JPH1121645A - Ni-base superalloy having heat resistance, production of ni-base superalloy having heat resistance, and ni-base superalloy parts having heat resistance - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a directionally solidified Ni-base superalloy having high temp. strength comparable with that of the conventional first-generation Ni-base single crystal alloy and also having excellent corrosion resistance and oxidation resistance in high temp. combustion gas, production of the Ni-base superalloy, and parts made of the Ni-base superalloy. SOLUTION: This Ni-base superalloy having heat resistance can be produced by applying unidirectional solidification process to an Ni-base superalloy material which has a composition consisting of, by weight, 8-14% Cr, 7-12% Co, 5-8% Al, 1-4% Ti, 3-8% W, 3-8% Ta, 0.5-2% Mo, 0.5-2.5% Nb, 1.5-3% Ir, 0.05-0.2% C, 0.01-0.03% B, 0.02-0.05% Zr, and the balance Ni with inevitable impurities and satisfying 6%<=Al+Ti, 2<=Al/Ti, and W+Ta+Mo<=14%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a directionally solidified N which has excellent high-temperature corrosion resistance and high-temperature strength in components used for a long time at high temperatures, especially in industrial gas turbines.
The present invention relates to an i-base heat-resistant superalloy, a method for producing the Ni-base heat-resistant superalloy, and a Ni-base heat-resistant superalloy part.

[0002]

2. Description of the Related Art Turbine blades, which are exposed to the most severe operating environment in response to an increase in combustion temperature accompanying a high output and high efficiency of a gas turbine engine, are made of a polycrystalline ordinary cast alloy by using crystal grains in a stress loading direction. A transition has been made to unidirectionally solidified alloys without boundaries and single crystal alloys without any grain boundaries.

[0003] In fact, a Ni-based directionally solidified alloy is applied as a turbine blade of an aircraft engine.
ene80H, PWA1422, CM247LC and the like are used.

[0004] Turbine blades for aircraft, such as jet engines, rotate at high speed and are susceptible to centrifugal force, and cracks are likely to occur at crystal grain boundaries that cross the longitudinal direction of the turbine blades. That is, when the rod-shaped object is pulled, cracks are easily generated from the surface layer portion of the crystal grain boundary which is perpendicular to the direction in which the rod is pulled.
Therefore, in order to cope with such cracks, a method has been developed in which a crystal grain boundary itself perpendicular to the longitudinal direction of the turbine blade is eliminated. This method is unidirectional solidification. Unidirectional solidification is a method in which when an alloy such as a Ni-base heat-resistant alloy is solidified from a molten state, cooling is performed from a lower end of the alloy material and a crystal is grown unidirectionally from the cooled end. It is. By applying the above method to a machine component having a complicated curved surface such as a turbine blade and growing crystals in the longitudinal direction of the turbine blade, it is possible to obtain a turbine blade having excellent creep rupture strength and the like.

However, the turbine blade obtained by unidirectional solidification has a structure in which several crystals are elongated vertically, and the boundaries between the crystals are not completely straight but slightly zigzag or oblique. It has become. Therefore, the turbine blade cannot obtain strength particularly at a high temperature.

Considering only the high-temperature strength, the Ni-based unidirectional solidified alloy is superior to the Ni-based ordinary cast alloy according to the conventional manufacturing method, but is more effective than the Ni-based unidirectionally solidified alloy. Is known to be better. However, the yield of the Ni-based single crystal alloy is poor, and at present, the cost is about three times that of the Ni-based unidirectionally solidified alloy.

[0007] In recent years, with the increase in efficiency and temperature of industrial gas turbines, conventional gas cast alloys have also been replaced with unidirectional solidified alloys in industrial gas turbines. However, it is becoming difficult to obtain high-temperature strength that satisfies the demands for high temperature, high efficiency, and high output of a rapidly developing gas turbine. In order to solve this problem, a Ni-based directionally solidified alloy called second generation (for example, Rene 142, PWA 1426, CM 186L) to which about 3% of Re, which is a rare earth element, is added.
C) has been developed. The second-generation Ni-based directionally solidified alloy is a first-generation Ni-based single crystal alloy (for example, Rene).
It has a high temperature strength comparable to N4, PWA1480, CMSX-2). However, there are major drawbacks, such as an increase in material cost due to the addition of expensive Re and an increase in manufacturing cost due to a decrease in castability.

Furthermore, industrial gas turbines use fuels containing heavy oil-based impurities more than aircraft gas turbines, so that the corrosive environment is severer. In addition, the continuous operation period is extremely long, and the interval between inspections is very long. Therefore, the rate of progress of corrosion when the coating is peeled is particularly important. Therefore,
In an industrial gas turbine, high-temperature corrosion resistance and oxidation resistance in a high-temperature combustion gas must be higher than that of a conventional Ni-based directionally solidified alloy.

[0009]

However, although the above-mentioned Ni-based directionally solidified alloy has excellent high-temperature strength, it has been required to increase the temperature, efficiency and output of a gas turbine which has been rapidly developing in recent years. In response to the demands, it has been difficult to obtain a Ni-based directionally solidified alloy having a sufficiently satisfactory high-temperature strength with conventional ones. In addition, in high-temperature combustion gas, Ni that satisfies high corrosion resistance and oxidation resistance
A base directionally solidified alloy has not yet been obtained.

The present invention has been made to address such a problem, and appropriately adjusts the chemical composition of a conventional Ni-based directionally solidified alloy and adds an existing alloy by adding a new alloy element. It is an object of the present invention to provide a unidirectionally solidified Ni-based heat-resistant superalloy having high-temperature strength comparable to that of the first-generation Ni-based single crystal alloy, and excellent corrosion resistance and oxidation resistance as compared with conventional ones.

In the production of the Ni-base heat-resistant superalloy, by setting various conditions such as heat treatment conditions and cooling rates, it is possible to obtain excellent high-temperature characteristics.
An object of the present invention is to provide a method for producing an i-base heat-resistant superalloy.

Further, by applying the Ni-base heat-resistant superalloy obtained as described above to an industrial gas turbine or the like, a Ni-base heat-resistant superalloy having excellent corrosion resistance and oxidation resistance even in a high-temperature combustion gas. The purpose is to provide alloy parts.

[0013]

Means for Solving the Problems The present inventors have developed a unidirectionally solidified Ni-based heat-resistant superalloy having excellent high-temperature strength, high-temperature corrosion resistance and high-temperature oxidation resistance, a method for producing the same, and parts thereof. As a result of conducting research for the purpose, the present invention has been achieved.

The Ni-base heat-resistant superalloy according to claim 1 is, by weight%, 8 to 14% of Cr, 7 to 12% of Co, and 5 of Al.
-8%, Ti: 1-4%, W: 3-8%, Ta: 3-8
%, Mo: 0.5 to 2%, Nb: 0.5 to 2.5%, I
r: 1.5-3%, C: 0.05-0.2%, B: 0.
0.01 to 0.03%, Zr: 0.02 to 0.05%, the balance consisting of Ni and unavoidable impurities, and 6%
% ≦ Al + Ti, 2 ≦ Al / Ti, W + Ta + Mo ≦ 1
4%.

In the present invention, the reasons for limiting the components as described above will be described.

