JPH10193087A - Manufacture of titanium-aluminum-made turbine rotor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a TiAl-made turbine rotor which precisely matches the axes of a TiAl rotor impeller excellent in heat resistance and a shaft of a steel for structural use or a heat resistant steel and the joined strength of the shaft and the rotor impeller. SOLUTION: The manufacturing method of the TiAl-made turbine rotor is executed by forming the part to be joined, of the TiAl-made turbine impeller (a) to a projecting shape and the part to be joined, of the shaft (b) to a recessing shape and inserting brazing filler metal (d) to the TiAl-made turbine impeller (a) produced with a precision casting and the rotor shaft (b) composed of the steel for structural use or the martenstic heat resistant steel. The projecting part of the TiAl-made turbine impeller (a) and the recessing part the shaft (b) part are fitted and the pressure having >=0.01kgf/mm<2> and each yield stress or lower of the shaft (b) and the rotor impeller (a), is loaded on the interface between the brazing filler metal (d) and the material to be joined. Then, the brazing is executed while heating and holding the joining interface part to the liquidus temp. or higher of the brazing filler metal (d) and the liquidus temp. + within 100 deg.C with a high frequency induction heating under inert gas atmosphere.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a TiAl turbine rotor used for a supercharger for an internal combustion engine.

[0002]

2. Description of the Related Art Up to now, a turbine impeller of a supercharger for an internal combustion engine has been provided with a superalloy In for Ni-base casting which is excellent in high-temperature strength.
A structure in which a shaft made of structural steel is joined to a turbine impeller of a precision casting such as console 713C by friction welding or electron beam welding has been used.

In recent years, ceramic rotors made of silicon nitride have been put to practical use in order to improve the heat resistance of the turbocharger turbine impeller and to improve the responsiveness of the engine by reducing inertia due to weight reduction.

However, this ceramic impeller also has the following disadvantages: 1) its toughness is poor and its wall thickness must be thicker than that of a conventional metallic rotor impeller. 2) Since thermal expansion is small, it is difficult to balance thermal expansion with surrounding parts such as a casing. There were drawbacks such as.

[0005] Therefore, as a new material that has recently replaced ceramics, the specific gravity is 3.8, which is close to that of ceramics, and the specific strength at high temperature (the value obtained by dividing the strength by the density) is Ni-base superalloy Inc.
Onel 713C or higher, and has higher toughness than ceramics and a coefficient of thermal expansion close to that of metal
(1) Intermetallic compounds have been proposed for turbine impellers (for example, JP-A-61-229901).

[0006] The turbine impeller is manufactured by precision casting or constant temperature forging, and a rotor is manufactured by joining the impeller and a structural steel shaft. This TiAl
Has a toughness not found in ceramics, but has a ductility at room temperature of about 1%. Therefore, applying frictional joining, which has been performed in the conventional joining of a Ni-base superalloy impeller and a structural steel shaft, results in a structure at the time of cooling. Residual stress is generated by the volume expansion generated when the steel for use transforms from austenite to martensite, and the TiAl cracks.Also, the carbon in the structural steel reacts with the Ti in TiAl at the joint interface to form carbides. To reduce the interfacial strength.

Therefore, in order to solve these problems,
Methods of vacuum brazing and friction joining of an austenitic material having no transformation between the TiAl impeller and the shaft as an intermediate material have been proposed (for example, Japanese Patent Application Laid-Open No. Hei 2-13318).
3).

However, in the case of vacuum brazing and the friction joining method using an austenitic material as an intermediate material, the former requires joining in a high vacuum, which requires a long time for processing, including evacuation, and is costly. Further, in the latter case, the intermediate member must be joined twice, for example, by first friction-joining the intermediate member to the shaft, and then joining the shaft joined to the intermediate member to the impeller the second time. Not only is it difficult to control the thickness after joining the materials, but also the joining cost is high. Therefore, high-frequency brazing that can be performed quickly and at low cost is conceivable.

