JP2001071410A - Composite material and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance oxidation resistance and heat resistance without use of an anti-oxidation coating by joining an alloy and a ceramic dispersed/reinforced alloy together through an alloy foil. SOLUTION: First alloy powder 3 and ceramic powder 4 are compounded by a mechanical alloying treatment to obtain composite powder 5. Further, the composite powder 5 and an alloy 7 not containing a ceramic with an alloy foil 6 as an insert material sandwiched in between are sealed in a metallic pipe 8 and are subjected to a HIP method to obtain a monolithic composite material 9. In addition, the composite material 9 is stable even in the high temperature region because ceramic particles dispersed in a metallic matrix are not dissolved as solids in the metallic matrix and therefore, is a highly reliable material in terms of oxidation resistance and heat resistance. Thus a stress generated by the difference in thermal expansion between the alloy 7 and a ceramic dispersed/reinforced alloy is absorbed by the alloy foil 6, so that the joined part is not separated and the composite material 9 obtained shows an outstanding joining strength.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite material comprising an alloy and a ceramic dispersion-strengthened alloy and a method for producing the same, and more particularly to a composite material suitable as a material for high-temperature components such as a shroud segment for a gas turbine whose temperature is increasing. And a method of manufacturing the same.

[0002]

2. Description of the Related Art In a power generation gas turbine, the higher the gas temperature at the gas turbine combustor outlet, the higher the power generation efficiency.

[0003] However, such a high temperature is an extremely severe environment for components such as moving and stationary blades and a combustor that constitute a gas turbine, and there is a problem that the strength of these components is reduced, and corrosion and oxidation are generated. It has become.

At present, moving and stationary blades constituting a gas turbine,
Ni-base superalloys applied to components such as combustors are γ '
Although the precipitated phase is used as a strengthening factor, the usable temperature of the Ni-base superalloy is limited to 1000 ° C. or lower because the γ ′ phase can be stably present at 1000 ° C. or lower.

[0005] Therefore, development of an oxide dispersion-strengthened (ODS) alloy having excellent strength up to a high temperature close to the melting point of the matrix metal by dispersing and introducing ceramic particles that are stable even at a high temperature into the alloy.・ Research is being considered.

Taking a shroud segment for a gas turbine as an example, in a current 1100 ° C. to 1300 ° C. class gas turbine, the first stage shroud segment base material temperature is about 8
The temperature was close to 00 ° C., and the conventional Fe-based alloy had problems in oxidation resistance and heat resistance.

A gas turbine shroud segment made of a Ni-base cast alloy having excellent heat resistance has been disclosed in Japanese Patent Application No. 4-202313.

FIG. 13 shows a method of manufacturing a shroud segment for a gas turbine according to the prior art described in the above publication. The invention described in the above publication is characterized by Ni:
40%, Cr: 20-35%, C: 0.15-0.35
%, Si: 0.2 to 2%, Mn: 0.4 to 1.5%, and a cast base 1 for a shroud segment having a basic composition consisting of the balance of Fe and having excellent heat resistance by machining. This is for producing a shroud segment 2 for a gas turbine.

[0009]

However, high-temperature components made of a Ni-base cast alloy have a problem in oxidation resistance. As a result of performing a high-temperature oxidation test on a representative Ni-based cast alloy in the air, it has been clarified that the base material surface is greatly reduced in thickness by oxidation.

For example, when the shroud segment surface is reduced in thickness, the output of the gas turbine is reduced.
It is not preferable to apply a base material having high temperature oxidation and high temperature corrosion, such as a base cast alloy, to the gas turbine shroud segment.

At present, the application of an oxidation-resistant coating is also being studied. However, when the shroud segment comes into contact with the moving blade during operation of the actual machine, the coating material may be peeled off or chipped. Not preferred.

