JP3106196B1 - Method for producing TiAl-Ti based alloy sintered joint - Google Patents

Abstract

Abstract: PROBLEM TO BE SOLVED: To suppress the coarsening of crystal grains of a TiAl alloy, for example, when manufacturing a TiAl alloy, for example, a sintered body having an umbrella portion and a shaft portion, such as an engine valve, by pulse current pressurization. , Suppressing the generation of vacancies and obtaining a dense structure throughout. In addition, a TiAl alloy is used for the part that receives high-temperature heat, and a titanium-based alloy with high toughness that is integrated into a part is used.
Improve the properties of iAl alloy, reduce costs and obtain high quality materials. SOLUTION: Ti _1-x Al _x (0.39 ≦ x ≦ 0.
59, x: atomic fraction), and simultaneously sintering a mixed powder or alloy powder or a sintering powder containing these as a main component, and a Ti-based alloy powder or a Ti-based alloy ingot other than the above. Join. 1000 to 1300 if necessary
A method for producing a TiAl-Ti based alloy sintered joined body, comprising extruding a TiAl alloy portion at a temperature of ° C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mixed powder or alloy powder of Ti and Al, a sintering powder containing these as a main component, and a Ti-based alloy powder or a Ti-based alloy ingot (cast,
Which are subjected to processing such as rolling), and are simultaneously sintered under current pressure and joined together, and further extruded to form Ti
By forming an Al-Ti based alloy sintered joint, it has a dense structure without voids, and is excellent in high-temperature corrosion resistance and high-temperature specific strength.
The present invention relates to a pressure sintering method suitable for composite pipes, rocker arms, and the like.

[0002]

2. Description of the Related Art TiAl intermetallic compounds (alloys) are excellent in high-temperature corrosion resistance and high-temperature specific strength, and are being used and developed as lightening materials for mechanical structural parts exposed to high temperatures. Since TiAl alloys are not only lightweight but also have such excellent properties, their use in automobile engine valves, turbine blades, rocker arms, composite pipes, etc., which are particularly exposed to high-temperature exhaust gas, has been studied. I have. However, TiAl alloys are generally brittle compared to other steel materials and titanium alloys, and therefore, there is a lack of toughness in parts that constantly hit (hit) the cam, such as the tip of the shaft of an engine valve for an automobile. It is a problem. Also, it is not easy to manufacture the alloy itself. For example, Ti
As a method for producing an Al alloy, a melting casting method is considered. In this case, Ti and Al have high reactivity and require a very special melting method of melting under high vacuum using a water-cooled copper crucible. In addition, it is necessary to maintain the vacuum for a long time to remove the adsorbed gas such as hydrogen and oxygen contained in the raw material, but actually the gas once adsorbed is not volatilized and removed only by the vacuum treatment, but rather is removed. Due to the long-time vacuum treatment, Al, which is one of the alloy components, is volatilized, causing a problem that the target component ratio changes. In addition, when the TiAl alloy is cast after being melted, defects such as generation of a large number of pores are involved, and time-consuming HIP processing is required to remove such defects. There was a disadvantage that the cost was high because the manufacturing equipment was special.

[0003] For this reason, a method utilizing a combustion synthesis method has been proposed as a method for producing a TiAl intermetallic compound. This utilizes the reaction heat of the elements constituting the Ti-Al intermetallic compound, and has the advantage that the production energy can be reduced with a relatively simple apparatus. There was a drawback that a porous body was formed due to great disaster, and a material having high strength could not be obtained. As described above, there is a problem that it is not easy to produce a TiAl alloy (intermetallic compound) having high purity, no component segregation, and a dense structure by any of the conventional melting method and combustion synthesis method. .

In such circumstances, a pulse current pressure sintering method has been proposed. It has been found that, compared with the conventional melting method or combustion synthesis method, a material excellent in reducing segregation of components of the material, densifying the structure and achieving high purity is obtained. However, although greatly reduced compared to the prior art, there is still a part where the crystal grains are coarsened in a part of the material.For example, in the case of an engine valve, for example, the shaft is connected under the head of the engine valve. In such a long material, pores tend to be generated in the middle of the material, and the problem of obtaining a uniform and dense structure throughout has not been sufficiently solved.