Cr (chromium) has an effect of improving high-temperature corrosion resistance and also contributes to oxidation resistance. The reason for defining the Cr content to be 8 to 14% is that if the content is less than 8%, the desired high-temperature corrosion resistance cannot be secured, and if the content exceeds 14%, the γ 'phase (Ni (nickel )
Not only the precipitation of the intermetallic compound Ni ₃ Al) and Al (aluminum), but also an undesirable embrittlement phase called a TCP phase (σ phase) is generated, and the high-temperature strength is reduced. That's why.

Co (cobalt) has a γ 'phase (Ni and Al
Is an element that has the effect of lowering the solid solution temperature of the intermetallic compound Ni ₃ Al) to facilitate the solution treatment, and also has the effect of improving the high-temperature corrosion resistance due to the action of solid solution strengthening of the γ phase. . The reason for defining the Co content to be 7 to 12% is that if the content is less than 7%, the desired effect cannot be obtained, and if the content exceeds 12%, the precipitation of the γ 'phase as a precipitation strengthening phase is suppressed. This is because not only does this result, but also the high-temperature strength decreases.

Al (aluminum) is a main alloying element for generating a γ 'phase, and also contributes to oxidation resistance by forming an Al oxide on the surface. The reason that the content of Al is specified as 5 to 8% is that if the content is less than 5%, a γ 'phase with a sufficient volume fraction to obtain good creep rupture strength cannot be generated, and If the content exceeds 8%, the solution treatment becomes difficult, the amount of undissolved γ 'increases, and the creep rupture strength decreases.

Ti (titanium) can substitute for Al in the γ 'phase, and the resulting phase is Ni ₃ (Al, Ti), which helps solid solution strengthening of the γ' phase. Further, as described later, an intermetallic compound is formed with Ir to contribute to high-temperature strength,
It is an element that promotes the generation of Cr oxide having excellent high-temperature corrosion resistance. The reason that the content of Ti is defined as 1 to 4% is that if the content is less than 1%, a γ 'phase having a sufficient volume fraction to obtain good creep rupture strength cannot be formed. If the content exceeds 4%, Ti tends to form a eutectic γ 'phase, and the solution treatment temperature cannot be sufficiently increased to lower the melting point of the superalloy. Therefore, it is difficult to completely dissolve the eutectic γ 'phase in a solid solution, and the creep rupture strength is reduced. Furthermore, it is harmful to oxidation resistance.

As is clear from the above, a γ 'phase is formed,
For strengthening, it is important to add two alloy elements, Al and Ti, together.

In the present invention, the total amount of addition of the two alloy elements, Al and Ti, is set to 6% ≦ Al + Ti. The reason for this definition is that when the total amount of addition is less than 6%, a sufficient volume ratio of γ The reason is that the creep rupture strength is lowered without forming the 'phase. However, Al and T
Even if the total amount of i added is in the range of 6% ≦ Al + Ti, T
When the i content is excessive, there is a problem that high-temperature strength and oxidation resistance are reduced. Therefore, the Al / Ti ratio is set to 2 ≦ Al so that Al is the main alloying element for generating the γ ′ phase.
By defining / Ti, it is possible to maximize the generation amount of the γ 'phase and the solid solution strengthening within a range that does not cause a decrease in high-temperature strength or oxidation resistance.

Nb (niobium) is γ 'like Al and Ti.
It is an element that forms a phase, and is an element that solid-solution strengthens the γ 'phase. Further, Nb forms an intermetallic compound Nb ₃ Al with Al. Nb ₃ Al has a melting point of 2,000 ° C. or higher, so that it is possible to obtain superior high-temperature strength due to precipitation of the Nb ₃ Al phase. The reason that the content of Nb is defined as 0.5 to 2% is that if the content is less than 0.5%, a sufficient amount of γ ′ phase and Nb ₃ Al cannot be generated, Exceeds 2.5%, the oxidation resistance is significantly reduced.

Ir (iridium) has a very high melting point of 2440 ° C., has an fcc structure, and has the same LI as Ti and γ ′ phase.
An Ir ₃ Ti phase having _two structures is formed. Ir ₃ Ti phase is γ '
Since the phase is superior in stability at a higher temperature than the phase, it is possible to further improve the high-temperature strength by precipitating this phase. The reason that the content of Ir is defined as 1.5 to 3% is that if the content is less than 1.5%, a sufficient amount of Ir ₃ T
This is because an i-phase cannot be formed and excessive addition exceeding 3% lowers ductility.

W (tungsten) is an alloy element that forms a solid solution in the γ phase and the γ ′ phase to strengthen the solid solution of both phases. The reason that the content of W is specified to be 3 to 8% is that if the content is less than 3%, the strength of the γ 'phase is remarkably reduced, and if the content exceeds 8%, α-W and This is because a so-called TCP phase is precipitated and the creep rupture strength is lowered.

Mo (molybdenum) is γ ′ similarly to Ta.
An element that forms a solid solution with the phase to strengthen the γ 'phase. The reason why the content of Mo is defined as 0.5 to 2% is that a content of at least 0.5% is necessary, and if it exceeds 2%, the TCP phase (α-Mo) which is an embrittlement phase like W is used. Phase) and lowers the creep rupture strength.

Ta (tantalum) is an element capable of forming a solid solution mainly in the γ ′ phase to strengthen the γ ′ phase and improving the coating characteristics of the Al oxide. When the content of Ta is 3 to
The reason why the content is specified as 8% is that if the content is less than 3%, the strength of the alloy becomes low, and if it exceeds 8%, it becomes difficult to form a solid solution of the eutectic γ 'phase, and the creep rupture strength Is to be reduced.

Since the three alloying elements W, Ta, and Mo described above have different solid solution strengthening functions, it is important to add all three alloying elements. In the present invention,
The total added amount of these three alloying elements is expressed as W + Ta + Mo ≦ 14.
%. The reason why the total amount of W, Ta, and Mo is defined as described above is that if the total amount is small, the solid solution strengthening of the γ phase and the γ ′ phase cannot be sufficiently exhibited. This is because corrosion resistance and oxidation resistance are significantly reduced. Thus, by defining the individual amounts and the total amounts of W, Ta, and Mo, it is possible to maximize the solid solution strengthening of the γ phase and the γ ′ phase within a range that does not lower the high-temperature strength and environmental characteristics.

C (carbon), B (boron) and Zr (zirconium) are elements that strengthen the crystal grain boundaries. However, excessive addition of these alloying elements adversely affects the high-temperature strength, so that C is 0.05 to 0.2%, B is 0.01 to 0.03%, and Zr is 0.02 to 0.3%. It was specified as 05%. In particular, if the content of C exceeds 0.2%, excess C is separated, forming carbides that serve as starting points of fatigue cracks, and lowering fatigue strength. When B and Zr are contained, excessive addition of both lowers ductility and toughness. However, by adding an element in the above range, the grain boundary is strengthened without lowering the high-temperature strength. It is possible to

The Ni-base heat-resistant superalloy according to claim 2 is, by weight%, 8 to 14% of Cr, 7 to 12% of Co, and 5: Al.
-8%, Ti: 1-4%, W: 3-8%, Ta: 3-8
%, Mo: 0.5 to 2%, Nb: 0.5 to 2.5%, I
r: 1.5-3%, C: 0.05-0.2%, B: 0.
0.01 to 0.03%, Zr: 0.02 to 0.05%, the balance consisting of Ni and unavoidable impurities, and 6%
% ≦ Al + Ti, 2 ≦ Al / Ti, W + Ta + Mo ≦ 1
It is characterized in that a 4% Ni-base heat-resistant superalloy material is unidirectionally solidified.