In the future, it is conceivable to raise the operating temperature in order to increase the efficiency of the gas turbine, and it is expected that the temperature of the base material will further increase. Many Ni-based cast alloys use the γ 'precipitated phase as a strengthening factor. However, when the temperature becomes 900 ° C. or higher, the γ' phase cannot be stably present, and it is considered that a remarkable decrease in strength occurs. Therefore, it is difficult to apply a Ni-based casting alloy to future high-temperature components for gas turbines, and it is conceivable to apply the ODS alloy as described above.

However, since the ODS alloy is very expensive, it is economically difficult to manufacture a high-temperature component for a gas turbine using the ODS alloy alone. In addition, it is conceivable to produce parts by combining inexpensive ODS alloys that do not contain ceramics by welding or the like. However, joining such as fusion with the material, such as electron beam welding (EB) welding or TIG welding, is considered. In such a case, the metal oxide and the matrix metal, which are reinforcing factors, are separated from each other at the joint, so that the strength of the joint significantly decreases.

An alloy containing no ceramic and an ODS
Alloys have poor adhesion due to the large difference in coefficient of thermal expansion.
Cracks may occur when used at high temperatures.

The present invention has been made in order to solve such problems, and relates to a composite material which does not require an oxidation-resistant coating and has excellent oxidation resistance and heat resistance, and a method for producing the same. In particular, an object of the present invention is to provide a composite material for a high-temperature component such as a shroud segment for a gas turbine, which has excellent high-temperature characteristics, and a method for producing the same.

[0016]

The composite material according to the present invention is characterized in that the alloy and the ceramic dispersion strengthened alloy are joined via an alloy foil.

At this time, the ceramic dispersion strengthened alloy is A
It preferably contains at least one of l ₂ O ₃ and Y ₂ O ₃ . Further, it is preferable that the ceramic dispersion strengthened alloy is mainly made of Fe or Ni.

Further, it is preferable that the alloy foil used in the present invention is mainly composed of any one of Ni, Cu, Al and Au.

The method for producing a composite material according to the present invention comprises the steps of: preparing a composite powder by compounding an alloy powder for composite use and a ceramic powder by mechanical alloying; and placing the alloy and the composite powder in a metal tube. A step of disposing them via an alloy foil and integrating them by a hot isostatic pressing (HIP) method.

Further, the method for producing a composite material according to the present invention comprises the steps of preparing a composite powder by compounding an alloy powder for composite use and a ceramic powder by a mechanical alloying treatment, and placing the alloy powder and the composite powder in a metal tube. Is set through an alloy foil, and H
And a step of integrating by an IP method (hot isostatic pressing).

At this time, the alloy powder and the composite powder provided via the alloy foil are preferably provided in layers in a direction parallel, perpendicular or circumferential to the axial direction of the metal tube.

Further, the method for producing a composite material according to the present invention comprises a step of preparing a composite powder by compounding an alloy powder for composite and a ceramic powder by mechanical alloying, and a step of preparing the composite powder in a metal container. And vacuum-encapsulating the powder and the alloy via an alloy foil, and integrating them using a hot extrusion method.

At this time, it is preferable that the alloy powder and the composite powder, which are vacuum-sealed through the alloy foil, are inserted in layers in a direction parallel to, perpendicular to, or in the outer peripheral direction of the metal container in the extrusion direction.

In the method for producing a composite material according to the present invention, the ceramic powder is mainly composed of Al ₂ O ₃ and Y.
It is preferable that it be made of at least one oxide selected from ₂ O _{3 and the} like.

It is preferable to use an alloy powder mainly composed of Fe or Ni as the composite alloy powder.

Further, alloy foils mainly include Ni,
It is preferable to use any one of Cu, Al and Au.

The composite material of the present invention or the method for producing a composite material as described above is preferably used for producing, for example, a shroud segment for a gas turbine and a moving / static blade for a gas turbine.

