Metal injection molded turbine rotor and metal shaft connection attachment thereto
AssigneeBorgWarner Inc.
InventorDavid M. Decker
Life of this patent
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Abstract
A rotor shaft assembly (101) of a type used in a turbocharger, manufactured by mounting a powder compact (203) of a titanium aluminide rotor (103) to a pre-formed steel shaft (107), and sintering the combination, which provides a strong metallurgical bond between the shaft (107) and rotor (103). There is provided a rotor shaft assembly (101) and an inexpensive and efficient method of its manufacture, for an assembly capable of withstanding the high forces and fluctuating temperatures within a turbocharger.
Claims10
A process for axially bonding the hub (109) of a titanium aluminide (TiAl) turbine rotor (103) to a pre-formed steel shaft (107) of a rotor shaft assembly (101) of a type used in a turbocharger for rotating about its axis (111) to drive a compressor, said process comprising:
- (a) axially mounting a preformed steel shaft (107), to the hub (209) of a compact (203) of said rotor (103), wherein said compact comprises a TiAl powder admixed with a binder, to form a mounted compact (201) optionally comprising a clearance (211) between said hub (209) of said compact (203) and said shaft (107), and
- (b) debinding and sintering said mounted compact (201),
- wherein said rotor compact (203) and said clearance (211) are selected to provide a tight fit of said hub (209) to said shaft (107) during sintering, whereby said rotor (103) and said shaft (107) are bonded by metallurgical bonding to form said rotor shaft assembly (101).
A process for axially bonding the hub (109) of a titanium aluminide (TiAl) turbine rotor (103) to a pre-formed steel shaft (107) of a rotor shaft assembly (101) of a type used in a turbocharger for rotating about its axis (111) to drive a compressor, said process comprising:
- (a) axially mounting a preformed steel shaft (107), to the hub (209) of a compact (203) of said rotor (103), wherein said compact comprises a TiAl powder admixed with a binder, to form a mounted compact (201) optionally comprising a clearance (211) between said hub (209) of said compact (203) and said shaft (107), and
- (b) debinding and sintering said mounted compact (201),
- wherein said rotor compact (203) and said clearance (211) are selected to provide a tight fit of said hub (209) to said shaft (107) during sintering, whereby said rotor (103) and said shaft (107) are bonded to form said rotor shaft assembly (101), and
- wherein said sintering is performed from about 1200° C. to about 1430° C. for a period from about 45 mm to about 2 hours.
A process for axially bonding the hub (109) of a titanium aluminide (TiAl) turbine rotor (103) to a pre-formed steel shaft (107) of a rotor shaft assembly (101) of a type used in a turbocharger for rotating about its axis (111) to drive a compressor, said process comprising:
- (a) axially mounting a preformed steel shaft (107), to the hub (209) of a compact (203) of said rotor (103), wherein said compact comprises a TiAl powder admixed with a binder, to form a mounted compact (201) optionally comprising a clearance (211) between said hub (209) of said compact (203) and said shaft (107), and
- (b) debinding and sintering said mounted compact (201),
- wherein said rotor compact (203) and said clearance (211) are selected to provide a tight fit of said hub (209) to said shaft (107) during sintering, whereby said rotor (103) and said shaft (107) are bonded to form said rotor shaft assembly (101), and
- wherein said powders have a particle size of from about 1 μm to 40 μm.
The rotor shaft assembly (101) prepared by a-process for axially bonding the hub (109) of a titanium aluminide (TiAl) turbine rotor (103) to a pre-formed steel shaft (107) of a rotor shaft assembly (101) of a type used in a turbocharger for rotating about its axis (111) to drive a compressor, said process comprising:
- (a) axially mounting a preformed steel shaft (107), to the hub (209) of a compact (203) of said rotor (103), wherein said compact comprises a TiAl powder admixed with a binder, to form a mounted compact (201) optionally comprising a clearance (211) between said hub (209) of said compact (203) and said shaft (107), and
- (b) debinding and sintering said mounted compact (201),
- wherein said rotor compact (203) and said clearance (211) are selected to provide a tight fit of said hub (209) to said shaft (107) during sintering, whereby said rotor (103) and said shaft (107) are bonded to form said rotor shaft assembly (101),
- said rotor shaft assembly (101) further comprising one or more cavities (119) disposed between the proximal end (113) of said shaft (107) and said hub (109).
Dependencies are inferred from the claim text.