JPS62210329A - Ceramic coated heat-resistant material and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain heat shielding coating, high in reliability, by a method wherein the bonding layer of alloy, containing principal constituent of one of Ni and Co containing Cr and Al and excellent in resistances to high temperature oxidization and high temperature corrosion, is provided on a base material, which consists of a metallic material and the coating layer of ceramics, which contains the principal constituent of ZrO2, is formed on the bonding layer while an oxide layer, which contains the principal constituent of Al, is formed previously on a boundary between both layers. CONSTITUTION:Hastelloy-X (22wt%Cr-1.5wt%Co-9wt%Mo-19wt%Fe-0.1wt%C-balance Ni) or the alloy of Ni group is employed for a base material and the surfaces thereof are degreased and washed, thereafter, is blasted on a grid made of steel, then, the coating layer of metallic material, which consists of 10wt%Ni-25wt%Cr-7wt%Al-0.6wt%Y-5wt%Ta-balance Co, is formed by plasma spray coating so as to have the thickness of 0.01mm, thus, the bonding layer for a heat shielding coating is obtained. The coating layer of ZrO2-8wt%Y2O3 is formed immediately on the bonding layer so as to have the thickness of 0.3mm, then, the ceramics is applied so that the end of the bonding layer is exposed. The layers are heat- treated for 10hr in vacuum at the temperature of 1,060 deg.C to effect the diffusion treatment of the bonding layer and the base material.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat-resistant member used in high-temperature or high-temperature corrosive environments, and a method for manufacturing the same.

[Background Art] With the aim of improving the power generation efficiency of gas turbine plants for power generation, techniques for increasing the temperature of gas turbines are being studied. With such rising temperatures, it is desired to improve the heat resistance temperature of gas turbine members. Ni group or co
With the development of alloy materials such as base metals, the heat resistance temperature of these heat-resistant alloys has improved, but currently it is saturated at about 850°C. On the other hand, although ceramic materials are superior to metal materials in terms of heat resistance, they have problems such as toughness when used as structural materials. Therefore, in order to cope with such an increase in the temperature of the members, studies are actively being conducted on methods to prevent the members from reaching high temperatures.

Various methods for cooling one member have been studied as such methods. Another method is to coat the surface of a metal member with a ceramic having low thermal conductivity. Such coatings are called thermal barrier coatings (
It is called Thermal Barrier (1: oating, hereinafter abbreviated as TBC). When TBC is used in combination with various cooling methods, its effects become greater. - For example, there is a report that the temperature of the base metal member can be reduced by 50 to 100 degrees Celsius compared to one without TBC. By using such a method, the reliability of components such as high-temperature gas turbines can be improved. can improve sex. By the way, as a technical issue of TBC, T
Since BC is a combination of a heat-resistant alloy constituting the base material and a ceramic coating layer having different physical properties, there are problems with the adhesion mechanism between the base material and the ceramic coating layer and its reliability.

In particular, in gas turbines and the like, damage such as peeling and falling off of the ceramic coating layer occurs due to thermal cycles such as starting and stopping.

Therefore.

Various means have been used to solve these problems. The main methods include, for example, JP-A-55-1
As seen in Japanese Patent No. 12804, there is a method in which a bonding layer made of a metal material is provided between the ceramic coating layer and the base material. The purpose of the bonding layer is to alleviate the difference in physical properties between the base material and the ceramic coating layer. In this case, the adhesion mechanism between the ceramic coating layer and the bonding layer is merely a mechanical bond, and its strength is 2 to 5 kg/wm''.Furthermore, in addition to the bonding layer.

Some devices have a layer formed between the bonding layer and the ceramic coating layer, which is made of a mixture of an alloy material constituting the bonding layer and a material constituting the ceramic coating layer. This method is aimed at alleviating the difference in physical properties between the ceramic coating layer and the bonding layer, but in this case as well, the bonding state between the ceramic and the alloy material is only a mechanical bond. Therefore, if large thermal stress occurs in the TBC due to thermal cycles, etc.,
Damage such as peeling and falling will occur from areas where the bonding strength is weak.

Furthermore, the ceramic coating layer, bonding layer, and intermediate layer used in such TBCs are mainly formed by plasma spraying.