In the composite material of the present invention, since the alloy and the ceramic dispersion strengthened alloy are joined via an alloy foil,
The alloy foil absorbs the stress generated due to the difference in thermal expansion between the alloy and the ceramic dispersion strengthened alloy, and does not cause peeling or the like at the joint, and has excellent joint strength. Further, in the composite material of the present invention, since the ceramic particles do not form a solid solution in the metal matrix, they are very stable even in a high temperature region,
It has excellent oxidation resistance and heat resistance. Furthermore, the composite material of the present invention is composed of an alloy and a ceramic dispersion strengthened alloy, and can be manufactured at a lower cost than a conventional material composed of only a ceramic dispersion strengthened alloy.

The ceramic dispersion-strengthened alloy used for such a composite material has an A which does not form a solid solution
By containing an oxide ceramic such as l ₂ O ₃ or Y ₂ O ₃ , sufficient high-temperature strength can be maintained even at an extremely high temperature near the melting temperature, and oxidation resistance and heat resistance can be improved.

Further, by making the ceramic dispersion strengthened alloy mainly composed of Fe, the oxidation resistance at high temperatures can be improved and the cost can be reduced. In addition, when the ceramic dispersion strengthened alloy is mainly composed of Ni, the high-temperature strength can be improved. Therefore,
By properly using these materials, it is possible to provide a composite material that satisfies the use environment and required characteristics of the device.

As an alloy foil used for such a composite material, Ni, Cu, Al or A having excellent deformability is mainly used.
By using an alloy made of u, it is possible to fill the micro unevenness of the joint and to enhance the adhesion of the joint, thereby improving the joint strength of the composite material.

In the method for producing a composite material of the present invention, for example, an alloy and a composite powder are placed in a metal tube via an alloy foil,
Since the integration is performed by the IP method (hot isostatic pressing), the joining strength between the composite powder containing ceramic and the alloy not containing ceramic can be improved without the necessity of welding accompanied by melting of the material. In addition, by using the alloy foil having excellent deformability, the micro unevenness of the portion to be joined is filled, so that a composite material with further improved adhesion at the joint can be provided.

In the method for producing a composite material of the present invention, for example, an alloy powder and a composite powder are placed in a metal tube via an alloy foil and integrated by a hot isostatic pressing (HIP) method. Therefore, the bonding strength between the composite powder containing ceramic and the alloy not containing ceramic can be improved without the need for welding or the like. In addition, by using an alloy foil having excellent deformability, the micro unevenness of the portion to be joined is filled, so that it is possible to provide a composite material in which the adhesion of the joining portion is further improved.

Further, in the method for producing a composite material according to the present invention, the alloy powder and the composite powder are vacuum-enclosed in a metal container through an alloy foil, and are integrated by hot extrusion to thereby form a HIP method. (Hot isostatic pressing) The composite material can be produced more economically than the production method using hot isostatic pressing.

In the method for producing a composite material according to the present invention, Al ₂ O ₃ , which does not form a solid solution in the metal matrix,
By using an oxide such as Y ₂ O ₃ as the ceramic powder, sufficient high-temperature strength can be maintained even at an extremely high temperature near the melting temperature.

Further, by using a composite alloy powder mainly composed of Fe, the oxidation resistance at high temperatures can be improved and the cost can be reduced. Further, by using a composite alloy powder mainly composed of Ni, the high-temperature strength can be improved. Therefore, by appropriately using these materials, it is possible to provide a composite material that satisfies the use environment and required characteristics of the device.

In the method for producing a composite material of the present invention,
Mainly Ni, Cu, Al with excellent deformability as alloy foil
Alternatively, by using an alloy made of Au, it is possible to fill the micro unevenness of the portion to be bonded, improve the adhesion of the bonded portion, and produce a composite material having excellent bonding strength.

