JP4434667B2 - Manufacturing method of heat shielding ceramic coating parts - Google Patents

Description

The present invention relates to a process for producing a heat-shielding ceramic coating unit products for use in equipment used in a high temperature range, such as a gas turbine for power generation.

As a heat-resistant component used in high-temperature areas such as gas turbine blades and combustion cylinders, it has excellent high-temperature oxidation resistance and high-temperature corrosion resistance such as MCrAlY (M is Co or Ni) on the surface of a Ni-based heat-resistant alloy substrate. What formed the heat-shielding ceramic sprayed coating through the base sprayed coating is used widely. Generally, this ceramic sprayed coating is stabilized by adding MgO, CaO, Y ₂ O ₃ or the like to ZrO ₂ and is usually formed to a thickness of about several hundred μm by plasma spraying. is there.

  However, even in a heat-resistant component provided with the above-described heat-shielding ceramic sprayed coating, interfacial delamination occurs between the ceramic sprayed coating and the base sprayed coating due to repeated thermal shock (heating-cooling thermal cycle). There was a problem that sufficient high-temperature durability could not be obtained under harsh use conditions. In particular, in the case of a gas turbine, there is a tendency to increase the operating temperature in order to improve the power generation efficiency, and accordingly, there is a strong demand for improving the high temperature durability of each component and extending the life. In addition, when the thickness of the ceramic sprayed coating is increased in order to alleviate the thermal effect on the base material, the internal stress due to thermal shock increases, so that the above-described interface peeling is more likely to occur.

Therefore, in recent years, it has been proposed to form a columnar structure due to cracks in the thickness direction (longitudinal cracks) in the heat-shielding ceramic sprayed coating as a means for coping with the above demand. This is due to the difference in linear expansion coefficient between the ceramic sprayed coating, the base sprayed coating and the heat-resistant alloy substrate (linear expansion coefficient: stabilized ZrO ₂ sprayed layer: 10 to 11 × 10 ⁻⁶ / K, Ni-base heat-resistant alloy and MCrAlY alloy ... 16 × 10 ^-6 / K), cracks are formed in advance on the ceramic sprayed coating, and the cracks absorb the difference in expansion and contraction associated with the thermal cycle. It is to let you.

Therefore, as a method of forming the columnar structure of the thermal shielding ceramic sprayed coating according to the conventional proposal, a method of forming a stabilized ZrO ₂ layer by electron beam deposition and oxygen ion irradiation (Patent Document 1), plasma spraying A method of locally irradiating the surface of the stabilized ZrO ₂ layer deposited by the pulse laser as a post-treatment (Patent Document 2), and by controlling the spraying conditions when forming the stabilized ZrO ₂ layer by plasma spraying There is a method (Patent Document 3) in which cracks are generated for each sprayed single layer (one pass).
JP-A-9-67632 Japanese Patent Laid-Open No. 9-327779 Japanese Patent No. 2710075

However, the method of forming a film by electron beam evaporation and oxygen ion irradiation is expensive and inefficient because the film forming speed is slow, and the film thickness is 300 μm or more by adjusting the processing atmosphere. There was a difficulty that it was difficult to make. Further, in the method in which the pulsed laser is locally irradiated after the film formation, since the formed crack reaches the entire thickness of the stabilized ZrO ₂ layer, the corrosive high temperature atmosphere is directly passed through the crack to the base sprayed coating. There is a drawback that the heat shielding function inherent to the stabilized ZrO ₂ layer is not fully exhibited and the base material is likely to be thermally deteriorated. Furthermore, the method of controlling the conditions during plasma spraying has the disadvantage that complicated control operations are required, such as changing the temperature for each spraying, and the formed ZrO ₂ layer is stabilized from the substrate side. Although it is set in the middle of the thickness, it is inferior in adhesion between the stabilized ZrO ₂ layer and the base sprayed coating, and cracks are enlarged during use and easily develop into cracks penetrating the stabilized ZrO ₂ layer. As a result, there was a problem that the base sprayed coating was directly affected by the corrosive high temperature atmosphere as described above.

The present invention relates to a method in view of the above circumstances, the heat shield ceramic coating component for use in equipment used in a high temperature range, such as gas turbine for power generation, which can be easily produced shall comprise a very good thermal shock resistance The purpose is to provide.