The components of the Ni-base heat-resistant superalloy in the present invention are the same as the components described in the first aspect.

Among the above-mentioned components, C, B and Zr are elements that strengthen the crystal grain boundaries and are indispensable elements in the directionally solidified superalloy. However, excessive addition of the elements C, B and Zr adversely affects the high-temperature strength, so that C is 0.05-0.2% and B is 0.01-0.03%.
% And Zr are defined as 0.02 to 0.05%.

In the present invention, to unidirectionally solidify the Ni-base heat-resistant superalloy means to align the crystal orientation of the Ni-base heat-resistant superalloy in one direction. In order to align the crystal orientation in one direction, it is only necessary to control the heat in one direction when solidifying the Ni-base heat-resistant superalloy material. In this way, the Ni-base heat-resistant superalloy is solidified in one direction and high-temperature fracture occurs. It is possible to obtain a Ni-base heat-resistant superalloy that does not include a crystal grain boundary perpendicular to the stress axis direction, which is the starting point of the heat treatment. Further, by unidirectionally solidifying the Ni-base heat-resistant superalloy having the component composition of the present invention, it is possible to further improve properties such as high-temperature strength as compared with conventional ones.

The method for producing a Ni-base heat-resistant superalloy according to claim 3 is characterized in that Ni, Cr, Co, Al, Ti, W, Ta, M
After the molten material containing o, Nb, Ir, C, B, and Zr is unidirectionally solidified, the molten material is heated to 120
The solution was heated to 0 ° C to 1250 ° C, subjected to a solution treatment in the same temperature range for 2 hours or more, rapidly cooled, and then cooled to 1050 ° C to
It is characterized by aging at 4 ° C. for 4 hours or more.

In the present invention, 1200 ° C. to 1250
Although the solution treatment is performed at 2 ° C. for 2 hours or more, by performing the solution treatment at the above temperature, it becomes possible to effectively remove the σ phase remaining on the crystal grain boundaries, and to obtain excellent high-temperature characteristics. It is possible to get.

Further, the temperature as in the present invention, by defining the processing method such as time, a desired LI ₂ structure responsible for high temperature strength to the gamma phase precipitates gamma 'phase (Ni 3 _(Al,
Ti)) and, in addition, the precipitation of Ir ₃ Ti and Nb ₃ Al can be confirmed, and a Ni-base heat-resistant superalloy having high-temperature strength can be obtained by the precipitation.

According to a fourth aspect of the present invention, there is provided the method for producing a Ni-base heat-resistant superalloy according to the third aspect, wherein the solution treatment and the subsequent aging treatment are continuously performed at a high temperature. At the time of solution treatment 1200 ° C ~ 125
The cooling rate from the temperature range of 0 ° C. to the temperature range of the aging treatment of 1050 ° C. to 1150 ° C. is set to 300 ° C./hour or more. The aging treatment is carried out for 4 hours or more at 1 to 1150 ° C.

In the present invention, even if the processing is performed by a method different from the method described in the third aspect, the same as in the third aspect, γ
The precipitate γ 'phase (Ni ₃ (Al, Ti)), which is the desired LI ₂ structure bearing high temperature strength in the phase, plus Ir ₃
Precipitation of Ti and Nb ₃ Al can be confirmed, and a Ni-based heat-resistant superalloy having high-temperature strength can be obtained by the precipitation.

The Ni-base heat-resistant superalloy according to claim 5 is, by weight%, 8 to 14% of Cr, 7 to 12% of Co, and 5: Al.
-8%, Ti: 1-4%, W: 3-8%, Ta: 3-8
%, Mo: 0.5 to 2%, Nb: 0.5 to 2.5%, I
r: 1.5-3%, Hf: 0.5-2%, Y: 0.15
0.3%, C: 0.05-0.2%, B: 0.01-
0.03%, Zr: 0.02-0.05%, the balance being Ni and unavoidable impurities, and 6% ≦ Al
+ Ti, 2 ≦ Al / Ti, and W + Ta + Mo ≦ 14%.

Hf (hafnium) and Y in the present invention
The reason for including a component other than (yttrium) is based on the same reason as described in claim 1.

In the present invention, the reason for adding Hf and Y is to obtain the long-term structural stability, high-temperature corrosion resistance and oxidation resistance of the Ni-base heat-resistant alloy. Further, in order to improve corrosion resistance and oxidation resistance at high temperatures, it is necessary to improve the adhesion of a protective film (for example, Cr ₂ O ₃ , Al ₂ O ₃ ) formed on the alloy surface. Hf and Y described above can improve the adhesion of the protective film.

The reason why the addition amount of Hf is specified to be 0.5 to 2% is that the addition of 0.5% or more significantly improves the adhesion of the protective film, but if it exceeds 2%, the Ni-based heat-resistant superalloy is This is because the melting point decreases and it becomes difficult to form a solid solution of the γ 'phase.

The reason why the addition amount of Y is specified to be 0.15 to 0.3% is that if the addition amount exceeds 0.3%, the growth of the protective film is promoted and peeling is caused. This is because high-temperature corrosion resistance and oxidation resistance characteristics are deteriorated.

The Ni-base heat-resistant superalloy according to claim 6 is, by weight%, 8 to 14% of Cr, 7 to 12% of Co, and 5 of Al.
-8%, Ti: 1-4%, W: 3-8%, Ta: 3-8
%, Mo: 0.5 to 2%, Nb: 0.5 to 2.5%, I
r: 1.5-3%, Hf: 0.5-2%, Y: 0.15
0.3%, C: 0.05-0.2%, B: 0.01-
0.03%, Zr: 0.02-0.05%, the balance being Ni and unavoidable impurities, and 6% ≦ Al
+ Ti + 2 ≦ Al / Ti, W + Ta + Mo ≦ 14% Ni-based heat-resistant superalloy material is unidirectionally solidified.

The components in the present invention are described in claim 5.
Same as described components.

In the present invention, N having the aforementioned components
By unidirectionally solidifying the i-base heat-resistant superalloy material,
It is possible to improve the long-term structural stability, high-temperature corrosion resistance, and oxidation resistance of the Ni-base heat-resistant superalloy.

The method for producing a Ni-base heat-resistant superalloy according to claim 7 is characterized in that Ni, Cr, Co, Al, Ti, W, Ta, M
After the molten material containing o, Nb, Ir, Hf, Y, C, B, and Zr is unidirectionally solidified, the material is heated to 1200 ° C. to 1250 ° C. in a vacuum or an inert atmosphere.
After solution treatment for more than an hour, quenched, then 1050 ° C
The aging treatment is performed at 1150 ° C. for 4 hours or more.

The present invention is the same as the production method according to the third aspect. However, the production method of the present invention regulates the treatment method such as temperature and time so that the desired high-temperature strength in the γ phase can be obtained. The precipitate γ ′ phase having the LI ₂ structure (Ni ₃ (A
l, Ti)), and in addition, the precipitation of Ir ₃ Ti and Nb ₃ Al can be confirmed, and a Ni-based heat-resistant superalloy having high-temperature strength can be obtained by these precipitations.