The reason for this is that in addition to the fast coating layer formation rate and excellent economic efficiency, it also utilizes the porous structure of the sprayed coating when applied to a ceramic coating layer. That is, by forming pores and fine racks, the pores and cracks are used to alleviate thermal stress. As described above, the ceramic sprayed coating formed by plasma spraying has a higher temperature than the dense ceramic coating layer formed by sputtering or other methods due to the heat tfJf'! ! Excellent in sex. However, since TBC is used at high temperatures and under high-temperature corrosion conditions due to impurities in the fuel, TBC has a porous ceramic coating layer formed by plasma spraying.
C has the problem of high-temperature oxidation and high-temperature corrosion of the alloy material forming the bonding layer or intermediate layer. Although alloy materials have excellent high-temperature oxidation and corrosion resistance, we believe that due to the method of forming the alloy coating layer, they do not necessarily exhibit the high-temperature oxidation and corrosion resistance expected of original alloy materials. According to studies conducted by the present inventors, when TBC was subjected to a thermal cycle test after being exposed to a high-temperature oxidation or high-temperature corrosive environment, it was found that its durability was significantly reduced. In this case, it is thought that in addition to the fact that the bond between the ceramic material and the alloy material is originally a mechanical bond and its strength is weak, the surface of the alloy material at the boundary was oxidized or corroded, further reducing the adhesion. It will be done.

[Problem that the invention seeks to solve]

In conventional TBCs, it is believed that the bonding strength between the ceramic and the alloy material is low, and that the surface of the alloy material changes due to high-temperature oxidation, high-temperature corrosion, etc., which further reduces the bonding strength of the ceramic alloy material. These problems greatly reduce the reliability of the TBC. In the plasma spraying method, in addition to the method of spraying in the atmosphere, there is also a method of spraying in a reduced pressure atmosphere in which the atmosphere around the plasma arc is controlled and the pressure of the atmosphere is also controlled. According to such thermal spraying in a reduced pressure atmosphere, the sprayed particles during thermal spraying are not contaminated by oxygen or the like, so that a very good metal alloy bonding layer can be formed. Such a metal alloy bonding layer is used as a coating layer to prevent high-temperature oxidation and high-temperature corrosion of high-temperature gas turbine components. In view of the above points, the present inventors conducted various studies focusing on strengthening the bonding mechanism between ceramic and alloy materials, with the aim of improving the reliability of TBC.

The present inventors have discovered that T
We considered BC. For example, a TBC consisting of a Zr0z ceramic coating layer and a bonding layer made of a metal alloy material
A high temperature oxidation test of TBC was carried out using the following. This test takes into account the construction of TBCs on gas turbine parts that are used under high-temperature conditions or that become locally hot. As a result, conventional TBC
It was found that oxidation at the interface between the system coating layer and the bonding layer progressed significantly. As a result of judging the adhesion of TBC before and after the test, Zr0z
It was found that the adhesion force at the interface between the system coating layer and the bonding layer was reduced by 172 to 1/4.

This decrease in adhesion is caused by the thickness of the Zr0z coating layer,
Although there are some differences in porosity and the type and amount of additives added to Zr0z, the decrease in both cases is remarkable.Also, there are some differences in the composition of the alloy material of the bonding layer, but both was also decreasing. Such a decrease in interfacial adhesion becomes more significant as the temperature of the oxidation test becomes higher or as the test time increases. And 1100℃, 1
In the 00 hour test, peeling damage from the interface was observed in some cases. On the other hand, in a TBC using a mixture of a metal alloy material and a ZrOx-based material as an intermediate layer, the decrease in adhesion in the oxidation test was even more remarkable. These results also correspond to the results of high-temperature thermal cycle tests conducted by the present inventors. That is, 970℃, 10
20℃.

Even in a test in which the test was held at each temperature of 1070°C and 1120°C for 30 minutes and repeatedly cooled to 150°C by air cooling, the number of repetitions until TBC damage occurred decreased significantly as the test temperature increased. Such problems with conventional TBCs become a serious obstacle in obtaining a highly reliable TBC that can cope with the high temperatures of gas turbines. In other words, TB is used for the purpose of preventing the base material temperature of gas turbine components from increasing and reducing the temperature.
When performing C, it is difficult to sufficiently reduce the base material temperature of parts with conventional TBC because the TBC has low high-temperature durability.

Therefore, the present inventors have developed a gas turbine component using a TBC with excellent high-temperature durability, which can sufficiently reduce the base material temperature of gas turbine components even under high-temperature operating conditions, in place of a gas turbine component with a conventional TBC. - Examined bottle parts.

That is, in consideration of the above points, the present inventors conducted various studies with the aim of obtaining a TBC sufficient to raise the temperature of the gas turbine, and the inventors have developed a TBC with excellent durability. This led to the invention of gas turbine parts.

An object of the present invention is to improve the reliability of TBC. That is, the object is to provide a TBC in which the bonding force between the ceramic material and the base material is stable over a long period of time, and is less prone to cracking or peeling.

[Means for solving problems]

The present invention forms, on a base material made of a metal material, a bonding layer of an alloy mainly composed of one of Ni or Co, containing Cr and Al, and having better high-temperature oxidation resistance and high-temperature corrosion resistance than the base material, In the heat-resistant member in which a ceramic coating layer containing ZrO2 as a main component is formed on the bonding layer, an oxide layer containing Al as a main component is formed in advance at the boundary between the bonding layer and the ceramic coating layer, and the bonding layer It is characterized by the exposed end.