[0009]

However, since the joining interface is flat, it is difficult to accurately align the axis of the TiAl impeller with the axis of the shaft, and there has been a problem that these are shifted and eccentric. Also, since TiAl has a high thermal conductivity,
Since heat conduction from the TiAl impeller exposed to high temperature during operation to the shaft is large, the temperature of the shaft becomes high, causing a problem that the bearing is seized. Therefore, an object of the present invention is to provide a method of manufacturing a turbine rotor made of TiAl that accurately aligns the axis of the TiAl impeller with the axis of the shaft and reduces heat conduction to the shaft.

[0010]

SUMMARY OF THE INVENTION A method for manufacturing a TiAl turbine rotor according to the present invention comprises the steps of combining a TiAl turbine impeller manufactured by precision casting with a rotor shaft made of structural steel or martensitic heat-resistant steel. 1
As shown in (a), the joined part a of the TiAl turbine impeller is made convex, and the joined part b of the shaft is made concave,
Alternatively, as shown in FIG. 1 (b), the joint a of the turbine impeller made of TiAl is made concave, and the joint b of the shaft is formed.
And the brazing material d is inserted between them, and the uneven portion of the TiAl turbine impeller and the shaft are fitted together, and the interface between the brazing material and the material to be joined is 0.01 kgf / mm ² or more and the joining temperature is , A pressure equal to or lower than the yield stress of the shaft and rotor impeller is applied, and the bonding interface is heated to a liquidus temperature equal to or higher than the liquidus temperature of the brazing material by high frequency induction heating in an inert gas or reducing gas atmosphere. ° C
It is characterized in that brazing was performed while heating and holding within.

At this time, the outer diameter D2 of the convex portion and the inner diameter D of the concave portion
1 is 0 mm <D1−D2 ≦ 1 mm, and the outer diameter D0 of the joint portion and the inner diameter D1 of the concave portion are D1 ² / D02 ² ≦
0.8, the depth H1 of the concave portion and the height H2 of the convex portion are 0 mm <H1−H2 ≦ 15 mm, and the joint portion has a cavity.

Further, the brazing material to be used is mainly composed of Ag, Cu, Ni or Ti. Further, in the combination of the brazing material to be used and the shaft, the liquidus temperature of the brazing material is changed to austenite of the shaft. It is characterized by being at a temperature or higher. In addition, the entire shaft is heated to an austenitizing temperature or higher by high-frequency induction heating, and after brazing, a cooling gas or a cooling liquid is blown onto the shaft to cool it, thereby simultaneously performing brazing and quenching of the shaft. I do.

The present invention can be applied to any turbine impeller made of TiAl.
Because it is a component that rotates at high speed, it is necessary to have excellent high-temperature strength and ductility, and also to have excellent oxidation resistance. Therefore, the typical composition of TiAl for which application of the present invention is recommended is:
It has the following composition. 1) Al: contains 31 to 35%, with the balance being substantially Ti
TiAl consisting of 2) In addition to the composition of TiAl of 1), one or more of Cr, Mn, and V are 0.2 to 4.0% in total.
Containing TiAl. 3) In addition to the composition of TiAl of 1) or 2), Nb, T
a, Ti, Al containing one or more of 0.2 to 10.0% in total from W, Re. 4) In addition to the composition of TiAl of 1) to 3), Si:
TiAl containing 0.01-1.00%. 5) In addition to the composition of TiAl of 1) to 4), Zr:
<1.0%, Fe: <1.0%, C: <0.2%, O:
<0.2%, N: <0.2% T
iAl.

Hereinafter, the present invention will be described specifically with reference to the drawings. The present invention relates to a method of manufacturing a TiAl turbine rotor in which a TiAl turbine impeller and a shaft are high-frequency brazed, and when the surface to be joined is flat, T
In order to solve the problem that the axial center between the iAl turbine impeller and the shaft is displaced and the problem that the temperature of the shaft rises excessively during use due to the good heat conduction of TiAl, the coating of the TiAl turbine impeller and the shaft is performed. The joint surfaces are made uneven, the centers of the shafts are aligned by fitting, and the dimensions of the uneven portions are changed to form a cavity in the joint portion, thereby inhibiting heat conduction and preventing an increase in the temperature of the shaft.