By producing a shroud segment for a gas turbine or the like using the composite material or the method for producing a composite material of the present invention, a material having excellent oxidation resistance and heat resistance can be produced. Further, in the present invention, since welding or the like accompanied by melting of the material is not required, it is possible to suppress a decrease in strength at a joint between an alloy containing ceramic and an alloy not containing ceramic. Further, since the alloy foil as the insert material can be easily deformed, it is possible to fill the micro unevenness of the portion to be joined, and to produce a shroud segment for a gas turbine having excellent adhesion at the joint.

[0039]

Embodiments of the present invention will be described below.

[First Embodiment] In the present embodiment, an example of a method of integrating an alloy and a composite powder using an alloy foil will be described.

FIG. 1 shows a method for manufacturing a composite material according to this embodiment.

The alloy powder 3 and the ceramic powder 4 are compounded by subjecting them to a mechanical alloying treatment to produce a composite powder 5. Furthermore, after enclosing the composite powder 5 and the ceramic-free alloy 7 in a metal tube 8 via an alloy foil 6 as an insert material, a HIP method is performed.
An integrated composite material 9 is produced.

According to the present embodiment, since the ceramic particles dispersed in the metal matrix do not form a solid solution in the metal matrix, the composite material is stable even in a high temperature range and has excellent oxidation resistance and heat resistance. 9 can be provided.

Further, according to the present embodiment, since the alloy foil absorbs the stress generated due to the difference in thermal expansion between the alloy and the ceramic dispersion strengthened alloy, peeling at the joint does not occur and the joint strength is improved. An excellent composite material 9 can be provided.

Further, since the present composite material 9 does not require welding or the like accompanied by melting of the material, it is possible to suppress a decrease in the strength of the joint between the composite powder 5 and the alloy 7. Also, the alloy foil 6 as an insert material is very easily deformed,
Since the micro unevenness of the portion to be joined is filled, a composite material 9 having good adhesion at the portion to be joined can be manufactured.

[Second Embodiment] In this embodiment, an example in which an alloy powder and a composite powder are integrated via an alloy foil will be described.

FIG. 2 shows a method for manufacturing a composite material according to the present embodiment.

The composite alloy powder 3 and the ceramic powder 4
Are subjected to a mechanical alloying process to produce a composite powder 5. Furthermore, alloy foil 6 as an insert material
After the composite powder 5 and the alloy powder 10 containing no ceramic are enclosed in the metal tube 8 with the intermediary of the above, the HIP method is performed to produce an integrated composite material 9.

According to the present embodiment, since the ceramic particles dispersed in the metal matrix do not form a solid solution in the metal matrix, the composite material is stable even in a high temperature range and has excellent oxidation resistance and heat resistance. 9 can be provided.

According to the present embodiment, the alloy foil absorbs the stress generated due to the difference in thermal expansion between the alloy and the ceramic dispersion strengthened alloy. An excellent composite material 9 can be provided.

Further, since the present composite material 9 does not require welding or the like accompanied by melting of the raw material, it is possible to suppress a decrease in the strength of the joint between the composite powder 5 and the alloy 7. Also, the alloy foil 6 as an insert material is very easily deformed,
Since the micro unevenness of the portion to be joined is filled, a composite material 9 having good adhesion at the portion to be joined can be manufactured.

[Third Embodiment] In this embodiment, an example is shown in which an extrusion method is used when joining an alloy powder and a composite powder via an alloy foil.

FIG. 3 shows a method of manufacturing a composite material according to the present embodiment.

The alloy powder 3 and the ceramic powder 4 are compounded by subjecting them to a mechanical alloying process to produce a composite powder 5. Further, the composite powder 5 and the ceramic-free alloy powder 1 are inserted through an alloy foil 6 as an insert material.
After enclosing 0 in a metal container 11, an integrated composite material 9 is produced by hot extrusion.

According to the present embodiment, since the ceramic particles dispersed in the metal matrix do not form a solid solution in the metal matrix, the composite material is stable even in a high temperature range and has excellent oxidation resistance and heat resistance. 9 can be provided.