The base material contains 35-61% by weight of Ni and 1-3% by weight of Co.
, a Ni-based alloy containing 14 to 27% by weight of Fe is desirable.

The bonding layer has Ni or co as the main component, and 10 to 3 Cr.
Alloys containing 0% by weight and 5-30% by weight Al are preferred. In addition to this, Hf, Ta, and Y.

It is more desirable to contain 0.1 to 5% by weight of one or more of Si and Zr.

The ceramic layer mainly contains ZrOx, CaO and Mg.
Preferably, it contains one of O and Y2O3.

Desirably, the amount of CaO is 4 to 10% by weight, the amount of MgO is 8 to 24% by weight, and the amount of YzOs is 4 to 20% by weight.
It is also possible to add two or more of sO, MgO, and Y2O3 in combination.

[Effect]

According to the present invention, the oxide layer containing Al as a main component is stable even in high-temperature atmospheres, prevents the progress of oxidation of the alloy bonding layer, and has strong bonding strength with the ceramic coating layer, so it can last for a long time. Even when used for a period of time, cracking and peeling of the ceramic coating layer can be prevented.

Furthermore, the presence of an exposed portion not covered by the ceramic coating layer on the end face of the bonding layer allows the Afl oxide layer to be formed more reliably. Such a TBC end face structure is very effective when applied to a perforated member such as a gas turbine combustor liner.

〔Example〕

The details of the present invention will be explained below. First, the conventional T
We examined the problems of BC in detail and investigated their causes. The s' of the cross-sectional structure of TBC subjected to various oxidation tests was examined. An example of the results is shown in FIGS. 5 and 6.

These microstructure photographs show the cross section of the bonding layer portion at a magnification of 100 times, and in FIG. 5, defects have occurred at the interface between the Zr0z-based ffW and the bonding layer. FIG. 6 shows the results of a TBC in which a mixed layer of an alloy material and a Zr0z-based material was formed between the bonding layer and the Zr0z-based coating layer. In this case, the alloy material of the intermediate layer is significantly oxidized. These phenomena are also observed in high temperature thermal cycle tests. That is, T
In BC, a problem arises in that the bonding layer or intermediate layer is oxidized through the Zr0z-based coating layer having a porous or micro-cracked structure to alleviate thermal stress. Such oxidation significantly reduces the adhesion of the interface.

Thermal stress or the like will cause peeling damage to the TBC from the interface. One of the important causes of such oxidation at the interface is thought to be that the Zr0z-based material becomes a semiconductor at high temperatures, facilitating the movement of oxygen and causing an increase in the oxygen partial pressure at the interface. . Such oxidation is considered to be more accelerated when an intermediate layer is formed, for example, because the area of the interface increases. As a result of analyzing the state of the interface of a conventional TBC, it was found that an oxide containing Cr as a main component was formed at the interface. Since such Cr-based oxides are unstable at high temperatures, damage occurs from the portion where the oxides are formed. Therefore, T for high temperature gas turbines
In BC, it is necessary to fully consider oxidation at the interface.

From this viewpoint, the present inventors investigated various methods and found that it is promising to form an oxide thin film with an m-dense structure containing Al as a main component at the interface. Al-based oxides are stable at high temperatures and Zr
Unlike 0z-based materials, it does not become a semiconductor at high temperatures. Therefore, a thin film of Afl-based oxide is effective as a barrier to prevent internal oxidation. On the other hand, when such an Al-based oxide layer is thick, it becomes a new intermediate layer that reflects the physical properties of the Afi-based oxide. As a result, due to thermal stress etc.
This will cause damage to the l-based oxide layer.

On the other hand, if it is too thin, it cannot serve as a barrier that satisfies the internal oxidation prevention effect. Therefore, its thickness is 0.1
It is desirable that the thickness is not less than μm and not more than 20 μm. The Al-based oxide layer in this range is sufficient as a barrier layer to prevent internal oxidation of the bonding layer. On the other hand, as an important effect in addition to the thin layer of Al-based oxide, Zr0z
It has been found that the adhesion between the ceramic and the bonding layer can be improved. That is, in contrast to the conventional TBC in which the ZrOx ceramic and the metal alloy constituting the bonding layer are mechanically bonded, the ZrOz ceramic is The adhesion between the bonding layer and the bonding layer is due to the interface between the oxides, Al-based oxide and Zr0z-based ceramic, and the Al-based oxide generated from the Al acid component in the metal alloy constituting the bonding layer. becomes very strong. - As an example, 1000° C. for a TBC with a thin film of such an Al-based oxide.