FIG. 1A shows a case where the surface to be joined of the TiAl turbine impeller is convex and the surface to be joined of the shaft is concave, and FIG. 1B is a case where the surface of the TiAl turbine impeller is concave. This is the case where the joint surface a is concave and the joint surface b of the shaft is convex. At this time, in order to easily perform the fitting, the diameter D2 of the convex portion and the hole diameter D1 of the concave portion are set to 0 <D1-D2.
≤ 1 mm, preferably a loose fit,
As a result, the brazing material enters the gap at the time of joining, the area of the joining portion increases, and an increase in joining strength can be expected. This difference is 0mm
In the following, shrinkage occurs, and the fitting cannot be performed easily. On the other hand, if it is 1 mm or more, the deviation of the axis between the TiAl turbine impeller and the shaft increases, which is contrary to the spirit of the present invention.

The outer diameter D0 of the shaft and the hole diameter D of the concave portion
1 and D1 ² / D0 ² ≦ 0.8, the area of the joint portion can be sufficiently secured and the strength can be secured, but D1 ² / D0 ² > 0.
If it is 8, the area of the joining portion is small, the strength is reduced, and it is not practical.

Further, the depth H1 of the concave portion and the height dimension H of the convex portion are set.
By setting 1 to 0 <H1-H2 ≦ 15 mm, FIG.
It is possible to create a cavity at the junction as shown in FIG. Since heat conduction of metal is remarkably higher than that of gas, heat conduction from the TiAl turbine impeller to the shaft is reduced by forming a cavity, and it is possible to prevent a rise in the temperature of the shaft. At this time, the shape of the bottom surface of the convex portion and the concave portion does not need to be flat.
As shown in (b), it may be conical like a drill hole.

At the time of joining, as shown in FIG. 3, a load is applied to one end of the shaft and a pressure is applied to the joining interface, so that the wettability of the interface between the brazing material and the material to be joined is improved during high-frequency brazing. Not only is it possible to prevent a decrease in the joining strength due to the formation of the joining portion, but also the wax goes around the space where the fitting is performed, which substantially increases the joining area and increases the strength. In particular, when a pressure of 0.01 kgf / mm ² or more is applied, the wettability improves, but when the surface roughness of the joint surface is large, it is desirable to increase the pressure.

However, if the welding temperature exceeds the yield stress of the shaft and the rotor impeller, plastic deformation occurs at the joint, so that the pressure needs to be equal to or less than the respective yield stress. In addition, brazing can be performed at a temperature equal to or higher than the liquidus temperature of the brazing material.However, when the temperature increases, the material to be joined and the brazing material react with each other to generate a compound at the joining interface, and the joining strength decreases. It is necessary that the temperature be equal to or higher than the liquidus temperature of the brazing material and equal to or lower than + 100 ° C. At this time, Ag,
It is possible to use a brazing material containing Cu, Ni or Ti as a main component, and it may be in the form of a foil or powder.

Furthermore, since the increase in the unwelded portion due to the deterioration of the wettability of the brazing material during heating and the brazing material due to oxidation of the surface to be joined causes a decrease in bonding strength, the TiAl turbine impeller and shaft are made of heat-resistant glass or the like. Cover, flowing an inert gas or reducing gas between the heat-resistant glass and these,
Oxidation was prevented. In particular, when the brazing material contains an active metal, it is desirable to flow a reducing gas (for example, a He gas containing 5% of hydrogen).

Investigation of the brazing time by the above-described method revealed that sufficient bonding strength was obtained in 30 seconds. In the case of a shaft having a diameter of 17 mm, the time from the start of heating was reduced. The bonding was completed in a short time of about 90 seconds until the bonding was completed.