Further, according to the present embodiment, since the alloy foil absorbs the stress generated due to the difference in thermal expansion between the alloy and the ceramic dispersion strengthened alloy, the joint strength is improved without peeling at the joint. An excellent composite material 9 can be provided.

Further, since the present composite material 9 does not require welding or the like accompanied by melting of the material, it is possible to suppress a decrease in the strength of the joint between the composite powder 5 and the alloy 7. Also, the alloy foil 6 as an insert material is very easily deformed,
Since the micro unevenness of the portion to be joined is filled, a composite material 9 having good adhesion at the portion to be joined can be manufactured.

Further, by using the hot extrusion method, the composite material 9 can be manufactured at lower cost than the HIP method.

[Fourth Embodiment] In this embodiment, an outline of a method for manufacturing a shroud segment for a gas turbine using the present invention will be described.

FIG. 4 shows an example of a method for manufacturing a shroud segment for a gas turbine according to this embodiment of the present invention.

First, after the outer ring portion 12 is made of an Fe-based alloy containing no ceramic, it is placed in the metal tube 8. Further, an alloy foil 6 as an insert material is provided on the inner ring portion forming surface 12a of the outer ring portion 12.

On the other hand, the alloy powder 3 and the ceramic powder 4 are compounded by subjecting them to a mechanical alloying process to produce a composite powder 5. The composite powder 5 is sealed on the inner ring portion forming surface 13a side of the outer ring portion 12 installed in the metal tube 8 so as to form the inner ring portion 13, and the composite powder 5, the alloy foil 6, and the The outer ring portion 12 is integrated. By such a method, the shroud segment 14 for a gas turbine in which the inner ring portion 13 is made of a ceramic dispersion strengthened alloy
Is prepared.

According to the present embodiment, very excellent oxidation resistance and heat resistance are obtained by dispersing ceramic particles that are stable even at high temperatures in the inner ring portion 13 where oxidation resistance and heat resistance are required. A gas turbine shroud segment 14 can be provided. Also, instead of making the entire shroud segment from a relatively expensive ceramic dispersion strengthened alloy, the outer ring portion 12 is made of a relatively inexpensive Fe.
By making the base alloy, the gas turbine shroud segment 14 can be provided at low cost.

[Fifth Embodiment] In this embodiment, an example of a method for manufacturing a moving / static vane for a gas turbine according to the present invention will be described.

FIG. 5 shows a method for manufacturing a moving / static blade for a gas turbine according to the present embodiment.

First, after the moving and stationary blade member 15 is made of a Ni-based alloy containing no ceramic, it is placed in the metal tube 8 and the alloy foil 6 is disposed on the surface of the moving and stationary blade member 15.

On the other hand, a composite powder 5 is prepared by subjecting the alloy powder 3 and the ceramic powder 4 to a mechanical alloying process to produce a composite powder.
The composite powder 5, the alloy foil 6, and the moving and stationary blade member 15 are integrated using the HIP method. By such a method, the moving / static blade 16 for a gas turbine whose blade surface is made of a ceramic dispersion strengthened alloy is manufactured.

According to the present embodiment, excellent oxidation resistance and heat resistance can be obtained by using an alloy in which ceramic particles that are stable even at high temperatures are dispersed on the blade surface where oxidation resistance and heat resistance are required. The moving and stationary blade 16 for a gas turbine having the above configuration can be provided.

Further, instead of manufacturing the entire moving and stationary blades with a relatively expensive ceramic dispersion strengthened alloy, but manufacturing the inside of the blades with a relatively inexpensive Ni-based alloy, the moving and stationary blades for gas turbines are manufactured. The stationary blade 16 can be provided at low cost.