Further, since the length of the shaft portion of the engine valve is large with respect to the cross-sectional area, it is necessary to gradually add the sintering powder into the mold while dividing the powder into several parts. I tried to make a gap in the middle of the compact,
The density fluctuated or was unusable at all.
For this reason, a method has been adopted in which a long mold is used, and powder for sintering is put at once and pressed. However, in this case, there is a disadvantage that the sintering stroke must be lengthened only for mere compaction, and in the subsequent sintering, the heating current is wastefully consumed, and further, removal of the sintered product after sintering There was a problem that it was serious.

Further, as a major problem in the case of manufacturing a product of a TiAl alloy (intermetallic compound) by a pulse current pressing method, there is a bite between a sintered product and a molding die. In the case of the pulse current pressurization method, there is an advantage that sintering can be performed in a short time because an electric current is directly applied to a forming die or a punch, but heat resistance and high-temperature strength are required. Limited. However, graphite has a problem that it reacts with titanium, iron, chromium, and the like at high temperatures, and is severely consumed by mold parts and materials, which is a remarkable limitation in manufacturing efficiently and at low cost.

Therefore, in order to prevent such a reaction, a device such as inserting a graphite sheet different from the molding die or applying a powder of boron nitride (BN) as a release (release) material has been devised. It has been done. However, these also react with Ti and Al at a high sintering temperature, so that the sintering surface becomes rough and the product accuracy decreases, and the sintered body bites into the graphite mold. 2-3
The mold is often broken once, usually once, which is a serious problem in practical use.

Even when the above graphite sheet is used, it reacts with the sintered body, and when boron nitride (BN) is used,
It decomposes at high temperatures, producing hard titanium nitride and titanium boride. For this reason, after sintering at a set temperature of 1100 ° C, which is the maximum temperature at which the reaction with Ti and Al does not occur, take out once, heat-treat it in another furnace at 1300 ° C, and obtain a necessary structure. Has been taken. However, such a process is complicated and there is a problem that it is difficult to control the temperature and adjust the material.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a TiAl alloy, particularly a sintered body having an umbrella portion and a shaft portion, such as an engine valve, and a TiAl alloy sintered by a pulse current pressurization. When manufacturing the consolidated turbine blade, shaft, rocker arm, etc., it is intended to suppress the coarsening of the crystal grains of the sintered body, suppress the generation of vacancies, and obtain a dense structure throughout. For example, by using a TiAl alloy for the umbrella portion that receives high-temperature heat and using a titanium-based alloy having high toughness at the tip of the shaft portion, the characteristics of the entire joined body can be improved, and more appropriate separation can be achieved. The use of a mold agent prevents pressure between the sintered product and the graphite mold for molding, enabling the molding mold to be used repeatedly, reducing costs and producing high quality TiAl alloys by pressure sintering. Body manufacturing method and strength and durability Excellent engine valve,
It is an object to obtain a joined body such as a turbine blade and a rocker arm.

[0010]

