JP6821496B2 - Thermal barrier coating forming method, thermal barrier coating, and high temperature member - Google Patents

Description

The present invention relates to a method for forming a heat shield coating, a heat shield coating, and a high temperature member.

In the gas turbine, the temperature of the gas used is set high in order to improve its efficiency. Turbine members such as rotor blades and stationary blades that are exposed to such high-temperature gas have a thermal barrier coating (TBC) applied to their surfaces. The heat shield coating is a coating on the surface of a turbine member, which is an object to be sprayed, with a thermal spray material having a low thermal conductivity (for example, a ceramic material having a low thermal conductivity) by thermal spraying. By forming the heat shield coating on the surface, the temperature of the high temperature member exposed to the environment of high temperature and high pressure is lowered, and the durability is improved.

Patent Document 1 describes a method of using suspension plasma spraying as a method of forming a heat shield coating on a metal part of a gas turbine engine. Suspension plasma spraying uses a suspension in which microparticles are dispersed in water or alcohol-based carriers. In suspension plasma spraying, microparticles melted by evaporation or combustion by a plasma jet are deposited on the contact surface. As a result, a homogeneous ceramic layer is formed on the surface of the base material by the molten microparticles.

JP 2015-166479

By the way, as a dense ceramic layer in the heat shield coating, a DVC (Dense Ceramicy Crack) coating having vertical division may be formed. The DVC coating has an improved erosion resistance because it has a dense structure having a vertically divided structure. However, it is known that the DVC coating has a dense structure, so that the porosity is reduced and the heat shielding property is lowered. That is, in the case of a heat-shielding coating, if the porosity is lowered in order to improve the erosion resistance, the thermal conductivity is increased and the heat-shielding performance is lowered.

The present invention has been made in view of the above circumstances, and provides a heat-shielding coating forming method, a heat-shielding coating, and a high-temperature member capable of enhancing the heat-shielding effect while suppressing a decrease in erosion resistance. The purpose.

The present invention employs the following means in order to solve the above problems.
The thermal barrier coating according to the first aspect of the present invention is formed on a heat-resistant alloy base material and includes a ceramic layer containing ceramic, and the ceramic layer is laminated on the first dense layer and the first dense layer. , an intermediate pore layer, wherein said first plurality of pores density greater than the dense layer is formed, the laminated an intermediate pore layer, have a, a second dense layer density is less than the intermediate pore layer In the first dense layer, the first vertical division extending in the thickness direction is dispersed in the surface direction, and in the second dense layer, the second vertical division extending in the thickness direction is dispersed in the surface direction. The vertical split and the second vertical split extend at an angle with respect to the surface of the ceramic layer .

According to such a configuration, the intermediate pore layer is formed between the first dense layer and the second dense layer, so that heat input to the ceramic layer in the thickness direction is hindered by the intermediate pore layer. .. As a result, the thermal conductivity of the ceramic layer can be reduced. Further, in the ceramic layer, the first dense layer is formed on the heat-resistant alloy base material side, so that the adhesion to the heat-resistant alloy base material can be ensured. Further, in the ceramic layer, the erosion resistance can be ensured by forming the second dense layer on the surface side.
Further, the heat input in the thickness direction of the ceramic layer is hindered by the diagonally extending first vertical division and the second vertical division. Therefore, the thermal conductivity in the ceramic layer can be reduced by the first vertical division and the second vertical division. On the other hand, by forming the ceramic layer so densely that the first vertical division and the second vertical division are formed, it is possible to suppress a decrease in erosion resistance.

Further, in the heat shield coating according to the second aspect of the present invention, in the first aspect, the first boundary portion which is the boundary portion between the intermediate pore layer and the first dense layer and the intermediate pore layer and the second dense layer. At the second boundary, which is the boundary with the layer, the porosity may change continuously.

Further, in the heat shield coating according to the third aspect of the present invention, the porosity of the intermediate pore layer may be 10% or more and 20% or less in the first aspect or the second aspect.

With such a configuration, the effect of inhibiting heat input to the ceramic layer in the thickness direction is increased over a wide area in the surface direction. As a result, the thermal conductivity of the topcoat layer can be significantly reduced without significantly reducing the erosion resistance of the intermediate pore layer.

Further, in the heat shield coating according to the fourth aspect of the present invention, in any one of the first to third aspects, the porosity of the first dense layer and the second dense layer is 10% or less and 5%. It may be the above.