[0070]

[Example 1 and Comparative Example 1]
An alloy powder containing Ni as a main component to which t% Cr is added and a ceramic powder, 0.6 wt% of Y ₂ O ₃ powder, are compounded by a mechanical alloying process to produce a composite powder. It was manufactured by inserting a Fe-based alloy containing no ceramic into a metal tube with a Ni-based alloy foil as an insert material interposed therebetween, and sintering and solidifying using a HIP method.

In contrast, Comparative Example 1 was manufactured by sintering and solidifying a ceramic-free Ni-20 wt% Cr alloy powder and a ceramic-free Fe-based alloy using the HIP method.

After heat treatment was performed on each of the composite materials of Example 1 and Comparative Example 1 obtained as described above, first, in order to confirm the effectiveness of ceramic dispersion, the composite material of Example 1 was used.
Ni-20 wt% for Cr-0.6wt% Y ₂ O
_From the part of No. ₃ , for Comparative Example 1, Ni-20 wt% C
An oxidation resistance evaluation and a creep test piece were collected from the portion of r.

In the oxidation resistance evaluation test, after heating in air at 900 ° C. for 1000 hours, the amount of thinning of the test piece due to oxidation and the maximum oxidation depth were measured. The creep test was 9
The creep rupture strength at 00 ° C. was determined.

FIGS. 6 and 7 show the results of the oxidation resistance evaluation test and the creep test.

As is clear from FIGS. 6 and 7, it can be seen that Example 1 in which the ceramic powder is compounded is less affected by oxidation and has higher strength at high temperatures.

Therefore, by compounding the ceramic powder as in the present invention, it is possible to provide a composite material having functions excellent in oxidation resistance and heat resistance.

Next, with respect to the composite materials of Example 1 and Comparative Example 1, in order to confirm the adhesion of the joint, a tensile test piece was taken so that the joint was the center, and a high-temperature tensile test (test temperature) was performed. : 900 ° C). FIG. 8 shows the results of the high-temperature tensile test.

As is apparent from FIG. 8, it can be seen that Example 1 in which the alloy foil was inserted between the Fe-based alloy and the composite powder was superior in the bonding strength.

[Examples 3, 4 and Comparative Example 2] In this example, the change in the high-temperature tensile strength when the ceramic powder to be composited was changed was examined.

In the third embodiment, Ni is used as a main component and 20 w
and alloy powder was added t% Cr, a 0.6 wt% of Y ₂ O ₃ powder as the ceramic powder, after the composite by mechanical alloying treatment, by sintering and solidifying the extrusion, subjected for testing Samples were used.

In the fourth embodiment, Ni is used as a main component and 20 w
An alloy powder to which t% Cr has been added and Al ₂ O ₃ powder of 0.6 wt% as a ceramic powder are combined by a mechanical alloying process, and then sintered and solidified by extrusion to provide a test sample. Samples were used.

In Comparative Example 2, Ni was used as a main component and 20 w
An alloy powder to which t% Cr is added and a carbide powder of 0.6 wt% as a ceramic powder are combined by a mechanical alloying process, and then sintered and solidified by extrusion to obtain a test sample material. did.

The specimens of Examples 3 and 4 and Comparative Example 2 obtained as described above were subjected to a heat treatment, and thereafter, a tensile test specimen was collected and subjected to a high-temperature tensile test (test temperature: 900
° C). FIG. 9 shows the results of the tensile test.

As is clear from FIG. 9, the composite powder
Y as a ceramic powder_TwoO _ThreeOr Al_TwoO_Three
Providing suitable composite materials by using oxides such as
can do.

[Examples 6, 7 and Comparative Example 3] In this example, the change in oxidation resistance and creep rupture strength when the main component of the composite alloy powder was changed was examined.

In the sixth embodiment, Fe is used as a main component and 20 w
and alloy powder was added t% Cr, a 0.6 wt% of Y ₂ O ₃ powder as the ceramic powder, after the composite by mechanical alloying treatment, by sintering and solidifying the extrusion, subjected for testing Samples were used.