Means for Solving the Problems Based on the above findings,
The present invention provides 1) Ti _1-x Al _x (0.39 ≦ x ≦ 0.
59, x: atomic fraction), a mixed powder or alloy powder or a sintering powder containing these as a main component, and a Ti-based alloy (including pure Ti; the same applies hereinafter) powder or Ti-based alloy other than the above. When joining the ingot and sintering at the same time,
Punch or die, and the upper and lower punches of the green compact
Alternatively, the upper surface of the die and the lower surface of
Process for producing a TiAl-Ti based alloy sintered joined body, which comprises sintering, 2) TiAl powder is above 1, characterized in that a mechanical alloying powder) according TiAl-
3) 850-100
The method for producing a TiAl-Ti-based alloy sintered joined body according to the above 1) or 2), wherein the sintered body is subjected to pressure sintering at 0 ° C. 4) Ti _1-x Al _x (0.39 ≦ x ≦ 0.59,
x: atomic fraction), a mixed powder or an alloy powder or a sintering powder containing these as a main component, and a Ti-based alloy (including pure Ti; the same applies hereinafter) powder or a Ti-based alloy ingot other than the above. After joining with the body at the same time as sintering,
A method for producing a TiAl-Ti alloy sintered joined body, comprising extruding a TiAl alloy portion at 300 ° C;
5) The TiAl- according to the above 4), wherein superplastic extrusion is performed at a strain rate of 1 × 10 ⁻² to 1 × 10 ^−5.
Method for manufacturing Ti-based alloy sintered joined body, 6) From upper punch or die with upper electrode, upper graphite mold or die having molding space, graphite die for lower sintering or lower punch or die with lower electrode The upper graphite mold or die is filled with a mixed powder or alloy powder of Ti and Al or a sintering powder containing these as a main component, and is continuously connected to the sintering powder by using a Ti-based alloy. Filling or arranging a powder or a Ti-based alloy ingot and sintering the powder under current and pressure simultaneously with joining the TiAl alloy sintered body and the Ti-based alloy , the upper punch or the lower surface of the die and the powder compact Top of body
The upper surface of the lower punch or die and the lower surface of the compact are electrically connected.
Manufacturing method of TiAl-Ti based alloy sintered joint characterized by being insulated and sintered , 7) upper punch or die having upper electrode, upper graphite mold or die having molding space, lower sintering Using a molding apparatus consisting of a lower punch or a die having a lower graphite electrode or a lower electrode, filling the upper graphite die or die with a mixed powder of Ti and Al or an alloy powder or a sintering powder containing these as a main component. And a Ti-based alloy powder or a Ti-based alloy ingot is filled or arranged continuously with the sintering powder, and the powder is subjected to current pressure sintering and, at the same time, the TiAl alloy sintered body and the Ti-based alloy are joined. After doing
A method for producing a TiAl-Ti-based alloy sintered joined body characterized by extruding a TiAl alloy portion at 1000 to 1300 ° C. 8) A graphite mold for lower sintering after joining TiAl and a Ti-based alloy. 8. The TiAl-Ti-based alloy sintered joined body according to claim 7, wherein the lower punch or the die provided with the lower electrode is replaced with an extrusion die, or the extrusion die is added and extruded. Manufacturing method, 9)
Lower surface of upper punch or die and upper and / or lower surface of compact
The upper surface of the punch or die and the lower surface of the compact are electrically disconnected.
4), 5), 7) above, characterized in that they are edged and sintered.
Or 8) a method for producing a TiAl-Ti-based alloy sintered joined body according to any one of the above items.

[0011]

Next, the present invention will be described with reference to the drawings. FIG. 1 is an explanatory sectional view showing an example of a sintering and joining apparatus used in the present invention. As shown in FIG. 1, the present apparatus includes an upper punch 1, an upper graphite mold 2 having a molding space, and a lower graphite mold 3. If necessary, a lower punch can be arranged. FIG. 1 shows an example of manufacturing an engine valve, and a graphite type or the like has an engine valve-shaped space. Note that this example is merely a preferable example, and the present invention is not limited to this example. For example, a turbine blade (blade), a rocker arm, which requires high-temperature corrosion resistance and high-temperature specific strength, And composite pipes. The upper graphite mold 2 also serves as a die in an extrusion process described later. Upper and lower graphite molds 2, 3
Not only that, the upper punch 1 and the lower punch can also be made of graphite in order to maintain heat resistance. Electric energy is supplied from an upper or lower electrode (not shown), and the sintering powder is heated and sintered through the graphite mold.

First, a Ti-based alloy powder or T
The i-base alloy ingot 4 is filled or arranged. This “Ti-based alloy ingot” is described in comparison with the Ti-based alloy powder, and has a necessary strength as a shaft of an engine valve by processing such as melting, casting, and rolling heat treatment of the Ti-based alloy. As described above. That is, the shaft for the engine valve or the like may be a sintered Ti-based alloy sintered body obtained by sintering simultaneously with the sintering of the TiAl alloy, or may be a Ti-based alloy ingot as described above. . Typical Ti-based alloys include α-type alloys such as Ti-5Al-2.5Sn, α + β-type alloys such as Ti-6Al-4V, and β-type alloys such as Ti-10V-2Fe-3Al. However, these can be selected and used according to the purpose. In particular, a titanium-based alloy having high strength and toughness is used for a shaft for an engine valve or the like. FIG. 1 shows such a Ti-based alloy ingot 4.

Next, a mixed powder of Ti and Al, an alloy powder, or a sintering powder 5 containing these as a main component is filled in the upper graphite mold 2. As described above, Ti and Al are main components, but Cr, Mo, W, Nb, and M are used as secondary components of the sintering powder for the purpose of improving mechanical properties and corrosion resistance.
n, V, Ni, Co, Cu, Zr, Hf, Sn, Zn,
One or more of B and TiB ₂ can be added in a range not exceeding 10 wt%. In order to further improve oxidation resistance, Si, P, SiC, TiC,
One or more of ZrC, VC, WC, MoC,
It can be added in a range not exceeding 20 wt%. As a material of the sintering powder 5, a mechanical alloying powder is preferable. As a raw material for sintering, a mixed powder or alloy powder of Ti and Al or a sintered powder containing these as a main component can be used, and mechanical alloying (MA) powder is particularly preferable. TiAl mechanical alloying (M
A) The powder is, for example, 3.5 ma of hydrogen subjected to hydrogen absorption treatment.
sponge titanium and aluminum powder containing ss% or more,
It can be obtained by ball milling the particles or pieces in an argon atmosphere or vacuum. The sponge titanium that has been subjected to the hydrogen absorption treatment is easily embrittled, and is finely pulverized to easily achieve alloying with aluminum. Further, during sintering, dehydrogenation is performed at a temperature of about 500 ° C., and since the atmosphere during sintering is kept reducible, oxidation is suppressed, and the quality of the sintered body is further improved.