To achieve the above object, a manufacturing method of the heat shield ceramic coating component according to a first aspect of the invention, the surface of the metal substrate, MCrAlY (M is Co or Ni) and the base thermal spray coating made of an alloy, ZrO ₂ After the thermal spraying ceramic sprayed coating mainly composed of the above is formed by sequential plasma spraying, the surface of the thermally shielded ceramic sprayed coating is irradiated with a laser beam to thereby apply the sprayed coating to the surface layer portion of the thermally shielded ceramic sprayed coating. A glass layer in the range of 2 to 30% of the thickness is formed, and a number of vertical cracks are formed on the sprayed coating from the surface to the thickness direction at an average depth in the range of 30 to 80% of the thickness of the sprayed coating. It is characterized by that.

As a preferred embodiment of the method for producing a heat shielding ceramic coating component according to the invention of claim 1, in the invention of claim 2, longitudinal cracks of the thermal shielding ceramic sprayed coating are formed at a density of 1 to 5 / mm. configuration, 10 to 500 [mu] m thickness of the undercoat sprayed coating made of MCrAlY alloys invention of 請 Motomeko 3, the thickness of the 10~5000μm configuration of the heat shield ceramic sprayed coating, the heat shield ceramic sprayed coating in the invention of claim 4 It adopts structure that the average surface roughness Ra less 7.5 [mu] m, respectively.

Further, according to a fifth aspect of the present invention, in the method for manufacturing a heat-shielding ceramic coating component according to any one of the first to third aspects, the laser beam is supplied with a power density of 40 to 200 W / mm ² and an energy density of ^{2 to 5} J / mm. ² range, and the product of the power density and energy density are configured to irradiation under the condition that the ^{180W / mm 2 · J / mm} 2 or more. According to a sixth aspect of the present invention, in the method for manufacturing a shielding ceramic coating component of the fifth aspect , the laser beam is irradiated in a top flat type.

According to the manufacturing method of the first aspect of the present invention , as a heat-shielding ceramic coating component used in a device used in a high temperature region such as a gas turbine for power generation, an undercoat sprayed on the surface made of an MCrAlY (M is Co or Ni) alloy. A heat-shielding ceramic sprayed coating mainly composed of ZrO ₂ is formed through the coating, and the heat-shielding ceramic sprayed coating has a number of vertical cracks reaching a specific depth from the surface in the thickness direction. It is possible to easily manufacture a thermal barrier ceramic sprayed coating that is unlikely to cause interface peeling due to impact at low cost . In addition, due to the densification of the surface layer part of this coating component, the influence of corrosive high temperature atmosphere is less likely to reach the base, thermal performance such as high temperature durability, high temperature corrosion resistance, high temperature oxidation resistance, and erosion resistance excellent characteristics Ru long life der.

According to the manufacturing method of the second aspect of the present invention , since the longitudinal cracks of the thermal shielding ceramic sprayed coating are present at a specific density as the above-described thermal shielding ceramic coating component, one having improved thermal shock resistance can be obtained. .

According to the manufacturing method of the third aspect of the present invention , since the base sprayed coating and the heat shielded ceramic sprayed coating are in a specific thickness range as the heat shielding ceramic coating component, sufficient thermal shock resistance can be achieved with a small material cost. which comprises a can be obtained.

According to the manufacturing method of the fourth aspect of the present invention , since the surface roughness of the thermal shielding ceramic sprayed coating is not more than a specific value as the above-described thermal shielding ceramic coating component, In addition, the coating surface is excellent in wear resistance under use conditions in which solid particles flying at high speed collide with the surface, and a component having improved durability as a component used under such use conditions can be obtained. .

According to the manufacturing method according to the invention of claim 5, and a benzalkonium it is irradiated with the laser beam at a specific power density and energy density, facilitating a long-life heat shielding ceramic coating component excellent in the thermal performance of And can be manufactured reliably.

According to the manufacturing method of the invention of claim 6 , since the laser beam is irradiated in a top flat type, the film properties can be homogenized and the processing efficiency is improved, and the surface to be processed is curved. And stable processing conditions can be ensured.

FIG. 1 schematically shows a cross-sectional structure of a surface layer portion of a heat-shielding ceramic coating part obtained by the production method of the present invention, and (A) shows the number of cycles until a film area is peeled 50% in a thermal shock test described later. 9 is a cross-sectional structure in which an evaluation of 9 was obtained, and (B) is a cross-sectional structure in which an evaluation of 18 cycles was obtained.