In the seventh embodiment, Ni is used as a main component and 20 w
and alloy powder was added t% Cr, a 0.6 wt% of Y ₂ O ₃ powder as the ceramic powder, after the composite by mechanical alloying treatment, by sintering and solidifying the extrusion, subjected for testing Samples were used.

Comparative Example 3 shows that Ni-
20 wt% Cr alloy powder was sintered and solidified by extrusion to obtain a test specimen.

The test materials of Examples 6 to 8 obtained as described above were subjected to heat treatment, and thereafter, test specimens were collected from each of the examples and subjected to an oxidation resistance evaluation test and a creep test. did. Oxidation resistance evaluation test: 900 ° C in air
And heated for 1000 hours, the amount of thinning of the test piece due to oxidation and the maximum oxidation depth were measured. The creep test is
The creep rupture strength at 900 ° C. was determined. 10 and 11 show the results of the oxidation resistance evaluation test and the results of the creep test.

As is clear from FIGS. 10 and 11, excellent oxidation resistance and heat resistance can be obtained by compounding the ceramic powder, but the oxidation resistance is remarkable when Fe is the main component. It can be seen that the heat resistance is remarkable when Ni is the main component. Therefore, when high-temperature strength is required, an alloy powder containing Ni as a main component is applied, and when high-temperature oxidation resistance is required, Fe powder is used.
It is preferable to use an alloy powder mainly composed of, and it is preferable to select an alloy component based on the use environment and required characteristics of equipment.

[Examples 9, 10, 11, 12 and Comparative Example 4] In the present embodiment, the high-temperature tensile strength when the alloy foil constituting the composite material was changed was examined.

In Example 9, Ni-20 wt% Cr-0.
6 wt% Y ₂ O ₃ composite powder and ceramic-free F
An e-base alloy was produced by sintering and solidifying using an HIP method with a Ni-base alloy foil as an insert material therebetween.

In Example 10, Ni-20 wt% Cr-
And 0.6wt% Y ₂ O ₃ composite powder, a Fe-based alloy containing no ceramic, through between the Cu-based alloy foil as the insert material was produced by sintering and solidifying with HIP method.

In Example 11, Ni-20 wt% Cr-
A 0.6 wt% Y ₂ O ₃ composite powder and a Fe-based alloy containing no ceramic were sintered and solidified by the HIP method with an Al-based alloy foil interposed therebetween as an insert material.

In Example 12, Ni-20 wt% Cr-
A 0.6 wt% Y ₂ O ₃ composite powder and an Fe-based alloy containing no ceramic were sintered and solidified by HIP using an Au-based alloy foil as an insert material.

In Comparative Example 4, Ni-20 wt% Cr-0.
6 wt% Y ₂ O ₃ composite powder and ceramic-free F
An e-base alloy was produced by sintering and solidifying using an HIP method without using an alloy foil.

Examples 9-1 obtained as described above
After the heat treatment was performed on the composite materials of Comparative Example 2 and Comparative Example 4, a tensile test piece was collected and subjected to a high-temperature tensile test (test temperature:
900 ° C.). FIG. 12 shows the results of the high temperature tensile test.

As is apparent from FIG. 12, the alloy foil constituting the composite material may be Ni-based, Cu-based, Al-based or A-based.
By using the u-based alloy foil, a suitable composite material can be provided.

[0099]

The composite material of the present invention is excellent in oxidation resistance, heat resistance and high-temperature strength.

Further, by using the method for producing a composite material of the present invention, a composite material having excellent oxidation resistance, heat resistance and high-temperature strength can be produced.

By using such a composite material of the present invention and a method for producing the same, for example, by manufacturing a shroud segment for a gas turbine or the like, it is possible to provide a gas turbine having excellent reliability and efficiency.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing an example of a method for producing a composite material of the present invention.

FIG. 2 is a conceptual diagram showing an example of another method for producing a composite material of the present invention.