In a 500-hour oxidation test, the adhesion between the bonding layer and the Zr0z ceramic coating layer was 7 kg/m with almost no decrease.
m'' or more. Figure 1 shows an example of the cross-sectional structure of TBC after a high-temperature oxidation test, and the magnification is 100 times. No defects occurred, and the same was true in the oxidation test at 1100℃ for 100 hours, and no decrease in adhesion or generation of defects at the interface was observed.Furthermore, at 1030℃
.

Table 1 shows the results of a test in which the sample was held at each temperature of 1070°C, 1120°C, and 1170°C for 30 minutes, and was repeatedly cooled to 150°C by air cooling.

Table 1 Heat cycle test results Samples Nα201 to 204 in Table 1 are conventional TBC1Nα2
05 to 208 are the results of TBC having a thin film of Al-based oxide. As a result, TB with a thin film of hemium-based oxide
In case of C, the number of repetitions required for TBC to become damaged was about 3 to 7 times that of conventional TBC. Moreover, as the test temperature becomes higher, the effect becomes more pronounced. In this way, the present inventors have discovered that T with a thin film of AQ-based oxide
BC is particularly effective under high temperature conditions. Gas turbine components treated with such TBC remain stable even under high temperature conditions. Furthermore, T
In BC, the adhesion of the Zr0z coating layer is 7kg/me”
That's all. This adhesion force is much greater than the adhesion force of the ZrOx coating layer of conventional TBCs, which was about 3 to 5 kg/m''. Therefore, it prevents damage to the TBC due to combustion vibrations generated in combustor parts, etc. Therefore, the effects of applying TBC in this manner were investigated.

In gas turbine parts where the base material temperature is high, such as the combustor, the temperature of the base material can be reduced by applying TBC, which has excellent high-temperature durability, to the parts exposed to high-temperature combustion gas. It becomes possible to obtain stably. -As an example.

For cylindrical combustor liners, the inner surface of the cylinder exposed to high-temperature gas is coated with TBC, which has a thin film of Al-based oxide as described above, compared to parts coated with conventional TBC. The operating time before damage occurred was approximately three times as long. This is a TBC with a thin film of Al-based oxide.
This is because it has excellent durability, especially under high temperature conditions.

Therefore, the effect of reducing the combustor base material temperature obtained by applying TBC is stably maintained.

On the other hand, in combustor parts with conventional TBC, the TBC is damaged in a short period of time, and the damage to the TBC is particularly severe in areas where the base material temperature is high.As a result, the effect of reducing the temperature of the base material by TBC is disappears, and the temperature of the base material increases, leading to damage to the parts.

Further, in the combustor, the temperature of the base material is particularly likely to rise in parts where cooling with compressed air or the like cannot be performed sufficiently due to the strength of the base material or the structure such as fixation of the combustor. The role of TBC is particularly important in such areas.
In addition to reducing the temperature of the base material due to the heat shielding effect of BC, TBC, which has a ceramic coating layer with low thermal conductivity, also has the effect of preventing a local temperature rise of the base material and making the temperature of the base material uniform. have. As a result, TBC is extremely important in preventing local temperature increases in parts due to structural or combustion conditions, and in preventing deformation or damage to parts due to local temperature increases in the base material. Become something. The conventional TBC is
In particular, in parts where durability at high temperatures is a problem, and where the temperature of the base material locally increases, the TB of that part
C is easily damaged in a short period of time. In a combustor, the base material vibrates due to combustion vibrations, so TBCs with reduced adhesion of the ceramic coating layer are more likely to be damaged under high-temperature conditions.

Therefore, it becomes impossible to exert a sufficient effect on the part where the effect of TBC is most needed. and,
There is a possibility that the temperature of the base material may be higher in the damaged part of the TBC than in other parts where the TBC is healthy.
For example, in parts that are in contact with flame, such as a combustor, TBC
Also has the effect of reducing the amount of heat input from the flame to the base material due to the radiation effect of the ceramic coating layer. Therefore, the temperature of the base material in the damaged portion of the TBC may be higher than in the case where the TBC is not installed. As a result, it is difficult to fully demonstrate the effect of TBC in gas turbine parts such as combustor parts that have been applied with conventional TBC. T
Reliability may be impaired in parts that have been coated with BC. On the other hand, in the gas turbine parts of the present invention in which a TBC having a thin film of Al-based oxide is applied, even if the temperature of the base material is locally high, the TBC has excellent durability, especially at high temperatures. Therefore, the gas turbine parts of the present invention, in which a thin film of AΩ-based oxide is formed in advance, are difficult to damage the TBC in areas where the temperature of the base material increases. Even if the temperature rises locally, the heat shielding effect of the TBC is sufficiently maintained, and the effect of mitigating the local temperature rise caused by the TBC is also exerted. the result,
The gas turbine components of the present invention will be highly reliable.