Further, in the heat shield coating according to the fifth aspect of the present invention, in any one of the first to third aspects, the inclination angle of the first vertical division with respect to the surface of the ceramic layer and the second vertical division The angle of inclination of the ceramic layer with respect to the surface of the ceramic layer may be different.

Further, the high temperature member according to the sixth aspect of the present invention includes a heat-resistant alloy base material and a heat- shielding coating formed on the heat-resistant alloy base material in any one of the first to fifth aspects .

According to the present invention, the heat shielding effect can be enhanced while suppressing the decrease in erosion resistance.

It is a schematic block diagram of the gas turbine which concerns on embodiment of this invention. It is a schematic structural perspective view of the moving blade which concerns on embodiment of this invention. It is sectional drawing of the main part of the moving blade explaining the heat shield coating which concerns on embodiment of this invention. It is a process drawing explaining the process of the heat shield coating forming method in 1st Embodiment of this invention. It is a figure which obtained the relationship between the thermal conductivity and the porosity in the top coat layer in the embodiment of this invention by simulation. FIG. 5 is a diagram obtained by simulation of the relationship between the thermal conductivity and the inclination angle of the vertical division in the top coat layer in which the vertical division is formed in the embodiment of the present invention. It is sectional drawing of the main part of the moving blade explaining the heat shield coating which concerns on the modification of this invention.

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 7.
As shown in FIG. 1, the gas turbine 1 of the present embodiment includes a compressor 2, a combustor 3, a turbine main body 4, and a rotor 5. The compressor 2 takes in a large amount of air inside and compresses it. The combustor 3 mixes fuel with compressed air A compressed by the compressor 2 and burns it.

The turbine body 4 converts the thermal energy of the combustion gas G introduced from the combustor 3 into rotational energy. The turbine main body 4 converts the thermal energy of the combustion gas G into mechanical rotational energy by blowing the combustion gas G onto the moving blades 7 provided in the rotor 5, and generates power. In addition to the plurality of moving blades 7 on the rotor 5 side, the turbine main body 4 is provided with a plurality of stationary blades 8 in the casing 6 of the turbine main body 4. In the turbine body 4, the moving blades 7 and the stationary blades 8 are alternately arranged in the axial direction of the rotor 5. The rotor 5 transmits a part of the rotating power of the turbine body 4 to the compressor 2 to rotate the compressor 2.

Hereinafter, in this embodiment, the moving blades 7 of the turbine body 4 will be described as an example of the high temperature member of the present invention.
As shown in FIG. 2, the moving blade 7 has a moving blade main body 70 and a heat shield coating 100. The rotor blade body 70 is a heat-resistant alloy base material formed of, for example, a well-known heat-resistant alloy material such as a Ni-based alloy. The moving blade main body 70 of the present embodiment includes a wing main body portion 71, a platform portion 72, a wing root portion 73, and a shroud portion 74.

The wing body 71 has a wing-shaped cross section. The blade body 71 is arranged in the flow path of the combustion gas G in the casing 6 of the turbine body 4. The platform portion 72 is provided at the base end of the wing body portion 71. The platform portion 72 defines a flow path of the combustion gas G on the proximal end side of the blade main body portion 71. The wing root portion 73 is formed so as to project from the platform portion 72 to the side opposite to the wing body portion 71. The shroud portion 74 is provided at the tip of the wing body portion 71. The shroud portion 74 defines a flow path of the combustion gas G on the tip end side of the blade main body portion 71.

As shown in FIG. 3, the heat shield coating 100 is formed on the surface of the rotor blade body 70, which is a heat-resistant alloy base material. The heat shield coating 100 includes the surface of the blade body 71, the surface of the platform portion 72 connected to the blade body 71, and the surface of the shroud portion 74 of the surface of the blade body 70. It is formed so as to cover the surface on the connected side. The heat shield coating 100 of the present embodiment is formed by suspension plasma spraying described later. The heat shield coating 100 of the present embodiment includes a bond coat layer 110 and a top coat layer (ceramic layer) 120.

The bond coat layer 110 is formed directly on the surface of the rotor blade body 70. The bond coat layer 110 suppresses the top coat layer 120 from peeling off from the rotor blade body 70. The bond coat layer 110 is a metal bonding layer having excellent corrosion resistance and oxidation resistance. The bond coat layer 110 is formed, for example, by spraying a metal spray powder of MCrAlY alloy as a spray material onto the surface of the rotor blade body 70. Here, "M" of the MCrAlY alloy constituting the bond coat layer 110 indicates a metal element. The metal element "M" is composed of, for example, a single metal element such as Ni or Co, or a combination of two or more of these.