The method for producing a Ni-base heat-resistant superalloy according to claim 8 is a method for producing a Ni-base heat-resistant superalloy according to claim 7, wherein the solution treatment and the subsequent aging treatment are continuously performed at a high temperature. At the time of solution treatment 1200 ° C ~ 125
The cooling rate from the temperature range of 0 ° C. to the temperature range of the aging treatment of 1050 ° C. to 1150 ° C. is set to 300 ° C./hour or more. The aging treatment is carried out for 4 hours or more at 1 to 1150 ° C.

Also in the present invention, it is possible to obtain a Ni-base heat-resistant superalloy having the same effect as the fourth aspect of the present invention.

The Ni-base heat-resistant superalloy component according to claim 9 is
A turbine blade and other gas turbine engine parts are made of any one of the Ni-base heat-resistant superalloys according to the first, second, fifth, and sixth aspects.

In the present invention, the Ni-base heat-resistant superalloy component can be sufficiently applied as an industrial gas turbine component requiring high-temperature corrosion resistance, which has been difficult to use conventionally. In this case, in addition to high temperature strength and oxidation resistance,
It is possible to maximize the advantages of high temperature corrosion resistance.

That is, high efficiency and long-term operation of the industrial gas turbine can be realized, and the operating efficiency of the gas turbine can be greatly improved.

[0053]

Embodiments of the present invention will be described below with reference to the following examples.

Example 1 (Tables 1 to 3: FIGS. 1 to 4) In this example, a Ni-base heat-resistant superalloy material having the component composition shown in Table 1 was used.

As shown in Table 1, the specific composition of the Ni-base heat-resistant superalloy material is as follows:
%, Al 5.6%, Ti 2%, W 7%, Ta 5%, Mo
0.8%, Nb1%, Ir1.5%, Hf0.5%, Y
0.15%, C0.05%, B0.02%, Zr0.0
3%, with the balance being Ni-based and unavoidable impurities.

[0056]

[Table 1]

As shown in Table 2, after melting the above-mentioned Ni-base heat-resistant superalloy material, it was cast into a directionally solidified columnar crystal by a high-speed solidification method, and heated at 1220 ° C. in an inert atmosphere. The solution treatment was performed for 3 hours. Then 1
Aging treatment was performed at 080 ° C. for 4 hours to prepare a test piece.

Table 2 shows the above manufacturing method.

[0059]

[Table 2]

With respect to the test piece obtained in this example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. In the creep rupture test, a test piece was tested in the atmosphere at a temperature of 950 ° C. and a stress of 24.5 kgf / mm ² , and the creep rupture characteristics of rupture life (h) and elongation (%) were measured. The hot corrosion resistance test was performed using Na ₂ SO ₄
900 having a composition of (75%) + NaCl (25%)
The weight loss after immersion in a molten salt heated to 0 ° C. for 20 hours was measured and defined as the corrosion weight loss (mg / cm ² ). The oxidation resistance test was repeated every 8 hours in the air from room temperature to a temperature of 950 ° C., and the increase in oxidized mass after 100 cycles was measured and defined as the oxidized increase (mg / cm ² ).

The test results are shown in Table 3 and FIGS.

[0062]

[Table 3]

As shown in Table 3, the life in creep rupture characteristics was 336 hours, the elongation was 22%, and the weight loss in corrosion was 0.1%.
68 mg / cm ^2, oxidized amount was 0.31 mg / cm ^2.

Example 2 (Tables 1 to 3: FIGS. 1 to 4) In this example, a Ni-base heat-resistant superalloy material having the component composition shown in Table 1 was used.

As shown in Table 1, the specific composition of the Ni-base heat-resistant superalloy material is as follows:
%, Al 5.2%, Ti 3%, W 5.6%, Ta 5%,
Mo 0.8%, Nb 1%, Ir 2.5%, Hf 1%, Y
0.2%, C 0.07%, B 0.015%, Zr0.0
2%, with the balance being Ni-based and unavoidable impurities.

Using the above-mentioned Ni-base heat-resistant superalloy material, a test piece subjected to the same treatment as in Example 1 was produced.

For the test piece obtained in this example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, the life in the creep rupture property was 338 hours, the elongation was 26%, and the corrosion weight loss was 0.81 mg.
/ Cm ² , and the weight gain of oxidation was 0.27 mg / cm ² .
The test conditions are the same as in Example 1.

Example 3 (Tables 1 to 3: FIGS. 1 to 4) In this example, a Ni-base heat-resistant superalloy material having the component composition shown in Table 1 was used.

As shown in Table 1, the specific composition of the Ni-base heat-resistant superalloy material is as follows:
0%, Al 5.2%, Ti 3%, W 7%, Ta 5%, M
o1%, Nb2%, Ir2.5%, Hf1.4%, Y
0.3%, C0.05%, B0.015%, Zr0.0
3%, with the balance being Ni-based and unavoidable impurities.

Using the above-mentioned Ni-base heat-resistant superalloy material, a test piece subjected to the same treatment as in Example 1 was produced.

For the test piece obtained in this example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, the life in creep rupture characteristics was 387 hours, the elongation was 21%, and the corrosion weight loss was 0.50 mg.
/ Cm ² , and the weight gain by oxidation was 0.33 mg / cm ² .
The test conditions are the same as in Example 1.

Example 4 (Tables 1 to 3: FIGS. 1 to 4) In this example, a Ni-base heat-resistant superalloy material having the component composition shown in Table 1 was used.

As shown in Table 1, the specific composition of the Ni-base heat-resistant superalloy material is as follows: Cr 14%, Co8
%, Al 5.6%, Ti 2%, W 7%, Ta 5%, Mo
1%, Nb 1%, Ir 1.5%, Hf 0.5%, Y0.
2%, C 0.07%, B 0.02%, and Zr 0.05%, with the balance being Ni-based and unavoidable impurities.

Using the above-mentioned Ni-base heat-resistant superalloy material, a test piece subjected to the same treatment as in Example 1 was produced.

With respect to the test piece obtained in this example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, in creep rupture characteristics, the life was 340 hours, the elongation was 26%, and the corrosion weight loss was 0.62 mg.
/ Cm ² and the oxidation weight gain was 0.54 mg / cm ² .
The test conditions are the same as in Example 1.

Comparative Example 1 In this comparative example, C-1 and C-2 were used as two kinds of samples having different component compositions shown in Table 1.

As shown in Table 1, the specific composition of Sample C-1 was 6.4% by weight of Cr and 4.8% of Co by weight percent.
%, Al 5.6%, Ti 2%, W 7%, Ta 5%, Mo
0.8%, Nb1%, Ir0%, Hf1%, Y0.2
%, 0.05% of C, 0.02% of B, and 0.02% of Zr, with the balance being Ni-based and unavoidable impurities.

As shown in Table 1, the specific composition of Sample C-2 was as follows: Cr 16%, Co 4.8%,
Al 5.6%, Ti 2%, W 7%, Ta 5%, MoO.
8%, Nb1%, Ir0%, Hf1%, Y0.2%, C
The composition contained 0.05%, 0.02% of B, and 0.02% of Zr, and the balance was Ni-based and unavoidable impurities.

Using the above-mentioned Ni-base heat-resistant superalloy material, a test piece subjected to the same treatment as in Example 1 was produced.