In addition, for parts where the temperature of the base material becomes locally high,
It is also effective to apply a TBC containing Aa-based oxide to that part. In other words, due to the heat shielding effect of TBC,
This is because local temperature increases can be prevented.

Furthermore, if there is no TBC in other areas, the radiation effect of the TBC ceramic coating layer can reduce the amount of heat input to the base material in the area where the TBC is applied, reducing the amount of heat input from other areas without TBC. It can also be expected to maintain a balance between the two and prevent local temperature increases in the base material.

In this way, the TBC having a thin film of Al-based oxide can fully exhibit its effects in either case by being applied to the entire surface or a portion of the part of the gas turbine component that is exposed to high temperatures. Such a local temperature increase in the temperature of the base material.

As the temperature of the gas turbine increases, it tends to increase in size. 6 Therefore, gas turbine parts formed with a TBC having a thin film of Aa-based oxide are highly reliable.
This could enable gas turbines to reach higher temperatures. Hereinafter, the present invention will be explained in detail with reference to Examples.

Example 1 Hastelloy-X, a Ni-based alloy (22 wt% Cr-1,5 wt% CO-9 wt% Mo-19 wt% Fe-0,1 wt% C-balance Ni) was used as a base material. After degreasing and cleaning the surface, it was plasted using a steel grid, and then plasma sprayed to give a coating of 10% by weight.
Ni-25% by weight Cr77% by weight Al-0.6% by weight Y
A coating layer of an alloy material consisting of -5% by weight of Ta and the balance of Co was formed. Plasma spraying uses Ar at a pressure of 200 Torr.
I did it inside. In this case, the oxygen partial pressure in the atmosphere in which plasma spraying was performed was 10-δ atmospheres or less as measured by an oxygen sensor. The plasma output is 40kW. Under these conditions, Co, Ni, Cr, with a thickness of 0.01+w+
An AM, Y alloy coating layer was formed to serve as a bonding layer for the TBC.

Thereafter, a ZrOz 8% by weight Y x Oa coating layer was immediately formed on the above-described bonding layer. The thermal spraying conditions were a plasma output of 50 kW and thermal spraying in the atmosphere. Zr0z -8
The thickness of the %Y z Oa coating layer is 0.3 on. The ceramic was coated so that the edges of the bonding layer were exposed. Thereafter, a heat treatment was performed in vacuum at 1060° C. for 10 hours to perform a diffusion treatment between the bonding layer and the base material. For comparison, a TBC made of the same material as the TBC of the present invention and having a coating layer of the same thickness was prepared by a conventional method. As a conventional method, the aforementioned alloy material was thermally sprayed using Ar gas in the atmosphere, and then coated with ZrOx 8% Y2O3 in the same manner as described above. Next, in order to confirm the effects of the TBC of the present invention, various tests described below were conducted. First, oxidation tests were conducted at various temperatures.

Appearance observation and cross-sectional structure observation after the test, and an adhesion test were conducted. Table 2 shows the results of the appearance observation and adhesion test.

In Table 2, Na 1 to & 6 are the results of conventional TBC, )h7
-11 are the results of the TBC of the present invention created in this example. That is, in the conventional TBC, at a temperature of 1070°C or higher (held for 100 hours), Zr0z-8%Y z Oa
The coating layer peeled off and the TBC was damaged. On the other hand, &7 of the present invention
- &11 TBC has no external damage.

On the other hand, the results of the TBC adhesion test after the oxidation test also showed that TBC
The conventional TBC of Nα1-Na6 with undamaged C is
The adhesion was 2 to 5 kg/-2, and the adhesion decreased as the oxidation test temperature increased. Furthermore, the fractured portion in the adhesion test was the boundary between the bonding layer and the Zr0z -8% Y2O3 coating layer. On the other hand, in the TBC of the present invention shown in 翫7～N[Lll, no decrease in the adhesion of the TBC was observed under any oxidation test conditions,
7kg, which is the limit value of the adhesion test method using
/mu'' or more. Therefore, all the broken parts after the test were adhesive parts.

Next, a thermal cycle test was conducted using the test piece after the above oxidation test. Test conditions were 750°C, 15 minutes hold, 20
- Repeated holding in water at ~25°C for 15 seconds. Table 3 shows the results.

Table 3 Thermal Cycle Test Results The samples in Table 3 are samples after each oxidation test was conducted. The conventional TBC of Nα1~&3 in Table 3 is 200~
After 500 thermal cycle tests, the Zr0z-8% Y2O3 coating layer peeled off and the TBC was damaged.

On the other hand, the TBC of the present invention with Na 7 to Na 11 in Table 3 is
There was no damage even after repeated thermal cycles of 1400 to 17oO times, and damage to the TBC was observed after a maximum of 1700 thermal cycles. In this way, the TBC of the present invention is similar to the conventional TBC.
It is a highly durable TBC with superior high-temperature oxidation resistance and thermal shock resistance compared to BC.