The top coat layer 120 is formed on the rotor blade body 70 via the bond coat layer 110. The top coat layer 120 has a layer containing ceramic in which vertically divided C extending in the thickness direction is dispersed in the surface direction. Here, the surface direction is a direction along the surface of the top coat layer 120. The top coat layer 120 of the present embodiment is formed with a thickness of 0.3 mm or more and 1.5 mm or less. The top coat layer 120 has a first dense layer 121, an intermediate pore layer 122, and a second dense layer 123.

The first dense layer 121 is directly laminated on the bond coat layer 110. In the first dense layer 121, as the vertical division C, the first vertical division C1 is dispersed in the plane direction in which the surface spreads. Therefore, in the first dense layer 121, a plurality of first vertically split C1s are formed apart from each other in the plane direction. The first dense layer 121 of the present embodiment is, for example, a dense DVC (Dense Virtual Crack) coating in which the first vertical split C1 is dispersed in the plane direction. The first dense layer 121 is formed on the heat-resistant alloy base material side of the top coat layer 120. The thermal spray material used to form the first dense layer 121 is, for example, yttria-stabilized zirconia (YSZ) or yttria-stabilized zirconia (ZrO ₂ ) partially stabilized with ytterbium oxide (Yb ₂ O ₃ ). Zirconia chemicals (YbSZ) are used.

The first vertical split C1 is inclined and extends by a predetermined inclination angle α with respect to the surface of the top coat layer 120. Specifically, the first longitudinal division C1 extends the extending direction of the virtual straight line connecting the base end on the surface side of the heat-resistant alloy base material in the thickness direction and the tip end on the surface side of the top coat layer 120. The direction is. In the first vertical division C1, the extending direction is inclined with respect to the surface direction in which the surface of the top coat layer 120 spreads. Therefore, the first vertical split C1 extends from the base end toward the surface of the top coat layer 120 toward one side in the surface direction with respect to the base end. The inclination angle α in the present embodiment is an angle in the extending direction with respect to the surface direction. In the present embodiment, the plurality of first vertical divisions C1 are all inclined toward the same direction. That is, all of the plurality of first vertical divisions C1 are inclined toward one side in the surface direction toward the surface of the top coat layer 120. Further, the first vertical split C1 is inclined not only in a part of the proximal end side and the distal end side but also in the entire area in the thickness direction.

The inclination angle α in the present embodiment is preferably an angle of 45 ° or more and 80 ° or less with respect to the surface of the top coat layer 120. The inclination angle α is more preferably an angle of 50 ° or more and 70 ° or less with respect to the surface of the top coat layer 120. The inclination angle α is particularly preferably an angle of 55 ° or more and 65 ° or less with respect to the surface of the top coat layer 120.

In the first dense layer 121, the distribution ratio of the first vertical division C1 per 1 mm is preferably 6 / mm or more and 12 / mm or less. In the first dense layer 121, it is more preferable that the distribution ratio of the first vertical division C1 per 1 mm is 8 lines / mm or more and 10 lines / mm or less.

The porosity of the first dense layer 121 is preferably within the range of 10% or less and 5% or more. The porosity in the present embodiment is not only the occupancy rate of only the pores P per unit volume, but also the occupancy rate of the vertically divided C and the pores P combined.

The intermediate pore layer 122 is laminated on the first dense layer 121. The intermediate pore layer 122 has a higher density than the first dense layer 121, and a large number of pores P are formed. Therefore, the intermediate pore layer 122 is a porous film formed with a porosity larger than that of the first dense layer 121, and has almost no vertical division C inside. The intermediate pore layer 122 of the present embodiment is formed to have the same thickness as the first dense layer 121. The intermediate pore layer 122 of the present embodiment is formed of the same sprayed material as the first dense layer 121.

The porosity of the intermediate pore layer 122 of the present embodiment is preferably 10% or more and 20% or less. The porosity of the intermediate pore layer 122 is more preferably 12% or more and 18% or less. The porosity of the intermediate pore layer 122 is particularly preferably 14% or more and 16% or less.

At the first boundary portion, which is the boundary portion between the intermediate pore layer 122 and the first dense layer 121, the porosity changes continuously. Therefore, the porosity is formed so as to gradually increase from the vicinity of the center in the thickness direction of the first dense layer 121 toward the vicinity of the center in the thickness direction of the intermediate pore layer 122.