For the test piece obtained in this comparative example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, the sample C-1 had a life of 313 hours in creep rupture characteristics, an elongation of 22%, a weight loss of corrosion of 3.06 mg / cm ² , and a weight gain of oxidation of 0.42 mg / c.
It was m ^2. Sample C-2 had a creep rupture life of 212 hours, an elongation of 18%, a weight loss of corrosion of 0.53 mg / cm ² , and a weight gain of oxidation of 0.41 mg / cm ² .
It was ² . The test conditions are the same as in Example 1.

Comparative Example 2 In this comparative example, C-3 and C-4 were used as two kinds of samples having different component compositions shown in Table 1.

As shown in Table 1, the specific composition of Sample C-3 was, as weight percent, 14% Cr, 2.2% Co,
Al 5.6%, Ti 2%, W 7%, Ta 5%, MoO.
8%, Nb1%, Ir0%, Hf1%, Y0.2%, C
The composition contained 0.05%, 0.02% of B, and 0.02% of Zr, and the balance was Ni-based and unavoidable impurities.

As shown in Table 1, the specific composition of Sample C-4 was as follows: Cr 12%, Co 14%, A
l5.6%, Ti 2%, W 7%, Ta 5%, Mo 0.8
%, Nb1%, Ir0%, Hf1%, Y0.2%, C
The composition contained 0.05%, 0.02% of B, and 0.02% of Zr, and the balance was Ni-based and unavoidable impurities.

Using the above-mentioned Ni-base heat-resistant superalloy material, a test piece subjected to the same treatment as in Example 1 was produced.

For the test piece obtained in this comparative example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, in Sample C-3, the life in creep rupture characteristics was 271 hours, the elongation was 22%, the corrosion weight loss was 1.42 mg / cm ² , and the oxidation weight gain was 0.46 mg / c.
It was m ^2. Sample C-4 had a creep rupture life of 216 hours, an elongation of 21%, a weight loss of corrosion of 0.56 mg / cm ² , and a weight gain of oxidation of 0.31 mg / cm 2.
It was ² . The test conditions are the same as in Example 1.

Comparative Example 3 In this comparative example, C-5 and C-6 were used as two kinds of samples having different component compositions shown in Table 1.

As shown in Table 1, the specific composition of Sample C-5 was, as weight percent, 12% Cr, 4.8% Co,
Al 5.6%, Ti 2%, W 8%, Ta 5%, Mo0
%, Nb1%, Ir0%, Hf1%, Y0.2%, C
The composition contained 0.05%, 0.02% of B, and 0.02% of Zr, and the balance was Ni-based and unavoidable impurities.

As shown in Table 1, the specific composition of Sample C-6 was as follows: Cr 12%, Co 4.8%,
Al 5.6%, Ti 2%, W 5%, Ta 5%, Mo4
%, Nb1%, Ir0%, Hf1%, Y0.2%, C
The composition contained 0.05%, 0.02% of B, and 0.02% of Zr, and the balance was Ni-based and unavoidable impurities.

Further, using the above-mentioned Ni-base heat-resistant superalloy material, a test piece subjected to the same treatment as in Example 1 was produced.

For the test piece obtained in this comparative example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, in sample C-5, the life in creep rupture characteristics was 223 hours, the elongation was 24%, the corrosion weight loss was 0.74 mg / cm ² , and the oxidation weight gain was 0.37 mg / c.
It was m ^2. Sample C-6 has a creep rupture life of 216 hours, an elongation of 22%, a weight loss of corrosion of 1.09 mg / cm ² , and a weight gain of oxidation of 0.44 mg / cm ² .
It was ² . The test conditions are the same as in Example 1.

Comparative Example 4 In this comparative example, C-7 and C-8 were used as two kinds of samples having different component compositions shown in Table 1.

As shown in Table 1, the specific composition of Sample C-7 was, as weight percent, 12% Cr, 4.8% Co,
Al 5.6%, Ti 2%, W 2%, Ta 5%, MoO.
8%, Nb1%, Ir0%, Hf1%, Y0.2%, C
The composition contained 0.05%, 0.02% of B, and 0.02% of Zr, and the balance was Ni-based and unavoidable impurities.

As shown in Table 1, the specific composition of Sample C-8 was as follows: Cr 12%, Co 4.8%,
Al 5.6%, Ti 2%, W 9%, Ta 5%, MoO.
8%, Nb1%, Ir0%, Hf1%, Y0.2%, C
The composition contained 0.05%, 0.02% of B, and 0.02% of Zr, and the balance was Ni-based and unavoidable impurities.

Using the above-mentioned Ni-base heat-resistant superalloy material, test pieces subjected to the same treatment as in Example 1 were produced.

For the test piece obtained in this comparative example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, in Sample C-7, the life in creep rupture characteristics was 216 hours, the elongation was 16%, the weight loss in corrosion was 0.72 mg / cm ² , and the weight gain in oxidation was 0.43 mg / c.
It was m ^2. Sample C-8 had a creep rupture life of 210 hours, an elongation of 27%, a weight loss of corrosion of 1.25 mg / cm ² , and a weight gain of oxidation of 0.45 mg / cm 2.
It was ² . The test conditions are the same as in Example 1.

Comparative Example 5 In this comparative example, C-9 and C-10 were used as two kinds of samples having different component compositions shown in Table 1.

As shown in Table 1, the specific composition of Sample C-9 was as follows: Cr 12%, Co 4.8%,
Al 5.6%, Ti 2%, W 8%, Ta 2%, MoO.
8%, Nb1%, Ir0%, Hf1%, Y0.2%, C
The composition contained 0.05%, 0.02% of B, and 0.02% of Zr, and the balance was Ni-based and unavoidable impurities.

As shown in Table 1, the specific composition of Sample C-10 was as follows: Cr 12%, Co 4.8 by weight.
%, Al 5.6%, Ti 2%, W 5%, Ta 9%, Mo
0.8%, Nb1%, Ir0%, Hf1%, Y0.2
%, 0.05% of C, 0.02% of B, and 0.02% of Zr, with the balance being Ni-based and unavoidable impurities.

Using the above-mentioned Ni-base heat-resistant superalloy material, a test piece subjected to the same treatment as in Example 1 was produced.

For the test piece obtained in this comparative example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, in Sample C-9, the life in creep rupture characteristics was 219 hours, the elongation was 20%, the corrosion weight loss was 0.68 mg / cm ² , and the oxidation weight gain was 0.50 mg / c.
It was m ^2. Sample C-10 had a life of 213 hours in creep rupture characteristics, an elongation of 18%, a weight loss of corrosion of 0.69 mg / cm ² , and a weight gain of oxidation of 0.50 mg / c.
It was m ^2. The test conditions are the same as in Example 1.

Comparative Example 6 In this comparative example, C-11 and C-12 were used as two kinds of samples having different component compositions shown in Table 1.

The specific composition of Sample C-11 is, as shown in Table 1, 12% by weight of Cr and 4.8% of Co by weight percent.
%, Al 5.6%, Ti 2%, W 6%, Ta 7%, Mo
2%, Nb2.5%, Ir0%, Hf1%, Y0.2
%, 0.05% of C, 0.02% of B, and 0.02% of Zr, with the balance being Ni-based and unavoidable impurities.