Example 2 A TBC was prepared using the same materials as in Example 1 and under the same thermal spraying conditions as in Example 1, and then heated in vacuum at 1060° C. for 3 hours to form Co.

A bonding layer consisting of Ni, Cr, Al, and Y coating layers and a base material were subjected to a diffusion treatment. Furthermore, after that.

Heat treatment was performed in the air at 1000° C. for 15 hours. The TBC of the present invention produced in this way contains Zr0z-8%
Y2O3 coating layer and Co, Ni, Cr.

, +ll, a boundary layer approximately 5 μm thick was formed almost uniformly at the interface with the Y coating layer. The boundary layer is EPNA
As a result of analysis or X-ray diffraction, it was found that the main component was Afl-based oxide. For comparison, the same material as the TBC of the present invention was used.

A TBC was prepared by the conventional method, and the TBC was subjected to the same vacuum diffusion treatment and atmospheric heat treatment as the TBC of the present invention. 1 In Table 3, &101 and &102 indicate the TBC of the present invention and the TBC of the present invention prepared in this way. Conventional TBC for comparison
These are the results of a heat cycle test similar to that in Example 1 using the following. The conventional TBC of N11101 in Table 3 is approximately 5
After 00 repetitions, the Zr0z-8% YtOa coating layer was peeled off. On the other hand, the TBC of the present invention with Nα102 in Table 3 was damaged after about 1500 repetitions. Thus, the TBC of the present invention has approximately three times the durability compared to conventional TBCs.

Next, FIG. 2 shows an example in which the present invention is applied to a gas turbine combustor liner.

The construction part of the TBC is the inner surface of the cylindrical part of the combustor liner 1 shown in FIG. This combustor liner 1 has cooling air openings (hereinafter referred to as louvers 2), but since the metal temperature becomes very high, a TBC was installed in the part shown by A in FIG. 2. The material of the base material of the combustor liner 1 is Hastelloy-X (22%Cr-1, 5%C0-9%Mo-1
A TBC having an Lp, n-based oxide (9% Fe-0, 1% C-remaining Ni) was formed using plasma spraying. The details are as follows. First, the liner was degreased and cleaned, and then grid plasted with AnaOa. Immediately apply 10% Ni- to the surface of such a base material.
25%Cr-7%Al2-0.6%Y-5%Ta-
An alloy material with the balance being Co was plasma sprayed to form a bonding layer. As conditions for forming such a bonding layer, it is desirable that the plasma output be high and that the atmosphere around the plasma jet during melting be controlled. In particular, as an element of atmosphere control, it is preferable to reduce the oxygen partial pressure, preferably to 10-8 atmospheres or less.
Further, as another element of atmosphere control, it is desirable to carry out the process in a reduced pressure atmosphere. By controlling the atmosphere in this manner, it is possible to form a bonding layer that is preferable for obtaining the present invention.On the actual flow side of the 6 tubes, the oxygen partial pressure is set to 10-3 atmospheres or less in an Ar atmosphere, and , the atmospheric pressure is 200
The test was carried out in an atmosphere controlled to Torr. Further, in order to obtain the present invention, it is preferable to maintain the substrate temperature during thermal spraying at 500 to 1000°C. In this example, 600 to 700
It was carried out within the range of °C. Under these conditions, the thickness of approximately 0
．． A bonding layer of 1 ms+thickness was formed. Thereafter, a coating layer of a ceramic material consisting of Zr0z -6% Y2O3 was formed on this bonding layer. The coating layer was formed by plasma spraying. Thermal spraying conditions used high-power plasma spraying, and
It was carried out with an output of kW. The thickness of the covering layer is approximately 0.3 m.

After forming the TBC in this way, one part was heated in a vacuum to perform a diffusion treatment between the bonding layer and the base material. The diffusion process was carried out at 1060°C in a vacuum of about 10-II Torr at 5°C.
This is a condition for holding time. After that, it was heated to 900℃ in the atmosphere.
, heat treatment was performed for 20 hours. There are no particular restrictions on the conditions for the diffusion treatment or heat treatment, but the diffusion treatment should be at or below the thermal spraying temperature of the base material.

It is preferable to conduct the heat treatment at a temperature of 800°C or higher for 3 hours or more and 100 hours or less, while heat treatment is performed at a temperature of 60°C or higher and 100°C or higher.
It is preferable to conduct the heating at a temperature of 200° C. or lower for 1 hour or more and 200 hours or less. In this way, a combustor liner of the present invention coated with TBC having an Al-based thin film was produced. The combustor liner 1 has a structure including cooling louvers 2 as shown in FIG. In order for the louver 2 to exhibit its cooling effect sufficiently, its dimensions must fall within a predetermined range. If the thickness of the TBC becomes extremely thick in a part of the louver, the cooling effect of that part will be significantly reduced, leading to an increase in the temperature of the base material.