The second dense layer 123 is directly laminated on the intermediate pore layer 122. In the second dense layer 123, the second vertical division C2 is dispersed in the plane direction as the vertical division C. Therefore, in the second dense layer 123, a plurality of second vertically divided C2s are formed apart from each other in the plane direction. The second dense layer 123 has a higher density than the intermediate pore layer 122. The second dense layer 123 is formed on the most surface side of the top coat layer 120. Therefore, the surface of the second dense layer 123 is the surface of the top coat layer 120. The second dense layer 123 of the present embodiment is, for example, a dense DVC coating in which the second vertical split C2 is dispersed in the plane direction. The second dense layer 123 of the present embodiment is a film having the same structure as the first dense layer 121. Therefore, the thermal spraying material used when forming the second dense layer 123 is the same thermal spraying material as the first dense layer 121.

Similar to the first vertical division C1, the second vertical division C2 extends at an inclination angle α with respect to the surface of the top coat layer 120. Specifically, the second vertical split C2 extends in the extending direction of the virtual straight line connecting the base end on the surface side of the heat-resistant alloy base material in the thickness direction and the tip end on the surface side of the top coat layer 120. The direction. In the second vertical division C2, the extending direction is inclined with respect to the surface direction in which the surface of the top coat layer 120 spreads. Therefore, similarly to the first vertical division C1, the second vertical division C2 extends from the base end toward the surface of the top coat layer 120 toward one side in the surface direction with respect to the base end. The second vertical division C2 of the present embodiment is inclined at the same angle in the same direction as the first vertical division C1. The plurality of second vertical divisions C2 are all inclined toward the same direction. That is, all of the plurality of second vertical divisions C2 are inclined toward one side in the surface direction toward the surface of the top coat layer 120. Further, the second vertical split C2 is inclined not only in a part of the proximal end side and the distal end side but also in the entire area in the thickness direction.

In the second dense layer 123, the distribution ratio of the second vertical division C2 per 1 mm is preferably 6 lines / mm or more and 12 lines / mm or less. In the second dense layer 123, it is more preferable that the distribution ratio of the second vertical division C2 per 1 mm is 8 lines / mm or more and 10 lines / mm or less. The porosity of the second dense layer 123 is preferably within the range of 10% or less and 5% or more. In the second dense layer 123, it is preferable that the distribution rate of the second vertical division C2 per 1 mm is the same as the distribution rate of the first vertical division C1 of the first dense layer 121. The porosity of the second dense layer 123 is preferably the same as the porosity of the first dense layer 121.

At the second boundary, which is the boundary between the intermediate pore layer 122 and the second dense layer 123, the porosity changes continuously. Therefore, the porosity is formed so as to gradually decrease from the vicinity of the center in the thickness direction of the intermediate pore layer 122 toward the vicinity of the center in the thickness direction of the second dense layer 123.

Next, a method S1 for manufacturing a high temperature member will be described. The method S1 for manufacturing a high temperature member of the present embodiment is a method for manufacturing a moving blade 7 that manufactures the above-mentioned moving blade 7 as a high temperature member. As shown in FIG. 4, the method S1 for manufacturing a high-temperature member of the present embodiment includes a blade main body preparation step S10 and a heat shield coating forming step S20.

In the moving blade body preparation step S10, a heat-resistant alloy base material is prepared in advance as the moving blade body 70. In the rotor blade body preparation step S10 of the present embodiment, the material is formed and prepared so as to have the shape of the target high temperature member (for example, the rotor blade body 70 in the present embodiment).

In the heat shield coating forming step S20, the heat shield coating 100 is formed on the surface of the rotor blade body 70 prepared in the rotor blade body preparation step S10 by the heat shield coating forming method S100. In the heat shield coating forming step S20 of the present embodiment, the bond coat layer 110 and the top coat layer 120 are formed on the surface of the rotor blade main body 70. The thermal barrier coating forming step S20 of the present embodiment is carried out by the following thermal barrier coating forming method S100.

The heat shield coating forming method S100 forms the heat shield coating 100 on the rotor blade main body 70. The heat shield coating forming method S100 of the present embodiment includes a bond coat layer forming step S110, a top coat layer forming step (ceramic layer forming step) S120, and an adjusting step S130.