After the joining, the shaft is reconditioned to
When performing quenching and tempering, the liquidus temperature of the brazing filler metal in the combination of the brazing filler metal and the shaft used should be set so that the joint interface does not re-melt and deteriorate due to quenching of the shaft. The temperature must be equal to or higher than the austenitizing temperature of the shaft. In practice, the brazing material at the joint after joining has a liquidus temperature slightly higher than the liquidus temperature of the brazing material itself due to the diffusion of other elements from the joined part during joining. Is applicable even if the liquidus temperature is the same as the austenitizing temperature of the shaft.

In order to harden the shaft simultaneously with brazing, as shown in FIG. 4, the entire shaft is heated by high-frequency heating, and after brazing, cooling of Ar and He gas or the like from a heat-resistant glass nozzle. This is possible by spraying a cooling liquid such as gas or water onto the shaft to rapidly cool the shaft.

The TiAl turbine impeller used in the present invention may be manufactured by either precision casting or high-temperature forging. Furthermore, the ductility of a TiAl turbine impeller can be improved by heat treatment in the range of 1200 ° C to 1350 ° C.
1000 kgf / cm in the range of 200 ° C to 1350 ° C
By applying the HIP heat treatment at a pressure of ² or more, it is possible to eliminate internal casting defects, improve reliability, and improve strength and ductility.

[0025]

The reasons for limiting the composition of the TiAl turbine impeller according to the present invention will be described below. Al: 31-35% Al combines with Ti to form intermetallic compounds TiAl and T
It is an element that produces i ₃ Al. TiAl and Ti ₃
Al single phase are brittle either, but strength is low compound, the Al is in the range of 31-35%, is as _Ti 3 Al are included a 5-30% by volume in TiAl phase, A two-phase state results in increased ductility and strength. However, when Al becomes 31% or less, Ti ₃ Al increases, or when Al becomes 35% or more, Ti ₃ Al
Decreases, the strength and ductility decrease significantly.

One, two or more of Cr, Mn, and V: 0.2 to 4.0% Cr, Mn, and V are all elements that improve the ductility of TiAl. The reason why these elements show the ductility improving effect is that the total of one or more of these elements is 0.2% or more, and if it exceeds 4%, the oxidation resistance is remarkably deteriorated and the β phase There is an inconvenience that formation occurs and the high-temperature strength decreases.

[0027] Nb, Ta, W, and Re: one or more of the total of 0.2 to 10.0% Nb, Ta, W, and Re are elements that improve the oxidation resistance of TiAl. These elements show the effect of improving oxidation resistance only when one or a combination of two or more of these elements has a resistance to oxidation.
If it is 2% or more, and if it exceeds 10%, the ductility is reduced, and the density of TiAl is increased, so that the characteristics of TiAl having a low density are disadvantageously lost.

Si: 0.01% to 1.00% Si reacts with Ti to form a silicide (Ti ₅ Si ₃ ).
Is an element that not only improves the creep characteristics of TiAl, but also improves the oxidation resistance. These effects are exhibited at 0.01% or more, and when added in excess of 1.00%, the ductility decreases.

Zr: <1.0%, Fe: <1.0%,
C: <0.2%, O: <0.2%, N: <0.2% Zr, Fe, C, O, and N are mixed in from the precision casting process and raw materials of the TiAl rotor impeller. It is an impurity element, and when these are mixed in a large amount, the ductility of TiAl is significantly reduced. Therefore, the upper limits of these elements are set to 1.0%, 1.0%, 0.2%, 0.2% and 0.2%, respectively.

[0030]

【Example】

Example 1 Table 1 shows the misalignment between the axis of a TiAl turbine impeller and the axis of a shaft of a turbine rotor joined by changing the shape of the joint. At this time, TiAl
52-3mm Ti-33.5A made of turbine impeller
1-4.8Nb-1.0Cr-0.2Si (wt%) using a precision cast material with a shaft material having an outer diameter D
0 = 17 mm, length 110 mm nickel-chromium-molybdenum steel SNC for structural steel specified in JIS G4103
M439 was used. For the brazing material, Ag-
A silver brazing foil having a composition of 35.3Cu-1.7Ti (wt%) was used.