When the thickness of TBC locally increases, the T of that area increases.
The durability of BC is significantly reduced.

As shown in FIG. 3, in the thermal spraying of the bonding layer 5, first, the louver corners 2 on the flame side of the inner surface 3, which may be exposed to flame, without reducing the air inflow area of the cooling air holes 2a.
When spraying the zero-order ceramic layer 6 while facing the upstream side 1b or downstream side 1a of the combustor, the spraying direction B is applied to the end of the bonding layer 5 so as to spray up to the louver corner 2c on the air side. The spraying direction is such that the ends 6a, 6b of the ceramic layer 6 are offset from the parts 5a, 5b, and the ends 6a, 6b of the ceramic layer 6 are on the bonding layer 5.
It is constructed so as to face the combustor downstream side 1a with respect to the axis. As a result, a boundary layer made of Aα-based oxide is always present at the boundary between the bonding layer 5 and the ceramic coating layer 6, and a TBC with excellent durability can be obtained. The above-mentioned thermal spraying method is applicable not only around the cooling air holes but also around the T.
It can also be applied to the boundary between the part where BC is applied and the part where it is not, or around the combustion air hole of the combustor.

Under these conditions, the bonding layer or ZrO2-6%Y2
．． By forming the 06 coating layer, T
A TBC without a thick BC was obtained. The TBC of the combustor liner formed in this way has a cross-sectional structure almost similar to that shown in Fig. 1, and has a bonding layer and Zr0z 6%Y x
A boundary layer made of Al-based oxide and having a thickness of about 3 μm was formed at the interface with the Oa coating layer. Using this combustor liner, a thermal cycle test was conducted in which the liner was held at 1000°C for 30 minutes and held in water at 20 to 25°C for 5 minutes. or,
For comparison, a similar thermal cycle test was conducted using a TBC that did not have an Al-based oxide thin film formed in the same manner as the combustor liner of the present invention. As a result, 1 the combustor liner of the present invention did not cause any damage to the TBC even after 50 repetitions, whereas the combustor liner with the conventional TBC suffered damage to the TBC after approximately 90 repetitions.

A combustion test was conducted under the same conditions using the combustor liner of the present invention produced as described above and a conventional combustor liner produced for comparison. As a result, about 15
In the 00 hour test, the conventional TBC showed a range of A in FIG. Damage to the TBC occurred in areas without cooling louvers. On the other hand, in the combustor liner of the present invention, no damage to the TBC was observed in all parts.
After the test, the combustor liner was cut in the area A in FIG. 2, and the state of the TBC was observed. As a result, [%] of the cross-sectional tissue showed that no damage had occurred in any part of the TBC.

Further, in the combustor liner of the present invention, the dimensional change in the liner diameter in the area A in FIG. 2 was about 3% or less. On the other hand, in a conventional combustor with a damaged TBC, the dimensional change was as large as about 5% of the liner diameter.1 The combustor liner of the present invention maintains the effect of the TBC over a long period of time. This is sufficiently effective in preventing problems such as deformation of the combustor liner.

The present invention was applied to a combustor liner 4 having the structure shown in FIG. In the combustor liner having this structure, the temperature of the base material increases significantly in the range shown by C in FIG.

Therefore, the combustor liner of the present invention was fabricated by applying TBC to the inner surface of portion C in FIG. 4, which is exposed to combustion gas, using the same coating layer material as in FIG. 2 and under the same conditions. did. For comparison, a combustor liner was prepared in which a conventional TBC without an Aa-based oxide thin film was applied to the portion C in FIG. 4. Tests were conducted under identical combustion conditions using each combustor liner. As a result, in the combustion tank liner of the present invention, no damage to the TBC was observed even after about 2000 hours of testing, and no deformation of the combustor liner such as a change in liner diameter occurred. On the other hand, in a combustor liner with a conventional TBC, the TBC was significantly damaged after about 2000 hours of testing. Also, the change in liner diameter in that area is large,
Deformation of the combustor liner had occurred. As described above, the combustor liner of the present invention, in which TBC is applied only to the portions of the base material where the temperature becomes high, has sufficient durability and reliability. Furthermore, for the combustor liner shown in Fig. 4,
Similar to the example shown in FIG. 2, the same effects as in this embodiment can be obtained even when TBC is applied to the entire inner surface of the liner.