1 (A) and 1 (B), 1 is a metal substrate, 2 is a base sprayed coating made of an MCrAlY (M is Co or Ni) alloy provided on the metal substrate 1, and 3 is the base sprayed coating 2 A heat-shielding ceramic sprayed coating mainly composed of ZrO ₂ provided on the surface, and a surface layer portion of the heat-shielding ceramic sprayed coating 3 has a glass layer 4 which is melted and densified, and the surface of the ceramic sprayed coating 3 A large number of vertical cracks 5 extending in the thickness direction are formed. Thus, these vertical cracks 5 have a depth that does not reach the interface with the base sprayed coating 2.

  In such a heat-shielding ceramic coating component, since the heat-shielding ceramic sprayed coating 3 has a columnar structure due to vertical cracks 5..., The ceramic sprayed coating when subjected to a thermal shock during use as a component such as a gas turbine for power generation. Even if there is a difference in expansion / contraction due to the difference in linear expansion coefficient between the thermal spray coating 3 and the base sprayed coating 2 and the metal substrate 1, the internal stress is absorbed and relaxed at the longitudinal cracks 5 ... constituting the columnar structure. Since the vertical cracks 5 ... do not reach the base sprayed coating 2, the adhesion between the base sprayed coating 2 and the ceramic sprayed coating 3 is good, so that the interfacial delamination between the two sprayed coatings 2 and 3 can be effectively suppressed. In addition, since the vertical crack 5 from the surface side of the ceramic sprayed coating 3 is difficult to expand in the depth direction and does not develop into a crack penetrating the entire ceramic sprayed coating 3, the base sprayed coating 2 has a vertical crack 5. Directly through Not be affected by the corrosive high temperature atmosphere, excellent high-temperature durability can be obtained even under severe use conditions have.

Therefore, in the manufacturing method of the heat shielding ceramic coating component of the present invention, it is technically difficult to arrange all the vertical cracks 5 ... formed in the heat shielding ceramic sprayed coating 3 at a constant depth. vertical cracks 5 ... average depth and 30 to 80% of the depth range of the sprayed coating thickness, and vertical cracks 5 ... a density of 1 to 5 present / mm. That is, when the average depth of the vertical cracks 5 is less than 30% of the thickness of the thermal spray coating, absorption relaxation of internal stress due to the vertical cracks 5 is insufficient, and conversely, the average depth is the thermal spray. When it exceeds 80% of the coating thickness, the base sprayed coating 2 is likely to be directly affected by the corrosive high temperature atmosphere through the vertical cracks 5 ..., and both the high temperature durability deteriorates. On the other hand, if the density of longitudinal cracks 5 is less than 1 / mm, the absorption relaxation of internal stress is insufficient, and if it exceeds 5 / mm, there is an effect of relaxing internal stress, but the actual use environment Peeling of the coating surface due to thermal shock is likely to occur.

The optimum value of the thickness of the base sprayed coating 2 made of MCrAlY alloy in the heat-shielding ceramic coating part manufactured according to the present invention varies depending on the type of the part, but generally it is preferably in the range of 10 to 500 μm, and too thin. High temperature oxidation resistance and high temperature corrosion resistance become insufficient, and if it is too thick, no further effect can be expected, which is uneconomical. Further, the optimum value of the thickness of the heat-shielding ceramic sprayed coating 3 also varies depending on the type of the part, but generally the range of 10 to 5000 μm is preferable, and if it is too thin, the thermal shock resistance is insufficient. Even if it is too thick, the thermal shock resistance deteriorates due to an increase in internal stress due to thermal shock. Although depending on the spraying conditions, the diameter of the sprayed particles is generally around 50 μm, and the thickness of the single layer formed by one spraying (one pass) is 30 μm inside or outside, so that the base spraying with a thickness larger than that is performed. The coating 2 and the heat-shielding ceramic spray coating 3 are repeatedly sprayed until the required thickness is reached.

Here, as the ceramic material of the thermal shielding ceramic sprayed coating 3, ZrO ₂ stabilized by adding MgO, CaO, Y ₂ O ₃ or the like is preferably used. Moreover, as the metal substrate 1, a Ni-based heat-resistant alloy such as Inconel is suitable.