The bond coat layer forming step S110 forms the bond coat layer 110 on the surface of the rotor blade body 70. The bond coat layer forming step S110 is carried out after the rotor blade main body preparation step S10. In the bond coat layer forming step S110, for example, the sprayed particles of the MCrAlY alloy are sprayed onto the surface of the rotor blade body 70 with a spray gun. In the bond coat layer forming step S110, the thermal spray gun is moved so that the injection holes of the thermal spray particles are perpendicular to the surface of the rotor blade body 70. In the bond coat layer forming step S110 of the present embodiment, the bond coat layer 110 is formed by performing high-speed frame spraying (HVOF: High Velocity Oxygen Fuel) or reduced pressure plasma spraying (LPPS: Low Pressure Plasma Spraying) with a thermal spray gun. ..

In the top coat layer forming step S120, the top coat layer 120 containing ceramic is formed on the surface of the rotor blade body 70. The top coat layer forming step S120 is carried out after the bond coat layer forming step S110. In the top coat layer forming step S120, the top coat layer 120 is laminated on the bond coat layer 110 formed in the bond coat layer forming step S110. In the top coat layer forming step S120, a thermal spraying method is used. Therefore, in the top coat layer forming step S120 of the present embodiment, the top coat layer 120 is formed by spraying the sprayed particles on the surface of the bond coat layer 110 formed on the rotor blade body 70. The top coat layer forming step S120 includes a first dense layer forming step S121, a pore layer forming step S122, and a second dense layer forming step S123.

The first dense layer forming step S121 is carried out after the bond coat layer forming step S110. In the first dense layer forming step S121, the first dense layer 121 is formed on the bond coat layer 110. In the first dense layer forming step S121, suspension plasma spraying is performed to form the first dense layer 121. In the first dense layer forming step S121, suspension plasma spraying is performed by inclining the thermal spray gun with respect to the surface of the rotor blade body 70 by a predetermined inclination angle α. Suspension plasma spraying is a thermal spraying method in which a suspension in which fine sprayed particles are dispersed is supplied into a plasma jet to form a coating film. The distance between the injection hole of the thermal spray gun and the surface of the rotor blade body 70 to be sprayed is shorter in the first dense layer forming step S121 than in the pore layer forming step S122.

The fine sprayed particles preferably have a particle size of 0.1 μm or more and 1.0 μm or less. Carriers used in suspensions include, for example, water and ethanol. For the suspension plasma spraying, a thermal spray gun of the axial flow internal supply system may be used as the suspension supply method for the plasma jet, or an external supply system thermal spray gun may be used.

The pore layer forming step S122 is carried out after the first dense layer forming step S121. In the pore layer forming step S122, the intermediate pore layer 122 is formed on the first dense layer 121. In the pore layer forming step S122, suspension plasma spraying is performed to form the intermediate pore layer 122. In the pore layer forming step S122, the thermal spray gun is separated from the rotor blade body 70 to spray the thermal spray particles as compared with the first dense layer forming step S121. In the pore layer forming step S122, first, thermal spraying is performed while moving the thermal spray gun so as to gradually move away from the thermal spraying distance in the first dense layer forming step S121. After that, when the intermediate pore layer 122 is formed to about half the desired film thickness of the intermediate pore layer 122, the thermal spraying distance is gradually brought closer to the thermal spraying distance in the second dense layer forming step S123. Finally, when the intermediate pore layer 122 having a desired film thickness is formed, the thermal spraying gun is moved so that the thermal spraying distance matches the thermal spraying distance in the second dense layer forming step S123.

The second dense layer forming step S123 is carried out after the pore layer forming step S122. The second dense layer forming step S123 forms the second dense layer 123 on the intermediate pore layer 122. In the second dense layer forming step S123, suspension plasma spraying is performed to form the second dense layer 123. In the second dense layer forming step S123, the thermal spray gun is brought closer to the rotor blade body 70 than in the pore layer forming step S122, and the thermal spray particles are sprayed. The second dense layer forming step S123 of the present embodiment is carried out under the same conditions as the first dense layer forming step S121. Therefore, in the second dense layer forming step S123, the thermal spray gun is inclined by a predetermined inclination angle α with respect to the surface of the rotor blade main body 70, and thermal spraying is performed by suspension plasma spraying. The distance between the injection hole of the thermal spray gun and the surface of the rotor blade body 70 to be sprayed is shorter in the second dense layer forming step S123 than in the pore layer forming step S122.