FIG. 7 shows another embodiment, and similarly to FIG. 3, it shows the cooling air inflow hole 2a of the combustor. FIG. 7 shows a case in which, unlike the louver type described above, a ring 7 is attached to the inner surface 3 so that cooling air flows along the inner surface. In this figure as well, the bonding layer 5 and the ceramic layer 6 are formed as described above, and the bonding layer ends 5a, 5b and the ceramic layer ends 6a, 6b are the ceramic layer end 6.
a, 6b are located on the bonding layer 5, and.

It is constructed apart from the ends 5a and 5b of the bonding layer. Therefore, in the case of bonded layer spraying, the spraying direction B is relative to the axis,
The upstream side 1b color is applied facing the downstream side 1a, but when ceramic layer is thermally sprayed, - is applied so as to face the downstream side 1a with respect to the axis. Even in this structure, the durability of the TBC can be improved in a economical manner according to the present invention.

The present invention is useful for other gas turbine combustors that are exposed to high temperature conditions. Furthermore, the bonding layer material constituting the TBC has an alloy containing 5% or more of Al, and the material constituting the ceramic coating layer has ZrO2 as a main component, and Cab and MgO are used as stabilizers.

Those containing any one of Y x O a and the like are preferred.

Regarding the thickness of each coating layer. Considering the heat shielding effect and durability of TBC, the bonding layer is 0.03
m or more and 0.5 mm or less, Zr0z-based coating layer is 0.05
The length is preferably 0.8 m or more.

〔Effect of the invention〕

As explained above, according to the present invention, progress of oxidative corrosion of the bonding layer can be prevented, so that the bonding strength of the ceramic coating layer can be stably maintained over a long period of time.

[Brief explanation of drawings]

Figure 1 is a micrograph showing the metal structure of a cross section of a TBC according to the present invention, Figure 2 is an external view of a gas turbine combustor liner to which TBC is applied, and Figure 3 is the vicinity of the louver of the liner in Figure 2. Figure 4 is an external view of another type of combustor liner treated with rBc, Figures 5 and 6 are micrographs showing the metallographic structure of a cross section of conventional TBC after high temperature oxidation. The photograph, FIG. 7, is a cross-sectional view of another type of combustor liner. DESCRIPTION OF SYMBOLS 1... Combustor liner, 2... Louver, 5... Bonding layer, 6... Ceramic layer.

Claims (1)

[Scope of Claims] 1. On a base material containing at least one of Ni, Co, and Fe as a main component, containing one of Ni or Co as a main component and containing Cr and Al, which has higher temperature oxidation resistance than the base material. , in a heat-resistant member having a bonding layer made of an alloy with excellent high-temperature corrosion resistance, and having a coating layer made of ceramic containing ZrO_2 as a main component on the bonding layer, the bonding layer is formed on the end face of the bonding layer and the ceramic coating layer. A ceramic-coated heat-resistant member, characterized in that the layer has an exposed portion, and an oxide layer containing Al as a main component is previously provided at the boundary between the bonding layer and the ceramic coating layer. 2. In claim 1, the material constituting the ceramic coating layer contains ZrO_2 as a main component and Ca
A ceramic-coated heat-resistant member characterized by containing one or more of O, MgO, and Y_2O_3. 3. In claim 1, the material constituting the bonding layer of the alloy contains either Co or Ni as a main component, 10 to 30% by weight of Cr, and 5 to 3% by weight of Al.
1. A ceramic-coated heat-resistant member comprising an alloy containing 0% by weight and further containing 0.1 to 5% by weight of one or more of Hf, Ta, Y, Si, and Zr. 4. A ceramic-coated heat-resistant member according to claim 1, wherein the oxide layer has a thickness of 0.1 μm to 20 μm. 5. Claim 1, characterized in that the alloy bonding layer has a thickness of 0.03 mm to 0.5 mm, and the ceramic coating layer has a thickness of 0.05 mm to 0.8 mm. Ceramic coated heat resistant parts. 6. The surface of a base material composed of at least one of Ni, Co, and Fe as a main component contains one of Ni or Co as a main component and contains Cr and Al, and has higher temperature oxidation resistance and higher temperature than the base material. a step of forming a bonding layer of an alloy with excellent corrosion resistance; and a step of forming a coating layer made of ceramic containing ZrO_2 as a main component on the surface of the bonding layer, and exposing and covering the edges of the bonding layer at this time. A method for manufacturing a ceramic-coated heat-resistant member, comprising: a heat treatment step of forming an oxide layer containing Al as a main component at the boundary between the bonding layer and the ceramic coating layer. 7. A method for manufacturing a ceramic-coated heat-resistant member according to claim 6, characterized in that the bonding layer is formed by plasma spraying in an atmosphere with an oxygen partial pressure of 10-3 atmospheres or less. 8. In claim 6, the step of forming the oxide layer includes a step of heat treatment in the air at a temperature range of 600° C. to 1200° C. for 1 hour to 200 hours. A method for manufacturing a ceramic-coated heat-resistant member.