The ratio of Ti to Al is Ti _1-x Al
_x (0.39 ≦ x ≦ 0.59, x: atomic fraction). Other than this ratio, places exposed to high-temperature exhaust gas,
For example, when used for an umbrella portion of an engine valve or the like, heat resistance is not sufficient. In addition to Ti and Al, in order to further improve mechanical properties and corrosion resistance as a secondary component, C
r, Mo, W, Nb, Mn, V, Ni, Co, Cu, Z
One or more of r, Hf, Sn, Zn, B, and TiB ₂ can be added in a range not exceeding 10 wt%. In order to further improve oxidation resistance, S
i, P, SiC, TiC, ZrC, VC, WC, MoC
Or two or more of them can be added in a range not exceeding 20 wt%. And these additional components do not prevent the combined use. A release agent 6 of alumina or boron nitride (BN) is applied as a reaction inhibitor to a contact portion between graphite such as an upper and lower punch or a die and a green compact or a sintered body. It is not preferable that the release agent 6 generates cracks after drying or peels off easily. After applying and drying the release agent 6, it is necessary to have a sufficient peeling (adhesion) strength so as not to peel off in a step of filling the sintered powder with the sintered powder and using this as a compact.

The use of a reaction inhibitor such as alumina or boron nitride (BN) as the release agent 6 is extremely effective in preventing the bite between the sintered product and the graphite mold for molding. The release agent 6 also functions as an electric insulator during sintering. In particular, by using such a release agent 6, the release agent does not react with the graphite mold until it is in a molten state at a high temperature of about 1460 ° C., and the sintered body can be easily formed from the graphite mold after sintering. Can be separated. The use of alumina or boron nitride (BN) as the release agent 6 can be used not only for the production of sintered compacts using a graphite mold for molding such as hot pressing, but also for a graphite mold for current pressure sintering. it can. Thereby, the use frequency of the graphite mold for molding is increased, which greatly contributes to cost reduction. In addition, BN (boron nitride) lubricant plays an important role for extrusion described later. BN (boron nitride) lubricant is applied to the surface of the graphite mold (die) 2 and used.

Next, after the above sintering powder is compacted and pressed into the lower graphite mold 2, pulse current pressure sintering is performed in the state shown in the figure. The atmosphere during sintering is vacuum (for example, a degree of vacuum of 10 ^−3).
Pa), and sintering is carried out at 850 to 1000 ° C. under a pressure of 10 to 100 K / min, preferably 10 to 40 K / min, and a pressure of 45 to 70 MPa. The heating temperature is 1000 ° C. or less at which no crystal grains grow. It is particularly necessary for the TiAl alloy sintered body to have fine crystal grains in the superplastic extrusion processing in the next step. Electric energy supplied from the upper electrode or the lower electrode via the upper and lower punches is not directly supplied to the sintering powder 5 but is supplied to the lower graphite mold 2 once because the alumina coating 6 which is an electric insulator is present. Then, the graphite mold 2 is sintered through heating. As a result, a rapid synthesis reaction of a mixed powder or an alloy powder of Ti and Al or a sintered powder containing these as a main component can be suppressed, for example, the crystal grains of an umbrella portion and a shaft portion of an engine valve become coarse, and There is an effect that a dense structure can be obtained over the whole without generating voids on the way.
Further, the present invention has an excellent effect of preventing the reaction between TiAl and the graphite mold.

It is more important that the Ti-based alloy ingot 4 and the TiAl sintered body are tightly connected to each other at the current pressure sintering stage. A flat test piece was prepared so that the joint was at the center after extrusion, which was described later, and a bending test was performed. The fracture occurred not in the joint but in the base material of the TiAl sintered body, and the joint had sufficient strength. Was. The bending strength of the joint was 850 MPa, which was almost the same as that of the base material of the TiAl sintered body. The above Ti-based alloy ingot 4
Alternatively, the same result was obtained when the Ti-based alloy powder was sintered simultaneously with the sintering of the TiAl alloy. Also in this case, the part in contact with the graphite mold is made of alumina or boron nitride (BN).
A release agent 6 is applied.