The adjusting step S130 is carried out after the second dense layer forming step S123. The adjustment step S130 adjusts the surface condition of the heat shield coating 100. Specifically, in the adjustment step S130, the surface of the top coat layer 120 is slightly scraped to adjust the film thickness of the heat shield coating 100, or the surface is made smoother. By this adjustment step S130, for example, the thermal conductivity to the moving blade 7 can be reduced. In the adjusting step S130 of this embodiment, the surface of the second dense layer 123 is scraped by several μm to smooth the surface of the topcoat layer 120 and adjust the film thickness.

According to the heat shield coating 100, the heat shield coating forming method S100, and the moving blade 7 as described above, the intermediate pore layer 122 is formed between the first dense layer 121 and the second dense layer 123. Heat input to the topcoat layer 120 in the thickness direction is blocked by the intermediate pore layer 122. As a result, the thermal conductivity of the topcoat layer 120 can be further reduced. By forming the first dense layer 121 on the side of the top coat layer 120 that is in close contact with the bond coat layer 110 on the rotor blade body 70 side, the adhesion to the bond coat layer 110 can be ensured. Further, in the top coat layer 120, the second dense layer 123 is formed on the surface side, so that the erosion resistance can be ensured. As a result, the heat shielding effect can be enhanced while suppressing the deterioration of the erosion resistance of the heat shielding coating 100.

Specifically, the point that the presence of the intermediate pore layer 122 reduces the thermal conductivity will be described with reference to FIG. FIG. 5 is a diagram obtained by simulation of the relationship between the thermal conductivity and the porosity of the topcoat layer 120. As shown in FIG. 6, in the top coat layer 120, the larger the porosity, the smaller the thermal conductivity in the top coat layer 120. More specifically, as the porosity increases from 0% to 15%, the thermal conductivity decreases by about 10%. Therefore, it can be seen that the thermal conductivity of the topcoat layer 120 can be reduced by forming the intermediate pore layer 122 having a high porosity between the first dense layer 121 and the second dense layer 123.

Further, by setting the porosity in the intermediate pore layer 122 to 10% or more and 20% or less, the effect of inhibiting heat input in the thickness direction by the first vertical division C1 and the second vertical division C2 becomes large. As a result, the thermal conductivity of the topcoat layer 120 can be significantly reduced without significantly reducing the erosion resistance of the intermediate pore layer 122.

Further, a vertically split C formed diagonally in the top coat layer 120 is formed like the first vertical split C1 and the second vertical split C2. Therefore, the heat input in the thickness direction in the first dense layer 121 is hindered by the first vertical split C1 extending diagonally. Similarly, the heat input in the thickness direction in the second dense layer 123 is hindered by the second vertical split C2 extending diagonally. Therefore, the thermal conductivity in the topcoat layer 120 can be reduced by the first vertical division C1 and the second vertical division C2. On the other hand, the second dense layer 123 is formed on the surface side of the top coat layer 120. By forming the second dense layer 123 so densely that the vertically split C is formed, it is possible to suppress a decrease in erosion resistance. As a result, the heat shielding effect can be enhanced while suppressing the deterioration of the erosion resistance on the surface side of the heat shielding coating 100.

Specifically, the point that the thermal conductivity is lowered by inclining the vertical division C will be described with reference to FIG. FIG. 6 is a diagram obtained by simulation of the relationship between the thermal conductivity of the top coat layer 120 in which the vertical division C is formed and the inclination angle α of the vertical division C. As shown in FIG. 6, in the top coat layer 120, the smaller the inclination angle α of the vertical division C, the smaller the thermal conductivity in the top coat layer 120. More specifically, the thermal conductivity is 25% or more when the inclination angle α of the vertical division C is 60 ° as compared with the state where the vertical division C is not inclined (when the inclination angle α is 90 °). descend. Therefore, it can be seen that the thermal conductivity in the top coat layer 120 can be lowered by making the vertical division C slanted.

Further, since the topcoat layer 120 is formed by suspension plasma spraying, the particle size of the sprayed particles forming the topcoat layer 120 becomes smaller than that of atmospheric plasma spraying (APS: atmospheric plasma spraying). As a result, the first dense layer 121 and the second dense layer 123 can have a very dense structure. Therefore, it is possible to improve the adhesion of the first dense layer 121 to the bond coat layer 110 and the adhesion between each layer of the top coat layer 120.

Further, since all of the first vertical division C1 and the second vertical division C2 are inclined in the same direction, the thickness direction is extended over a wide area in the surface direction of the first dense layer 121 and the second dense layer 123. Heat input is inhibited. As a result, the thermal conductivity of the topcoat layer 120 can be reduced over a wide range.