  With respect to the glass layer 4 in the surface layer portion of the ceramic sprayed coating 3, the formation of the glass layer 4 greatly increases the generation of the vertical cracks 5 and the surface properties of the coating in the laser post-processing for forming the vertical cracks 5 to be described later. Has been found to be involved. Such a glass layer 4 has a general tendency to increase in thickness with an increase in power density and energy density in laser post-treatment, but the average thickness is 2-30 of the thickness of the thermal shielding ceramic sprayed coating 3. % Should be in the range. That is, if the glass layer 4 is too thin, the vertical cracks 5. On the other hand, if the glass layer 4 is too thick, the thermal spray coating 3 is liable to be peeled off in the laser post-treatment, and the wear resistance is deteriorated due to the surface of the coating being wavy.

  The above-mentioned wear resistance means the film strength under use conditions in which solid particles flying at high speed collide with the surface, such as a gas contact portion in a power generation gas turbine. That is, in a gas contact portion such as a moving blade or stationary blade of a turbine in a power generation gas turbine, or an inner peripheral portion of a casing, high-temperature and high-pressure gas passes through a narrow flow gap at high speed. A large amount of solid fine particles such as dust and dust continuously collide and rub against the surface of the contact portion, and the surface of the contact portion is scraped off and easily worn. Therefore, in order to ensure excellent durability as a component used in such a gas contact portion, in addition to enhancing the thermal shock resistance by the heat shielding ceramic coating, it is extremely important to improve the wear resistance of the coating layer. It becomes important.

  Therefore, in order to obtain good wear resistance, it is preferable to set the average surface roughness (Ra) of the heat shielding ceramic sprayed coating 3 to 7.5 μm or less. That is, when the average surface roughness (Ra) exceeds 7.5 μm, the coating wears remarkably under use conditions in which solid particles flying at high speed strike, and the heat shielding ceramic used under such conditions Durability as a coating part becomes insufficient. The surface properties of the coating vary depending on the type of sprayed powder, particle size, supply rate, current during spraying, voltage, gas type, flow rate, spray gun moving speed, laser output during laser post-processing, processing speed, etc. Therefore, in manufacturing the coating, it is necessary to control the overall process conditions so as to keep the surface roughness properly together with the above-described thermal shock resistance. This average surface roughness (Ra) is a value measured by a stylus type surface roughness meter.

In the method for producing a heat-shielding ceramic coating component of the present invention, a base sprayed coating 2 made of MCrAlY (M is Co or Ni) alloy and a heat-shielding ceramic sprayed coating 3 mainly composed of ZrO ₂ are formed on the surface of the metal substrate 1. Are sequentially formed by plasma spraying, and then the surface of the heat shielding ceramic sprayed coating 3 is irradiated with a laser beam at an appropriate power density and energy density as a post-treatment. That is, by this laser beam irradiation, the surface layer portion of the thermal shielding ceramic sprayed coating 3 is heated and melted, and the structure becomes dense due to the bonding force between the molten particles. Along with the solidification shrinkage due to cooling and solidification, a number of vertical cracks 5... In the thickness direction from the surface to the ceramic sprayed coating 3 are formed in a mesh shape when viewed from the surface.

As described above, the laser beam to be irradiated has a high power density and a low energy density in setting the average depth of the vertical cracks 5 to 30 to 80% of the layer thickness. However, since it is necessary to prevent the thermal spray coating from being peeled off and the surface property from being deteriorated due to the laser post-treatment, the power density ranges from 40 to 200 W / mm ² and the energy density ranges from ^{2 to 5} J / mm ^2. Irradiation conditions in which the product of density is 180 W / mm ² · J / mm ² or more are suitable. That is, if the power density is less than 40 W / mm ² and the energy density is less than ² J / mm ² , the generation of vertical cracks 5 is insufficient, and if the power density exceeds 200 W / mm ² , the laser heat input is excessive. Therefore, it is difficult to form a sound coating, and when the energy density exceeds 5 J / mm ² , the thermal spray coating is peeled off or the surface property is deteriorated. In addition, in order to generate a predetermined vertical crack in the film, laser heat input of a certain level or more is required, so the product of the power density and the energy density is preferably 180 W / mm ² · J / mm ² or more. . In order to obtain particularly high thermal shock resistance and excellent wear resistance, it is recommended to set the power density in the range of 120 to 200 W / mm ² and the energy density in the range of ³ to 5 J / mm ^2. .

