Classifications

• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C14/00—Alloys based on titanium
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
  • F05C2201/00—Metals
  • F05C2201/02—Light metals
  • F05C2201/021—Aluminium
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05C—INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES
  • F05C2201/00—Metals
  • F05C2201/04—Heavy metals
  • F05C2201/043—Rare earth metals, e.g. Sc, Y

Definitions

• the invention relates to a multi-phase heat-resistant material made of an alloy based on an intermetallic compound of the type Ti3Al, in particular for use in heat engines, such as internal combustion engines, gas turbines, aircraft engines.
• thermal engines are increasingly aimed at higher outputs with the same size as possible, whereby the heat load of the individual components increases continuously, so that the materials used are increasingly demanding better heat resistance and strength.
• the service life is limited by condensed alkali and alkaline earth metal sulfates, which prevents utilization of the inherent strength potential of these materials, i.e. the operating temperature that can be achieved in terms of high heat resistance is reduced due to the limited resistance to oxidation.
• the alloying of silicon and niobium leads to the formation of a two-phase structure which has a significant improvement in the mechanical heat resistance and the creep rupture strength compared to the Ti3Al base alloy.
• dense protective oxide layers is of particular importance for the titanium aluminides, since they prevent the penetration of oxygen and nitrogen into the core matrix and thus prevent their embrittlement.
• reactive elements such as. As yttrium, hafnium, erbium and lanthanum and other rare earths or combinations of these elements can be provided.
• these oxides and nitrides are thermodynamically much more stable than those of titanium; on the other hand, these elements simultaneously increase the oxidation resistance of the specified intermetallic compounds.
• the production and processing of the high-temperature material according to the invention does not present any particular difficulties, but can be carried out by the customary methods, such as those used in such materials.
• the high-temperature material according to the invention with the addition of oxides of the aforementioned reactive elements is produced by mechanical alloying in order to obtain particularly heat-resistant intermetallic compounds in this way.
• the addition of boron (0.05 to 5 at%) or carbon or nitrogen (0.05 to 1 at%) or combinations of these elements is provided in order to further improve the mechanical properties and a to achieve fine-grained structure. This is achieved in that stable borides, carbides and nitrides or carbonitrides are formed by the additions of boron, carbon and nitrogen mentioned.
• the components can be manufactured using the following methods:
• a rod-shaped electrode with a composition according to the patent claim is melted under vacuum in molded shells by arc melting.
• the melt flows into the mold shell, the temperature of which can be between room temperature and 1200 ° C.
• the molded shells can be fixed during the casting or rotate around an axis of rotation.
• the component is heat-treated, mechanically or chemically processed and used as a turbine blade for guide and rotor blades.
• Powder metallurgical processes are alternative manufacturing processes for casting, which are used preferably when there are particularly high demands on homogeneous composition and tight tolerances with regard to the grain sizes of the structure. This process can also be used to manufacture complex-shaped components such as tubing blades or turbocharger wheels using the manufacturing technologies known for other materials. In the case of titanium aluminides, only low oxygen and nitrogen contents need to be observed during the production of the powders, which can be achieved by vacuum or protective gas atomization during powder production.
• the components made of titanium aluminides produced by these processes are preferably used for rotating components such as blades in stationary gas turbines and aircraft engines, because due to their low density (only approx. 50% of the density of nickel-based alloys) they almost halve centrifugal forces and increase the service life of rotors.
• the weight savings associated with the use also play a significant role, since the fuel consumption of the engine can be reduced.
• the low density of the material ensures that the compressor impeller responds quickly to rapid load changes.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Turbine Rotor Nozzle Sealing (AREA)
• Manufacture Of Alloys Or Alloy Compounds (AREA)

Applications Claiming Priority (2)

Publications (2)

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Family Applications (1)

Country Status (3)

Cited By (4)

Families Citing this family (3)

Citations (4)

Family Cites Families (1)

• 1992
  • 1992-05-08 DE DE19924215194 patent/DE4215194C2/de not_active Expired - Fee Related
• 1993
  • 1993-05-05 EP EP93107134A patent/EP0568951A2/fr not_active Ceased
  • 1993-05-10 JP JP10856593A patent/JPH0649568A/ja active Pending

Patent Citations (4)

Non-Patent Citations (3)

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