Abstract: A TiAl alloy comprising the elements C, Si, B, Al and Ti, wherein a C fraction is ?0.5 wt %, an Si fraction is 0.05-2.5 wt %, a B fraction is ?0.4 wt % and an Al fraction is 25-43 wt %, in each case in relation to the total weight of the alloy.

Abstract: A process for producing a turbine rotor (1), which has, as joining partners, a turbine wheel (2) made of TiAl and a shaft (3) produced from steel, with the following process steps: providing the turbine wheel (2); providing a solder; providing the shaft (3); and connecting the turbine wheel (2) and the shaft (3) by electron beam soldering by means of an electron beam (5).

Abstract: A flow rotor (1), in particular a turbine wheel, having a wheel core (2) and an outer part (3) which surrounds the wheel core (2) and is connected thereto. The wheel core (2) and the outer part (3) are constructed from different materials.

Abstract: A turbine wheel (1) of an exhaust-gas turbocharger (2), formed from a titanium aluminide material, having a wheel back (7) which is of closed configuration as viewed from an axial direction (A) and which has an outer contour (17), a hub (3) which extends from the wheel back (7) and which tapers along the axial direction (A), and a multiplicity of turbine blades (4) which extend from the wheel back (7) and from the hub (3) and which blades extend outward in a radial direction (R), as far as a connection region outer diameter (DAB) at least in a connection region (5). The wheel back (7) has, in an outer region (11) adjoining the connection region (5), a wheel back outer diameter (DRR) which is greater than or equal to the connection region outer diameter (DAB).

Abstract: An exhaust-gas turbocharger (1), having a shaft (2) which has an outer diameter (A2); a turbine wheel (5) which is fastened to the shaft (2); and a connecting device (8) via which the shaft (2) is fastened to the turbine wheel (5). The shaft (2) has, in the region of an end side (3), a shaft shoulder (4) with an outer diameter (A4) larger than the outer diameter (A2) of the shaft (2). The turbine wheel (5) has an external thread portion (7) integrally formed on its wheel rear side (6) The connecting device (8) has a sleeve nut (8A) which is screwed onto the external thread portion (7) and, in a process, engages behind the shaft shoulder (4) in order to brace the shaft (2) against the turbine wheel (5).

Abstract: A TiAl alloy comprising the elements C, Si, B, Al and Ti, wherein a C fraction is ?0.5 wt %, an Si fraction is 0.05-2.5 wt %, a B fraction is ?0.4 wt % and an Al fraction is 25-43 wt %, in each case in relation to the total weight of the alloy.

Abstract: A turbine wheel (1) of an exhaust-gas turbocharger (2), formed from a titanium aluminide material, having a wheel back (7) which is of closed configuration as viewed from an axial direction (A) and which has an outer contour (17), a hub (3) which extends from the wheel back (7) and which tapers along the axial direction (A), and a multiplicity of turbine blades (4) which extend from the wheel back (7) and from the hub (3) and which blades extend outward in a radial direction (R), as far as a connection region outer diameter (DAB) at least in a connection region (5). The wheel back (7) has, in an outer region (11) adjoining the connection region (5), a wheel back outer diameter (DRR) which is greater than or equal to the connection region outer diameter (DAB).

Abstract: A process for producing a turbine wheel (10), including the following process steps: casting a bar-shaped primary material (3); treating the primary material (3) in a hot isostatic pressing process (HIP process); dividing the HIP-treated primary material (3) into primary shaped parts (4 to 8); forging a blank (9) from each of the primary shaped parts (4 to 8); and creating, in particular milling, a turbine wheel (10) from the blank (9).

Abstract: A process for producing a turbine rotor (1), which has, as joining partners, a turbine wheel (2) made of TiAl and a shaft (3) produced from steel, with the following process steps: providing the turbine wheel (2); providing a solder; providing the shaft (3); and connecting the turbine wheel (2) and the shaft (3) by electron beam soldering by means of an electron beam (5).

Abstract: An exhaust-gas turbocharger (1) having a shaft (2), which has a first centric bore (4) on an end face (3), a turbine wheel (5), which has a second centric bore (7) in the wheel rear side (6) thereof, a connection piece (8), which engages into the first and second bores (4, 7); and an integral connection device (9) for connecting the shaft (2) to the turbine wheel (5), wherein the connection piece (8) is hollow in form.

Abstract: An exhaust-gas turbocharger (1), having a shaft (2) which has an outer diameter (A2); a turbine wheel (5) which is fastened to the shaft (2); and a connecting device (8) via of which the shaft (2) is fastened to the turbine wheel (5). The shaft (2) has, in the region of an end side (3), a shaft shoulder (4) with an outer diameter (A4) larger than the outer diameter (A2) of the shaft (2), The turbine wheel (5) has an external thread portion (7) integrally formed on its wheel rear side (6) The connecting device (8) has a sleeve nut (8A) which is screwed onto the external thread portion (7) and, in a process, engages behind the shaft shoulder (4) in order to brace the shaft (2) against the turbine wheel (5).

Abstract: A flow rotor (1), in particular a turbine wheel, having a wheel core (2) and an outer part (3) which surrounds the wheel core (2) and is connected thereto. The wheel core (2) and the outer part (3) are constructed from different materials.