoil portion has a 3D and twisted shape and has an internal cavity; the blade is in a single piece. Furthermore, the blade is designed for a rotor or stator array; the rotor or stator defines a radial direction and an axial direction; the external surface of the airfoil portion has a leading edge and a trailing edge; the leading edge and/or the trailing edge shifts backward or forward in the axial direction moving in the radial direction; the internal cavity extends along substantially the whole longitudinal length of the airfoil portion. Additive manufacturing is particularly effective and advantageous for such blade.

Abstract: A method of manufacturing a turbo-machine impeller, which includes a hub and a plurality of blades, using powder material in an additive-manufacturing process. The method includes: applying energy to the powder material by way of a high energy source, and solidifying the powder material. At least one bulky portion of the hub is irradiated such that the powder material solidifies in a lattice structure surrounded by an outer solid skin structure enclosing the lattice structure.

Abstract: A hollow blade for a turbomachine comprises an airfoil portion; the airfoil portion extends longitudinally for a length; the airfoil portion is defined laterally by an external surface; the airfoil portion has at least one internal cavity extending along said length and defined laterally by an internal surface; the airfoil portion has a set of channels extending from the external surface to the internal surface; the openings of said channels on said external surface are aligned along a curved line that reflects an isobar on said external surface.

Abstract: The method is used for manufacturing a turbomachine blade that comprises an airfoil portion and is divided into two parts at an intermediate region of the airfoil portion; each of the two parts of the airfoil portion is obtained by additive manufacturing; the two parts are joined by brazing.