Further, the inclination angle α of the first vertical division C1 and the second vertical division C2 is 45 ° or more and 80 ° or less. As the inclination angle α becomes smaller, the effect of inhibiting heat input in the thickness direction by the first vertical division C1 and the second vertical division C2 becomes large. As a result, the thermal conductivity of the topcoat layer 120 can be significantly reduced. Further, by setting the inclination angle α of the first vertical division C1 and the second vertical division C2 to 45 degrees or more, it becomes difficult for the sprayed particles to adhere to the surface when the first dense layer 121 and the second dense layer 123 are formed. Can be suppressed. Therefore, it is possible to further suppress a decrease in the production efficiency of the top coat layer 120.

(Other variants of the embodiment)
Although the embodiments of the present invention have been described in detail with reference to the drawings, the configurations and combinations thereof in the respective embodiments are examples, and the configurations are added or omitted within a range not deviating from the gist of the present invention. , Replacement, and other changes are possible. Further, the present invention is not limited to the embodiments, but only to the scope of claims.

In the above embodiment, the first vertical division C1 and the second vertical division C2 have an inclined structure, but the top coat layer 120 is not limited to such a structure. For example, as shown in FIG. 7, a top coat layer 120A of a heat shield coating 100A having a structure having a vertical division C (vertical division that is not inclined) extending perpendicularly to the surface direction may be formed. .. Therefore, the first vertical division C1 of the first dense layer 121A and the second vertical division C2 of the second dense layer 123A extend in the direction perpendicular to the surface of the top coat layer 120A.

Further, in the heat shield coating forming method S100 of the present embodiment, the bond coat layer forming step S110 may not be carried out. For example, the bond coat layer 110 may be formed by another method, or the bond coat layer 110 itself may not be formed. When the bond coat layer 110 is not formed, the ceramic layer may be formed directly on the surface of the rotor blade body 70.

Further, the high temperature member is not limited to the moving blade 7, and may be a member exposed to high temperature. As the high temperature member, for example, the present invention may be applied to members such as a nozzle and a cylinder constituting the stationary blade 8 of the gas turbine 1 and the combustor 3. Further, the high temperature member may be a member other than the gas turbine 1 that is exposed to a high temperature. For example, the high temperature member may be a member exposed to a high temperature environment in a gas engine.

Further, the intermediate pore layer 122 is not limited to a structure in which the vertical split C is not completely formed and only the pores P are formed. The intermediate pore layer 122 may have some vertical splits C formed as long as the porosity is sufficiently large. Similarly, the first dense layer 121 and the second dense layer 123 may have some pores P formed as long as the vertical split C is formed.

Further, the extending direction of the vertical division such as the first vertical division C1 and the second vertical division C2 is not limited to the extending direction of the virtual straight line connecting the base end and the tip end as described above. Absent. The extending direction of the vertical division may be the extending direction of the approximate straight line obtained by obtaining an approximate straight line from the vertically divided vertical division by image analysis or the like.

Further, the first vertical division C1 and the second vertical division C2 need only be inclined, and are not limited to being inclined in the same direction over the entire area. The inclination angle α of the vertical split C may be different between the surface side of the ceramic layer and the moving blade body 70 side. That is, for example, the vertical division may be inclined at different angles in the middle of the extending direction as long as it is inclined in the same direction. Therefore, in the first vertical division C1 and the second vertical division C2, for example, the inclination angle α in the region near the surface of the top coat layer 120 is larger than the inclination angle α in the region close to the surface of the rotor blade body 70. It may be formed small.

Further, in the present embodiment, the structure is such that the inclination angles α of the first vertical division C1 of the first dense layer 121 and the second vertical division C2 of the second dense layer 123 are the same, but the first dense layer 121 and the second The dense layer 123 is not limited to such a structure. Therefore, the inclination angle α of the first vertical division C1 with respect to the surface of the top coat layer 120 and the inclination angle α of the second vertical division C2 with respect to the surface of the top coat layer 120 may be different. At this time, it is preferable that the inclination angle α of the first vertical division C1 is smaller than the inclination angle α of the second vertical division C2.