The joining was performed by high-frequency heating as shown in FIG. First, the brazing material d was inserted into the joint interface, the upper part of the shaft was pressurized, and a pressure of 0.5 kgf / mm ² was applied to the joint interface. The brazing material used was a foil having a thickness of 0.05 mm. Further, in order to make the joining portion an inert atmosphere, the periphery of the material to be joined was covered with heat-resistant glass, and Ar gas was flowed between the material to be joined and the heat-resistant glass to seal the atmosphere.
In the high frequency induction heating, a heating coil is placed outside the heat-resistant glass and heated to 850 ° C.
After holding for 2 seconds, the power was turned off and cooling was performed.

After the joining, the shaft center of the TiAl turbine impeller and the axis of the shaft are displaced as shown in FIG. 5, the shaft is fixed and rotated, and the maximum value of the change in the outermost diameter of the turbine impeller is determined. The run-out of the core. Core runout is 3 each
It was expressed as the average of individual tests. Also, after measurement
A tempering heat treatment of AC was performed at 30 ° C. for 30 minutes to perform a torsion test of the joint. As a result, the run-out of the shaft of the turbine rotor of the present invention in which the joining surface was made uneven and fitted and joined was significantly smaller than that of the comparative example 1 in which the joining portion was flat and joined. I understand. Also, D
In the rotor of Comparative Example 3 in which 1 ² / D0 ⁰ > 0.8, a sufficient torsional rupture torque could not be obtained because the area of the joint surface was small. Further, the rotor of Comparative Example 2 has D1-D2> 1.
It is 0 mm, and it can be seen that the fitting gap between the concave and convex portions is large, and the runout of the core is large as in the case where the joint is flat.

[Table 1]

Example 2 Table 2 shows the brazing filler metal, shaft and TiAl
1 shows a combination of turbine impellers. For the shaft material, SNCM439 used in Example 1 and JISG4311
A heat resistant steel SUH11 was used for the specified marte. These were subjected to high-frequency heating in the same manner as in Example 1,
A 52 mm diameter TiAl turbine impeller manufactured by precision casting and a shaft material processed to an outer diameter D0 of 17 mm and a length of 110 mm were joined. At the joint, the shaft material is concave, D1 = 8 mm, H1 = 6 mm, and TiAl
The impeller was convex, with D2 = 7.9 mm and H2 = 1 mm.

Further, the brazing materials include silver brazes specified in JISZ3261 such as BAg-7 and 13A, and Ag-3.
A silver braze A having a composition of 5.3Cu-1.7Ti (wt%), a nickel braze BNi-3 specified in JISZ3265, and Cu-10Co-31.5Mn
(Wt%) of copper braze B and Ti-15Ni
Titanium brazing alloy C having a composition of −15 Cu (wt%) was used. The brazing material used was a foil having a thickness of 0.05 mm. At this time, the pressure at the joint is 0.5 kgf /
mm ² , the joint is heated to the temperature of the liquidus temperature of the brazing material + 50 ° C. and, after the temperature has become constant, held for 30 seconds,
The power was turned off and cooling was performed.

The joined turbine rotors were quenched and tempered under the condition as they were and under the respective conditions shown in Table 2, the joint was machined to a diameter of 16 mm, and the torsional test was performed at room temperature. Hardening / tempering is JISG4
The test was performed in the designated ranges of 103 and 4311. The turbine rotor of the present invention had a torsional rupture torque of 10 kgf · m or more after joining and quenching / tempering, and showed sufficient strength as the joining strength of the turbine rotor shaft.

However, since the rotors of Comparative Examples 1 to 3 were quenched and tempered, the liquidus temperature of the brazing material was lower than the austenitizing temperature of the shaft. As a result, the strength was remarkably reduced, and did not show sufficient strength as a turbine rotor.