As shown in Table 1, the specific composition of Sample C-12 is, as weight percent, Cr 12% and Co 4.8.
%, Al 5.6%, Ti 2%, W 9%, Ta 10%, M
o3%, Nb2%, Ir0%, Hf1%, Y0.2%,
Containing C0.05%, B0.02%, Zr0.02%,
The balance was Ni-based and unavoidable impurities.

Further, a test piece which was subjected to the same treatment as in Example 1 was produced using the above-mentioned Ni-base heat-resistant superalloy material.

For the test piece obtained in this comparative example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, Sample C-11 had a life of 221 hours in creep rupture characteristics, an elongation of 21%, a weight loss of corrosion of 0.64 mg / cm ² , and a weight gain of oxidation of 0.35 mg / cm ² .
cm ² . Sample C-12 had a creep rupture life of 202 hours, an elongation of 18%, a weight loss of corrosion of 0.70 mg / cm ² , and a weight gain of oxidation of 0.36 mg / cm ² .
cm ² . The test conditions are the same as in Example 1.

Comparative Example 7 In this comparative example, C-13, C-14 and C-15 were used as three kinds of samples having different component compositions shown in Table 1.

As shown in Table 1, the specific composition of Sample C-13 was, as weight percent, Cr 12% and Co 4.8.
%, Al 3.5%, Ti 0%, W 7%, Ta 5%, Mo
2%, Nb1%, Ir0%, Hf1%, Y0.2%, C
The composition contained 0.05%, 0.02% of B, and 0.02% of Zr, and the balance was Ni-based and unavoidable impurities.

As shown in Table 1, the specific composition of Sample C-14 was as follows: Cr 12%, Co 4.8 by weight.
%, Al 10%, Ti 5%, W 7%, Ta 5%, Mo
0.8%, Nb1%, Ir0%, Hf1%, Y0.2
%, 0.05% of C, 0.02% of B, and 0.02% of Zr, with the balance being Ni-based and unavoidable impurities.

As shown in Table 1, the specific composition of Sample C-15 was as follows: Cr 12%, Co 4.8 by weight.
%, Al 8%, Ti 8%, W 7%, Ta 5%, MoO.
8%, Nb1%, Ir0%, Hf1%, Y0.2%, C
It contained 0.05%, B0.02, and Zr0.02%, with the balance being Ni-based and unavoidable impurities.

[0110] Using the above Ni-based heat-resistant superalloy material, a test piece subjected to the same treatment as in Example 1 was produced.

For the test piece obtained in this comparative example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, Sample C-13 had a life of 201 hours in creep rupture characteristics, an elongation of 20%, a weight loss of corrosion of 0.62 mg / cm ² , and a weight gain of oxidation of 3.90 mg / cm ² .
cm ² . Sample C-14 has a creep rupture life of 198 hours, an elongation of 11%, a weight loss of corrosion of 0.63 mg / cm ² , and a weight gain of oxidation of 0.22 mg / cm 2.
It was ² . Sample C-15 had a creep rupture life of 184 hours, an elongation of 22%, a weight loss of corrosion of 0.41 mg / cm ² , and a weight gain of oxidation of 0.28 mg / cm ² .
It was ² . The test conditions are the same as in Example 1.

Comparative Example 8 In this comparative example, C-16 was used as a sample shown in Table 1.

As shown in Table 1, the specific composition of Sample C-16 was as follows: Cr 12%, Co 6%, A
l5.6%, Ti 2%, W 7%, Ta 5%, Mo 0.8
%, Nb1%, Ir4%, Hf1%, Y0.2%, C
The composition contained 0.05%, 0.02% of B, and 0.02% of Zr, and the balance was Ni-based and unavoidable impurities.

[0114] Using the above Ni-based heat-resistant superalloy material, a test piece subjected to the same treatment as in Example 1 was produced.

For the test piece obtained in this comparative example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, in Sample C-16, the life in creep rupture characteristics was 186 hours, the elongation was 20%, the corrosion weight loss was 1.18 mg / cm ² , and the oxidation weight gain was 0.54 mg / cm ² .
cm ² . The test conditions are the same as in Example 1.

Comparative Example 9 In this comparative example, C-17 and C-18 were used as two kinds of samples having different component compositions shown in Table 1.

As shown in Table 1, the specific composition of Sample C-17 was as follows: Cr 12%, Co 6%, A
l5.6%, Ti 2%, W 7%, Ta 5%, Mo 0.8
%, Nb 4%, Ir 0%, Hf 0%, Y 0%, C0.0
5%, B 0.02%, Zr 0.02%, the balance being N
i-group and unavoidable impurities.

As shown in Table 1, the specific composition of Sample C-18 was, as weight percent, 12% Cr, 6% Co,
l5.6%, Ti 2%, W 7%, Ta 5%, Mo 0.8
%, Nb1%, Ir0%, Hf2.5%, Y0.5%,
Containing C0.05%, B0.02%, Zr0.02%,
The balance was Ni-based and unavoidable impurities.

Further, a test piece subjected to the same treatment as in Example 1 was produced using the above-mentioned Ni-base heat-resistant superalloy material.

For the test piece obtained in this comparative example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, Sample C-17 had a creep rupture life of 214 hours, an elongation of 24%, a weight loss of corrosion of 1.64 mg / cm ² , and a weight gain of oxidation of 2.55 mg / cm ² .
cm ² . Sample C-18 had a creep rupture life of 203 hours, an elongation of 23%, a corrosion weight loss of 1.28 mg / cm ² , and an oxidation weight gain of 1.88 mg / cm ² .
cm ² . The test conditions are the same as in Example 1.

Comparative Example 10 In this comparative example, C-19 was used as a sample shown in Table 1.

As shown in Table 1, the specific composition of Sample C-19 was as follows: Cr 12%, Co 6%, A
l5.6%, Ti 2%, W 7%, Ta 5%, Mo 0.8
%, Nb1%, Ir0%, Hf1%, Y0.2%, C
0.4%, B0.05%, Zr0.08%, and the balance was Ni-based and unavoidable impurities.

Further, using the above-mentioned Ni-base heat-resistant superalloy material, a test piece subjected to the same treatment as in Example 1 was produced.

For the test piece obtained in this comparative example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, Sample C-16 had a creep rupture life of 222 hours, an elongation of 20%, a corrosion weight loss of 0.68 mg / cm ² , and an oxidation weight gain of 0.56 mg / cm ² .
cm ² . The test conditions are the same as in Example 1.

Conventional Example 1 In this conventional example, a sample CM247LC shown in Table 1 was used.

The specific composition of the sample CM247LC is shown in Table 1.
8.3% Cr, Co
9.4%, Al 5.7%, Ti 0.7%, W 9.3%,
Ta 3.2%, Mo 0.5%, Nb 0%, Ir 0%, H
f1.4%, Y0%, C0.07%, B0.017%,
Zr was contained 0.02%, and the balance was Ni-based and unavoidable impurities.

After the above-mentioned Ni-base heat-resistant superalloy material was melted, it was cast into a directionally solidified columnar crystal by a high-speed solidification method, and heated at 1230 ° C. in an inert atmosphere. Thereafter, a solution treatment was performed at the above-mentioned temperature for 2 hours, then, an aging treatment was performed at 1080 ° C. for 4 hours, and further, an aging treatment was performed at 870 ° C. for 24 hours.