Further, in the present embodiment, the distribution ratio of the vertical division C per 1 mm of the first dense layer 121 and the second dense layer 123 is the same, but the first dense layer 121 and the second dense layer 123 have such a structure. It is not limited to. For example, the distribution rate of the vertical division C per 1 mm of the second dense layer 123 may be larger or smaller than the distribution rate of the vertical division C per 1 mm of the first dense layer 121.

Further, in the present embodiment, the porosities of the first dense layer 121 and the second dense layer 123 are the same, but the first dense layer 121 and the second dense layer 123 are not limited to such a structure. .. For example, the porosities of the first dense layer 121 and the second dense layer 123 may be different from each other as long as they are lower than the porosity of the intermediate pore layer 122.

Further, in the vertical division C of the present embodiment, as in the case of the first vertical division C1 and the second vertical division C2, an interval is provided by the intermediate pore layer 122 in the vicinity of the middle in the thickness direction in one top coat layer 120. It is formed like this. As described above, the vertically split C is not limited to the structure in which the ceramic layer is continuous from the surface facing the rotor blade body 70 side to the surface. Therefore, the vertically split C may extend intermittently in the thickness direction in one ceramic layer. Therefore, the first vertical division C1 and the second vertical division C2 are not limited to the continuously extending structure as in the present embodiment. For example, the first vertical splits C1 may be formed in the first dense layer 121 at intervals in the thickness direction. Similarly, the second vertical split C2 may be formed in the second dense layer 123 at intervals in the thickness direction.

Further, in the pore layer forming step S122 of the present embodiment, the thermal spraying gun is moved so as to gradually change (eliminate) the thermal spraying distance, but the present invention is not limited to moving the thermal spraying gun in this way. .. For example, in the pore layer forming step S122, the spraying gun may be moved so as to rapidly change from the spraying distance in the first dense layer forming step S121 to the target spraying distance in the pore layer forming step S122.

Moreover, the thermal spraying conditions mentioned in each step are examples, and are not limited. The thermal spraying conditions may be appropriately set according to the apparatus used, the type of thermal spraying particles to be targeted, and the like.

1 ... Gas turbine 2 ... Compressor 3 ... Combustor 4 ... Turbine body 5 ... Rotor 6 ... Casing 7 ... Moving blade 70 ... Moving blade body 71 ... Blade body 72 ... Platform 73 ... Wing root 74 ... Shroud 8 ... Turbine blade A ... Compressed air G ... Combustor gas 100 ... Heat shield coating 110 ... Bond coat layer 120 ... Top coat layer 121 ... First dense layer C1 ... First vertical division α ... Tilt angle 122 ... Intermediate pore layer P ... Pore 123 ... Second dense layer C2 ... Second vertical split S1 ... Manufacturing method of high temperature member S10 ... Turbine body preparation process S20 ... Heat shield coating forming process S100 ... Heat shielding coating forming method S110 ... Bond coat layer forming process S120 ... Top coat Layer forming step S121 ... First dense layer forming step S122 ... Pore layer forming step S123 ... Second dense layer forming step S130 ... Adjusting step C ... Vertical split

Claims (6)

Formed on a heat resistant alloy substrate, with a ceramic layer containing ceramic,
The ceramic layer is
The first dense layer and
An intermediate pore layer laminated on the first dense layer and having a higher density than the first dense layer and a large number of pores formed.
The laminated to the intermediate pore layer, have a, a second dense layer density is less than the intermediate pore layer,
In the first dense layer, the first vertical division extending in the thickness direction is dispersed in the plane direction.
In the second dense layer, the second vertical division extending in the thickness direction is dispersed in the plane direction.
The first vertical division and the second vertical division are thermal barrier coatings that extend at an angle with respect to the surface of the ceramic layer . The porosity changes continuously at the first boundary portion which is the boundary portion between the intermediate pore layer and the first dense layer and the second boundary portion which is the boundary portion between the intermediate pore layer and the second dense layer. The heat shield coating according to claim 1. The heat-shielding coating according to claim 1 or 2, wherein the porosity of the intermediate pore layer is 10% or more and 20% or less. The heat-shielding coating according to any one of claims 1 to 3, wherein the porosity of the first dense layer and the second dense layer is 10% or less and 5% or more. The heat shield according to any one of claims 1 to 4 , wherein the inclination angle of the first vertical division with respect to the surface of the ceramic layer and the inclination angle of the second vertical division with respect to the surface of the ceramic layer are different. coating. Heat resistant alloy base material and
A high-temperature member comprising the heat-shielding coating according to any one of claims 1 to 5, which is formed on the heat-resistant alloy base material.

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