[Table 2]

Example 3 In order to perform the joining and quenching of the shaft at the same time, the entire shaft was heated by high-frequency induction and quenched at the same time as brazing. The used TiAl turbine impeller, shaft material, brazing material, joint shape and joining conditions are the same as those of the fifth embodiment of the present invention. However, instead of Ar gas flowing as a shielding gas between the heat-resistant glass and the shaft when heating and holding are completed, high-pressure Ar gas is blown from the heat-resistant glass cooling gas blowing nozzle to the shaft to rapidly cool the shaft and harden. went. The joined rotor performs a torsional test of the joint at room temperature,
The hardness of the shaft was measured. The torsional breaking torque at room temperature is
The shaft showed sufficient strength of 13.7 kgf · m, and the surface hardness of the shaft showed sufficient hardening hardness with HRC55, and it was possible to perform hardening simultaneously with brazing.

Example 4 The outer diameter of the joint was obtained by using the rotor of Example 3 having a cavity in the joint of Example 1 and the rotor of Comparative Example 1 in which the joint in Example 1 was flat and had no cavity. The rotor was machined into a rotor having a final shape of D0 = 15 mm, and the bearing was induction hardened to produce a prototype turbocharger. The engine test uses a diesel engine and the engine speed is 4000r.
A 100 hr durability test was performed at pm. As a result, the bearing portion of the rotor having no cavity in Comparative Example 1 was partially discolored, indicating that the temperature increased, but no discoloration was observed in the bearing portion of the rotor having the cavity of the present invention, It was confirmed that the temperature was not increased as compared with the rotor having no cavity.

[0039]

According to the present invention, TiO having excellent heat resistance can be obtained.
It is possible to provide a method for manufacturing a TiAl turbine rotor in which the rotor impeller and the shaft of the structural steel or heat-resistant steel are precisely aligned with each other, and the joint strength between the shaft and the rotor impeller is high.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing the structure of a joint according to the present invention.

FIG. 2 is an explanatory view showing a structure of the present invention having a cavity at a joint.

FIG. 3 is an explanatory view showing a joining method according to the present invention.

FIG. 4 is an explanatory view showing that quenching and joining of a shaft are simultaneously performed in the present invention.

FIG. 5 is an explanatory diagram showing a method for measuring a deviation between the axis of the TiAl turbine impeller and the axis of the shaft in the first embodiment.

[Explanation of symbols]

 a Turbine impeller made of TiAl b Shaft C joint d Brazing material D0 Outer diameter of shaft D1 Inner diameter of concave part D2 Outer diameter of convex part H1 Depth of concave part H2 Height of convex part e High-frequency heating coil f Heat resistant glass g TiAl Turbine impeller support h Ar gas i Coolant gas and coolant spray nozzle j Load k Cavity l Rotor support

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B23K 35/24 310 B23K 35/24 310 C21D 1/76 C21D 1/76 E 9/28 9/28 A 9/50 101 9 / 50 101Z C22C 14/00 C22C 14/00 Z F01D 5/02 F01D 5/02 5/28 5/28 H05B 6/10 331 H05B 6/10 331 // B23K 103: 18 103: 24

Claims (12)