Next, after sintering the TiAl alloy by electric current pressure sintering and simultaneously joining the TiAl alloy sintered body and the Ti-based alloy, the TiAl alloy part is BN (boron nitride) at 1000-1300 ° C. Extrude through a lubricated die. It is preferable to perform superplastic extrusion at a strain rate of 1 × 10 ⁻² to 1 × 10 ⁻⁵ . As described above, Ti
Since the Al alloy sintered body has a fine crystal grain structure, extrusion processing is easy. At the time of this extrusion, as shown in FIG. 2, a graphite die for lower sintering or a lower punch or die having a lower electrode is replaced with an extrusion die 7 or the extrusion die is extended and extruded. . For example, 7mmφ
8mmφ instead of graphite mold 3 for lower sintering with hollow part
The extrusion is performed by replacing the extrusion die 7 having the hollow portion of the above.

As a result, in the example of the engine valve, the head portion which is most affected by the high temperature exhaust gas and the shaft portion adjacent to the head portion are made of a TiAl alloy sintered body, and are integrally formed with the head portion by extrusion. Accordingly, a composite material having high toughness can be obtained by maintaining the high-temperature strength between the head portion and the shaft, and using a Ti-based alloy at the tip of the shaft portion in contact with the cam.
FIG. 3 shows a schematic explanatory view of an example of the engine valve thus obtained. Reference numeral 9 denotes an umbrella portion of an engine valve, a shaft 8 serving as an extruded portion connected to the umbrella portion is a TiAl alloy sintered body of the same material as the umbrella portion, and a lower shaft 10 is a Ti-based alloy.
As described above, the shaft joint between the TiAl alloy sintered body and the Ti-based alloy has a strength of 800 MPa. As described above, by mainly using Ti and Al as main components, it is possible to reduce the weight, and for example, it is important that greatly affects the weight reduction of the engine. Originally, a titanium-aluminum alloy (intermetallic compound) is excellent in high-temperature corrosion resistance and high-temperature specific strength. Therefore, the method of the present invention, which can reduce the weight of an engine valve or the like at low cost, has an excellent effect. As described above, mainly the engine valve has been mainly described, but the present invention is not limited to this application, and the TiA according to the present invention is not limited to this application.
The joined body of the l-alloy sintered body and the Ti-based alloy is a composite pipe, turbine blade,
It can also be used for rocker arms. And this specific example is only an example, and is not limited to this example. That is, the present invention includes other aspects or modifications included in the technical concept of the present invention.

[0020]

As an alternative to the conventional heat-resistant steel, the engine valve, turbine, composite pipe, rocker arm, etc. can be further reduced in weight. For example, in the case of the engine valve, the head and shaft are made of TiAl alloy. As a sintered body, heat resistance to high-temperature exhaust gas is improved, and the tip of the shaft is T
By using an i-base alloy and a material that can withstand contact with the cam, the durability of the engine valve can be improved. Further, as described above, the sintering of the TiAl alloy and the tip of the shaft of the Ti-based alloy can be performed at the same time, thereby reducing the energy cost and simplifying the process.
It has an excellent feature that the bonding strength between the Al alloy shaft and the tip of the Ti-based alloy shaft can be maintained. In addition, the use of alumina or BN (boron nitride) as a release agent prevents bite between the sintered product and the graphite mold for molding, does not react with the graphite mold, and the sintering from the graphite mold after sintering. Could be easily separated. As a result, a sintered body having extremely high dimensional accuracy can be obtained, and the use frequency of the graphite mold for molding is increased, which greatly contributes to cost reduction. In addition, this release agent functions as an electrical insulator during sintering and suppresses the rapid synthesis reaction of the sintered powder. This has an excellent feature that a dense structure can be obtained over the whole without generating voids in the middle.

[Brief description of the drawings]

FIG. 1 is an explanatory cross-sectional view showing an example of the present apparatus provided with an upper punch, an upper graphite mold having a molding space, a lower graphite mold, and the like.

FIG. 2 is an explanatory cross-sectional view showing an example of an apparatus in which a lower graphite mold has been removed and replaced with an extrusion mold.