FIG. 3 is a conceptual diagram showing an example of another method for producing a composite material of the present invention.

FIG. 4 is a conceptual diagram showing an example of a method for manufacturing a shroud segment for a gas turbine.

FIG. 5 is a conceptual diagram showing an example of a method for manufacturing a moving / static vane for a gas turbine.

FIG. 6 shows the results of an oxidation resistance evaluation test of Example 1 and Comparative Example 2.

FIG. 7 shows creep test results of Example 1 and Comparative Example 2.

FIG. 8 shows the results of a high temperature tensile test of Example 1 and Comparative Example 2.

FIG. 9 shows the results of high-temperature tensile tests of Examples 3, 4 and Comparative Example 2.

FIG. 10 shows the results of oxidation resistance evaluation tests of Examples 6, 7 and Comparative Example 3.

FIG. 11 shows results of creep tests of Examples 6, 7 and Comparative Example 3.

FIG. 12 shows the results of high-temperature tensile tests of Examples 9 to 12 and Comparative Example 4.

FIG. 13 is a conventional method for manufacturing a shroud segment for a gas turbine.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Conventional casting base material for gas turbine shroud segment 2 ... Conventional shroud segment for gas turbine 3 ... Alloy powder 4 ... Ceramic powder 5 ... Composite powder obtained by subjecting alloy powder and ceramic powder to alloying treatment 6 ... alloy foil 7 ... alloy not containing ceramic 8 ... metal tube 9 ... composite material 10 ... alloy powder not containing ceramic 11 ... metal container 12 ... outer ring portion 13 ... inner ring portion 14 ... shroud segment for gas turbine 15 ... moving / static Blade member 16: Moving / static blade for gas turbine

Claims (11)

[Claims] 1. A composite material wherein an alloy and a ceramic dispersion strengthened alloy are joined via an alloy foil. 2. The ceramic dispersion-strengthened alloy comprises Al
_2. The composite material according to claim 1, wherein the composite material contains at least one of ₂ O ₃ and Y ₂ O ₃ . 3. The composite material according to claim 1, wherein the ceramic dispersion strengthened alloy is mainly made of Fe or Ni. 4. The alloy foil is mainly composed of Ni, Cu, Al
The composite material according to any one of claims 1 to 3, wherein the composite material is made of any one of Au and Au. 5. A step of preparing a composite powder by compounding the composite alloy powder and the ceramic powder by a mechanical alloying process; and placing the alloy and the composite powder in a metal tube via an alloy foil; A process of integrating by a HIP method (hot isostatic pressing). 6. A step of preparing a composite powder by compounding the composite alloy powder and the ceramic powder by mechanical alloying treatment, and placing the alloy powder and the composite powder in a metal tube via an alloy foil. And a step of integrating by a HIP method (hot isostatic pressing). 7. A step of preparing a composite powder by compounding the composite alloy powder and the ceramic powder by a mechanical alloying treatment, and vacuuming the alloy powder and the composite powder in a metal container via an alloy foil. Encapsulating and integrating using a hot extrusion method. 8. The method according to claim 1, wherein the alloy powder and the composite powder vacuum-sealed through the alloy foil are inserted in layers in a direction parallel to, perpendicular to, or circumferentially opposite to the direction in which the metal container is extruded. 8. The method for producing a composite material according to item 7. 9. The ceramic powder is mainly composed of Al ₂ O.
₃ and Y ₂ O _3, etc. The method of producing a composite material according to any one of claims 5 to 8, characterized in that an oxide of. 10. The alloy foil is mainly composed of Ni, Cu, A
The method for producing a composite material according to any one of claims 5 to 9, wherein the method comprises any one of l and Au. 11. The composite material according to claim 1, wherein the composite material is used for manufacturing a shroud segment for a gas turbine or a moving and stationary blade for a gas turbine. The method for producing a composite material according to claim 1.