For the test piece obtained in this conventional example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, the sample CM247LC had a life of 156 hours in creep rupture characteristics, an elongation of 26%,
Corrosion weight loss is 3.10 mg / cm ² , oxidation weight gain is 0.42
mg / cm ² . The test conditions are the same as in Example 1.

Conventional Example 2 In this conventional example, a sample CM186LC shown in Table 1 was used.

Table 1 shows the specific composition of the sample CM186LC.
6.8% Cr, Co
9.2%, Al 5.6%, Ti 0.7%, W 8.5%,
Ta 3.2%, Mo 0.5%, Nb 0%, Ir 0%, H
f1.4%, Y0%, C0.071%, B0.015
%, Zr 0.006%, and the balance was Ni-based and unavoidable impurities.

Using the above-mentioned Ni-base heat-resistant superalloy material, the same treatment as in Conventional Example 1 was performed to produce a test piece.

For the test piece obtained in this conventional example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, the sample CM186LC had a life of 267 hours in creep rupture characteristics, an elongation of 19%,
Corrosion weight loss 1.20 mg / cm ² , oxidation weight loss 0.68
mg / cm ² . The test conditions are the same as in Example 1.

Conventional Example 3 In this conventional example, single crystal CMSX-2 was used as a sample shown in Table 1.

As shown in Table 1, the composition of the specific sample CMSX-2 was as follows: Cr 7.9%, Co
4.6%, Al 5.6%, Ti 1%, W7.9%, Ta
6%, Mo 0.6%, Nb 0%, Ir 0%, Hf 0.0
04%, Y0%, C0.0014%, B0.002%,
It contained 0.001% of Zr, and the balance was Ni-based and unavoidable impurities.

Using the Ni-base heat-resistant superalloy material described above, the treatments shown in Table 2 were performed to produce test pieces.

For the test piece obtained in this conventional example,
A creep rupture test, a high temperature corrosion resistance test, and an oxidation resistance test were performed. As a result, for sample CMSX-2,
Creep rupture life is 313 hours, elongation is 2
3%, the corrosion weight loss is 2.90mg / cm ^2, oxidized amount was 0.56 mg / cm ^2. The test conditions are the same as in Example 1.

The following has been found from the above Examples, Comparative Examples and Conventional Examples.

First, Al and Ti will be described. In Sample C-15 of Comparative Example 7 in which the contents of both elements of Al and Ti were high, a relatively large amount of undissolved γ 'phase and eutectic γ' phase remained after the heat treatment, and the creep rupture life was longer than that of the Example. 1-4
Was relatively shorter than the present invention. A
Sample C-13 of Comparative Example 7, which had a low l content, had the largest amount of oxidation increase, had a shorter creep rupture life than the present invention in Examples 1 to 4, and had a lower oxidation resistance.

Regarding Nb, the content was 4% and 0.5 to 0.5%.
Sample C-17 of Comparative Example 9, which is out of the claim range of 2.5%
In particular, high-temperature corrosion resistance and oxidation resistance were reduced.

Regarding Ir, in Examples 1 to 4,
Examples 2 and 3 in which the content of r is 2.5% show the best creep rupture life. On the contrary, Samples C-16 to C-19 of Comparative Examples 8 and 9 in which the content of Ir is out of the range of 1.5 to 3% are as follows:
The strength and ductility were reduced, and the creep rupture life was also reduced.

A description will be given of W, Mo, and Ta. W, M
In Sample C-12 of Comparative Example 6 having a large content of o and Ta, an α- (W, Mo) phase which adversely affects the high-temperature strength was precipitated,
Furthermore, the residual amount of the eutectic γ 'phase remaining by the heat treatment increased, and the creep rupture life decreased. Sample C-, which has a high content of at least one of these three elements
6, C-8, C-10, and C-11 each had a relatively shorter creep rupture life than the present invention in Examples 1 to 4. In addition, even when the above three elements were within the specified ranges, the creep rupture life of Sample C-11 and Sample C-12 of Comparative Example 6, in which the total amount of addition exceeded 14%, was reduced.

Regarding Cr and Co, in Samples C-2 and C-4 of Comparative Examples 1 and 2 having a large Cr and Co content,
Since the σ phase was precipitated and the amount of the undissolved γ ′ phase increased, the creep rupture life was shorter than that of the present invention in Examples 1 to 4.

A description will be given of Hf and Y. In Sample C-17 of Comparative Example 9, which did not contain Hf and Y, peeling of the protective film occurred, and high-temperature corrosion resistance and oxidation resistance were reduced.
Sample C-18 of Comparative Example 9 in which the content of Y is excessive.
In Y, the inward diffusion of oxygen was promoted by Y, the amount of oxidation increased, and the oxidation resistance was lowered. In Sample C-18 of Comparative Example 9 in which the Hf content was excessive, an undissolved γ 'phase remained after the heat treatment, and the creep rupture life was reduced.

Regarding C, B and Zr, the sample C-19 of Comparative Example 10 containing excessive amounts had a reduced ductility and a reduced creep rupture life.

In contrast to the heat-resistant alloys of Comparative Examples 1 to 10, Examples 1 to 4 according to the present invention
Al, Ti, W, Mo, Ta, Nb, Ir, Hf, Y,
Since the elements C, B, and Zr were added in a well-balanced manner based on the optimal content, total amount, and ratio based on the chemical composition of the present invention, the desired form of the γ 'phase, Nb
₃ Al phase and Ir ₃ Ti phase are precipitated, and the harmful embrittlement phase α- (W, Mo) phase and σ phase are not precipitated.
Both the creep rupture life was longer and the high temperature strength was superior to the comparative example and the conventional example. Further, Examples 1 to 4 in the present invention have high-temperature strength corresponding to the first generation Ni-based single crystal alloy CMSX-2. Also,
It has been confirmed that these alloys according to the present invention can reduce both the corrosion weight loss and the oxidation weight gain, and are excellent in high-temperature corrosion resistance and oxidation resistance.

Accordingly, it has been clarified that the alloy of the present invention has excellent properties in all of high-temperature strength, high-temperature corrosion resistance and oxidation resistance as compared with the conventional alloy.

From the above, the alloy of the present invention can be sufficiently applied to industrial gas turbine parts requiring high-temperature corrosion resistance, which has been conventionally difficult to use. In this case, in addition to high-temperature strength and oxidation resistance, In addition, the advantages of high temperature corrosion resistance can be maximized. That is, high efficiency and long-term operation of the industrial gas turbine have become possible, and the operating efficiency of the gas turbine has been greatly improved.

Other Examples Although the Ni-based heat-resistant superalloy of the present invention is manufactured by the manufacturing method shown in Table 2, the manufacturing method of the Ni-based unidirectionally solidified superalloy according to the present invention is described in this example. It is not limited. For example, the invention described in claim 4 may be applied. That is, the manufacturing method according to the fourth aspect of the present invention employs the method for manufacturing a Ni-base heat-resistant superalloy disclosed in Japanese Patent Application Laid-Open No. 6-293945. And, the method comprises the steps of:
The heat-resistant superalloy is manufactured by continuously performing a solution treatment and a subsequent aging treatment while maintaining the aging treatment temperature or higher.