FIG. 3 is a schematic explanatory view of an engine valve manufactured by applying the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 upper punch 2 upper graphite mold 3 lower graphite mold 4 tip end of Ti-based alloy shaft 5 TiAl alloy sintered powder or sintered body 6 release agent 7 extrusion die 8 extruded portion TiAl alloy shaft 9 TiAl alloy head 10 Ti Base alloy shaft tip

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI F01L 3/02 F01L 3/02 G 3/24 3/24 D (72) Inventor Yoshinobu Saito Murata-cho, Shibata-gun, Miyagi Prefecture Nishigaoka 23 Tohoku Special Steel Co., Ltd. (72) Inventor Yoshitaka Nishizawa, Murata-cho, Shibata-gun, Miyagi Prefecture Nishigaoka 23 Tohoku Special Steel Co., Ltd.Examiner, Kazuma Yamamoto (56) References JP 4-118182 (JP, A) JP-A-7-3306 (JP, A) JP-A-9-300024 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B22F 7/04 B22F 3/14 101

Claims (9)

(57) [Claims] 1. The method according to claim 1, wherein Ti _1-x Al _x (0.39 ≦ x ≦ 0.
59, x: atomic fraction), a mixed powder or alloy powder or a sintering powder containing these as a main component, and a Ti-based alloy (including pure Ti; the same applies hereinafter) powder or Ti-based alloy other than the above. When joining the ingot and sintering at the same time,
Punch or die, and the upper and lower punches of the green compact
Alternatively, the upper surface of the die and the lower surface of
A method for producing a TiAl-Ti-based alloy sintered joint, comprising: 2. The TiAl—Ti according to claim 1, wherein the TiAl powder is a mechanical alloying powder.
A method for producing a base alloy sintered joint. 3. The method for producing a TiAl—Ti-based alloy sintered joined body according to claim 1, wherein the sintered body is pressure-sintered at 850 to 1000 ° C. 4. The method according to claim 1, wherein Ti _1-x Al _x (0.39 ≦ x ≦ 0.
59, x: atomic fraction), a mixed powder or alloy powder or a sintering powder containing these as a main component, and a Ti-based alloy (including pure Ti; the same applies hereinafter) powder or Ti-based alloy other than the above. After joining the ingot and sintering simultaneously, 100
A method for producing a TiAl-Ti alloy sintered joint, comprising extruding a TiAl alloy portion at 0 to 1300 ° C. 5. The method according to claim 4, wherein the superplastic extrusion is performed at a strain rate of 1 × 10 ⁻² to 1 × 10 ⁻⁵ . 6. A molding apparatus comprising an upper punch or a die having an upper electrode, an upper graphite mold or a die having a molding space, a lower sintering graphite mold or a lower punch or a die having a lower electrode. Ti and A for graphite mold or die
l mixed powder or alloy powder or a sintering powder containing these as a main component and filled or arranged with a Ti-based alloy powder or a Ti-based alloy ingot continuously with the sintering powder. When the TiAl sintered body and the Ti-based alloy are joined at the same time when the
The lower surface of a and the upper surface of the green compact and the lower punch or die
A method for producing a TiAl-Ti-based alloy sintered joined body, characterized in that a surface and a lower surface of a green compact are electrically insulated and sintered . 7. A molding apparatus comprising an upper punch or a die having an upper electrode, an upper graphite mold or a die having a molding space, a lower sintering graphite mold or a lower punch or a die having a lower electrode. Ti and A for graphite mold or die
l mixed powder or alloy powder or a sintering powder containing these as a main component, and filled or arranged with a Ti-based alloy powder or a Ti-based alloy ingot continuously with the sintering powder; After sintering the powder under current pressure and simultaneously joining the TiAl sintered body and the Ti-based alloy, 1000-1300 ° C
Extruding the TiAl alloy part with T
A method for producing an iAl-Ti-based alloy sintered joint. 8. After joining TiAl and a Ti-based alloy,
8. The TiAl-Ti base according to claim 7, wherein a graphite die for lower sintering or a lower punch or a die provided with a lower electrode is replaced with an extrusion die, or the extrusion die is extended and extruded. A method for producing an alloy sintered joint. 9. The method of manufacturing a green compact, comprising:
The upper surface and the upper surface of the lower punch or die and the lower surface of the green compact
5. The method according to claim 4, wherein the sintering is performed while being electrically insulated.
The method for producing a TiAl-Ti-based alloy sintered joint according to any one of 5, 7, and 8 .