[Claims] 1. A TiAl turbine impeller manufactured by precision casting and a rotor shaft made of structural steel or martensitic heat-resistant steel are attached to a TiAl turbine impeller as shown in FIG. 1 (a). The joining part a is made convex, the joint part b of the shaft is made concave, a brazing material d is inserted between them, the convex part of the TiAl turbine impeller and the concave part of the shaft part are fitted, and the brazing material is covered with the brazing material. A pressure of 0.01 kgf / mm ² or more and a joining stress of not more than the yield stress of the shaft and the rotor impeller is applied to the interface with the joining material, and in an inert gas or reducing gas atmosphere,
A method of manufacturing a turbine rotor made of TiAl, wherein brazing is performed while heating and holding a joining interface portion at a temperature equal to or higher than the liquidus temperature of the brazing material and within the liquidus temperature + 100 ° C by high-frequency induction heating. 2. A TiAl turbine impeller manufactured by precision casting and a rotor shaft made of structural steel or martensitic heat-resistant steel are mounted on a TiAl turbine impeller as shown in FIG. 1 (b). The joint part a is made concave, the joint part b of the shaft is made convex, and a brazing material d is inserted between them. The concave part of the turbine blade made of TiAl and the convex part of the shaft part are fitted to each other. A pressure of 0.01 kgf / mm ² or more and a joining stress of not more than the yield stress of the shaft and the rotor impeller is applied to the interface with the joining material, and in an inert gas or reducing gas atmosphere,
A method of manufacturing a turbine rotor made of TiAl, wherein brazing is performed while heating and holding a joining interface portion at a temperature equal to or higher than the liquidus temperature of the brazing material and within the liquidus temperature + 100 ° C by high-frequency induction heating. 3. The method for manufacturing a TiAl turbine rotor according to claim 1, wherein an outer diameter D2 of the convex portion and an inner diameter D1 of the concave portion are 0 mm <D1-D2 ≦.
1 mm, and the outer diameter D0 of the joint portion and the inner diameter D1 of the concave portion
Wherein D1 ² / D0 ² ≦ 0.8. 4. The method of manufacturing a turbine rotor made of TiAl according to claim 1, wherein the depth H1
And the height H2 of the projection is 0 mm <H1-H2 ≦ 15 mm
Wherein a cavity is formed at the joint interface.
A method for manufacturing an Al turbine rotor. 5. The method for manufacturing a turbine rotor made of TiAl according to claim 1, wherein a brazing material mainly composed of Ag, Ni, Cu or Ti is used as a brazing material used for joining. Of manufacturing a TiAl turbine rotor. 6. The method for producing a TiAl turbine rotor according to claim 1, wherein a liquidus temperature of the brazing material is equal to or higher than an austenitizing temperature of the shaft in a combination of the brazing material and the shaft used. A method of manufacturing a turbine rotor made of TiAl. 7. The method for manufacturing a turbine rotor made of TiAl according to claim 1, wherein the entire shaft is heated to an austenitizing temperature or higher by high-frequency induction heating, and after brazing, a cooling gas or a cooling liquid is applied to the shaft. A method of manufacturing a turbine rotor made of TiAl, wherein brazing and quenching of a shaft are simultaneously performed by spraying and rapid cooling. 8. A method for manufacturing a turbine rotor made of TiAl according to claim 1, wherein the composition of the turbine impeller made of TiAl contains 31 to 35% by weight of Al and substantially the balance is made of Ti. Ti characterized by becoming
A method for manufacturing an Al turbine rotor. 9. The method of manufacturing a TiAl turbine rotor according to claim 8, wherein the composition of the TiAl turbine impeller is one or more of Cr, Mn, and V in a total of 0.2 to 4. 0% by weight of Ti
A method for manufacturing an Al turbine rotor. 10. The method for manufacturing a TiAl turbine rotor according to claim 8, wherein the composition of the TiAl turbine impeller is Nb, Ta, W, Re, and one or more of Nb, Ta, W, and Re are 0 in total. A method for producing a turbine rotor made of TiAl, characterized in that the turbine rotor comprises 0.1 to 10.0% by weight. 11. TiAl according to claim 8, wherein
The composition of the TiAl turbine impeller in the method for producing a turbine rotor made of Si is 0.01 to 1.
A method of manufacturing a turbine rotor made of TiAl, characterized in that the turbine rotor comprises 0%. 12. The TiAl turbine impeller according to claim 8, wherein the composition of the TiAl turbine impeller in the method for manufacturing a TiAl turbine rotor is Z% by weight.
r: <1.0%, Fe: <1.0%, C: <0.2%,
A method for producing a TiAl turbine rotor, wherein O: <0.2% and N: <0.2%.