Specifically, N having the chemical composition of the present invention
After melting the i-base heat-resistant superalloy material,
A base directionally solidified heat-resistant superalloy is formed, and the directionally solidified heat-resistant superalloy is subjected to a solution treatment at a temperature of 1200 ° C. to 1250 ° C., and then cooled at a cooling rate of 300 ° C./hour or more from that temperature.
It is preferable to cool to a temperature of 050 ° C. to 1150 ° C. and perform aging treatment while maintaining the cooled temperature.

The Ni-based unidirectionally solidified heat-resistant superalloy produced in this manner has a γ ′ phase, an Ir ₃ Ti phase and an N ₃ Ti phase with a sufficient volume ratio desired to further enhance the high-temperature strength characteristics in the γ matrix.
This has the advantage that a b ₃ Al phase is precipitated, and a microstructure in which the cubic γ ′ phase, which is the optimum shape for the γ ′ phase, is regularly arranged in a lattice is obtained.

[0151]

As described above, the Ni-base heat-resistant superalloy of the present invention has excellent creep rupture life, elongation and high-temperature corrosion resistance equivalent to existing first-generation Ni-base single crystal superalloys,
Has both oxidation resistance. As a result, as components such as high-temperature high-efficiency gas turbines and blades of industrial gas turbines that have been difficult to apply in the long run, they can be operated under high creep stress and in severe high-temperature corrosion / oxidation environments. This greatly contributes to the improvement of the efficiency.

[Brief description of the drawings]

FIG. 1 shows Examples 1-4, Comparative Examples 1-10 and Conventional Examples 1
3 is a graph for explaining the rupture life of the result of the creep rupture test of No. 3.

FIG. 2 Examples 1 to 4, Comparative Examples 1 to 10, and Conventional Examples 1 to
3 is a graph illustrating the elongation at break of the results of the creep rupture test of Example 3.

FIG. 3 Examples 1 to 4, Comparative Examples 1 to 10, and Conventional Examples 1 to
3 is a graph for explaining the corrosion weight loss of the high-temperature corrosion resistance test result of No. 3.

FIG. 4 Examples 1 to 4, Comparative Examples 1 to 10, and Conventional Examples 1 to
3 is a graph illustrating the increase in oxidized mass in the results of the oxidation resistance test of Example 3.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C22F 1/00 691 C22F 1/00 691B 691C 691Z 1/10 1/10 H

Claims (9)

[Claims] 1. A weight percentage of Cr: 8 to 14%, Co: 7
-12%, Al: 5-8%, Ti: 1-4%, W: 3-
8%, Ta: 3 to 8%, Mo: 0.5 to 2%, Nb:
0.5 to 2.5%, Ir: 1.5 to 3%, C: 0.05
0.2%, B: 0.01-0.03%, Zr: 0.0
2 to 0.05%, the balance consisting of Ni and unavoidable impurities, and 6% ≦ Al + Ti, 2 ≦ Al / Ti,
A Ni-base heat-resistant superalloy, wherein W + Ta + Mo ≦ 14%. 2. Cr: 8 to 14%, Co: 7 by weight%
-12%, Al: 5-8%, Ti: 1-4%, W: 3-
8%, Ta: 3 to 8%, Mo: 0.5 to 2%, Nb:
0.5 to 2.5%, Ir: 1.5 to 3%, C: 0.05
0.2%, B: 0.01-0.03%, Zr: 0.0
2 to 0.05%, the balance consisting of Ni and unavoidable impurities, and 6% ≦ Al + Ti, 2 ≦ Al / Ti,
A Ni-based heat-resistant superalloy characterized by being unidirectionally solidified from a Ni-based heat-resistant superalloy material in which W + Ta + Mo ≦ 14%. 3. Ni, Cr, Co, Al, Ti, W, T
After a molten material containing a, Mo, Nb, Ir, C, B, and Zr is unidirectionally solidified, the material is heated to 1200 ° C. to 1250 ° C. in a vacuum or an inert atmosphere.
After solution treatment for more than an hour, quenched, then 1050 ° C
A method for producing a Ni-base heat-resistant superalloy, comprising performing aging treatment at 〜1150 ° C. for 4 hours or more. 4. The method for producing a Ni-base heat-resistant superalloy according to claim 3, wherein the solution treatment and the subsequent aging treatment are performed at a high temperature successively at a high temperature of 1200 ° C.
Aging treatment from temperature range of 1250 ° C to 1250 ° C
The cooling rate to the temperature range of 0 ° C. is set to 300 ° C./hour or more, and after maintaining at the aging temperature range for 2 hours or more, rapid cooling is performed, and then aging is performed again at 1050 ° C. to 1150 ° C. for 4 hours or more. A method for producing a Ni-based heat-resistant superalloy, characterized in that: 5. Cr: 8 to 14%, Co: 7% by weight
-12%, Al: 5-8%, Ti: 1-4%, W: 3-
8%, Ta: 3 to 8%, Mo: 0.5 to 2%, Nb:
0.5 to 2.5%, Ir: 1.5 to 3%, Hf: 0.5
~ 2%, Y: 0.15 ~ 0.3%, C: 0.05 ~ 0.
2%, B: 0.01-0.03%, Zr: 0.02-
0.05%, the balance being Ni and unavoidable impurities, and 6% ≦ Al + Ti, 2 ≦ Al / Ti, W +
A Ni-based heat-resistant superalloy, wherein Ta + Mo ≦ 14%. 6. Cr: 8 to 14%, Co: 7% by weight
-12%, Al: 5-8%, Ti: 1-4%, W: 3-
8%, Ta: 3 to 8%, Mo: 0.5 to 2%, Nb:
0.5 to 2.5%, Ir: 1.5 to 3%, Hf: 0.5
~ 2%, Y: 0.15 ~ 0.3%, C: 0.05 ~ 0.
2%, B: 0.01-0.03%, Zr: 0.02-
0.05%, the balance being Ni and unavoidable impurities, and 6% ≦ Al + Ti, 2 ≦ Al / Ti, W +
A Ni-based heat-resistant superalloy obtained by unidirectionally solidifying a Ni-based heat-resistant superalloy material satisfying Ta + Mo ≦ 14%. 7. Ni, Cr, Co, Al, Ti, W, T
After the molten material containing a, Mo, Nb, Ir, Hf, Y, C, B, and Zr is unidirectionally solidified, the material is heated to 1200 ° C. to 1250 ° C. in a vacuum or an inert atmosphere, and the temperature range is the same. Solution treatment for 2 hours or more and then quenched.
A method for producing a Ni-base heat-resistant superalloy, comprising aging at 50C to 1150C for 4 hours or more. 8. The method for producing a Ni-base heat-resistant superalloy according to claim 7, wherein the solution treatment and the subsequent aging treatment are continuously performed at a high temperature at a high temperature of 1200 ° C.
Aging treatment from temperature range of 1250 ° C to 1250 ° C
The cooling rate to the temperature range of 0 ° C. is set to 300 ° C./hour or more, and after maintaining at the aging temperature range for 2 hours or more, rapid cooling is performed, and then aging is performed again at 1050 ° C. to 1150 ° C. for 4 hours or more. A method for producing a Ni-based heat-resistant superalloy, characterized in that: 9. A Ni-base heat-resistant superalloy component comprising a turbine blade and other gas turbine engine components made of the Ni-base heat-resistant superalloy according to claim 1, 2, or 5.