  As shown in FIG. 2, the laser post-treatment is performed by irradiating the surface of the heat shielding ceramic sprayed coating 3 provided on the metal substrate 1 via the MCrAlY alloy base sprayed coating 2 while relatively moving the laser beam 6. do it. Therefore, it is desirable to irradiate the laser beam 6 as a top flat type converted by a kaleidoscope or the like. This is because the top hat type laser beam 6 can irradiate a wide area evenly in one scan, so that the film properties can be homogenized and the processing efficiency can be improved. Even if the surface to be processed is curved and the distance from the emission position of the laser beam 6 is changed by linear relative movement, the power density on the irradiated surface hardly changes, and stable processing conditions can be secured. . The type of laser to be used is not particularly limited, but a continuous wave YAG laser is suitable from the viewpoint of easy handling and control.

In addition, although the above-mentioned laser post-treatment can be performed as it is on the heat-shielding ceramic sprayed coating 3 after the thermal spray formation, if necessary for the purpose of improving the adhesion between the thermal sprayed coatings 2 and 3 and the substrate 1, the ceramic sprayed coating is applied. The film 3 may be subjected to laser post-treatment after being subjected to vacuum diffusion heat treatment. However, when this vacuum diffusion heat treatment is performed, the film surface becomes black and heat absorption in the next laser post-treatment increases, so that the energy density of the laser beam 6 is set to prevent film peeling in the laser post-treatment. It is preferable to set it relatively small, and it is recommended that it is preferably 3 J / mm ² or less.

The heat-shielding ceramic-coated part obtained by the present invention is used in a part where a large thermal shock is applied to equipment used in a high temperature range, and there are no particular restrictions on its use and part type, but in particular a gas for power generation. It is suitable as a part used in a gas contact portion in a turbine, for example, a moving blade or stationary blade of a turbine, an inner peripheral portion of a casing, or the like.

[Formation of base sprayed coating and heat shielding ceramic sprayed coating]
Using a plurality of Inconel alloy plates of 25 mm in length and width and 5 mm in thickness as metal substrates, a base sprayed coating made of a CoNiCrAlY alloy is formed on each of these blasted surfaces (# 24 alumina powder) by low pressure plasma spraying. this by atmospheric plasma spraying over the base thermal spray coating to form a heat shielding ceramic sprayed coating 3 made of ZrO ₂ -Y ₂ O _3, to prepare a test piece. The following spraying powder and plasma spraying conditions are shown in the following Tables 1 to 3.

[Laser post-processing]
About each test piece which formed the said foundation | substrate sprayed coating and the heat-shielding ceramic sprayed coating, the laser post-process was performed on the surface of the ceramic sprayed coating by various conditions with the YAG laser irradiation apparatus. And after observing the cross-sectional structure of the sprayed coating part in each metal substrate after treatment with a microscope, the density and depth of longitudinal cracks, the film thickness ratio of the glass layer of the surface layer part in the ceramic sprayed coating, and the surface state evaluated. Further, thermal shock resistance and wear resistance tests were performed on each test piece after laser post-treatment under the same conditions as these. These results are shown in Table 4 below together with laser post-treatment conditions. However, test piece No. Regarding 12, 13, 16, and 17, remarkable surface irregularities and peeling were caused by laser post-processing, and therefore the density and depth of vertical cracks and the film thickness ratio of the glass layer were not measurable. Judgment was also omitted for the thermal shock resistance and wear resistance tests. In Table 4, the P density is the power density, the E density is the energy density, the unit of the product of the P density and the E density is W / mm ² · J / mm ² , the density and depth of the vertical crack and the film thickness ratio of the glass layer are All are average values, and the reference example means a test piece not subjected to laser post-treatment.

  The laser beam is a top hat type with a beam spot on the irradiation surface of 5 mm □ and an irradiation pitch (interval of laser scanning lines) of 4 mm, and the energy density is three stages of laser output (3.5 KW, 2.0 KW, 1. 0 KW) and the irradiation speed (10 to 700 mm / sec). The thermal shock resistance is 50% of the coating area by loading a test piece in an electric furnace, holding it for 2 minutes after the furnace temperature reaches 1303 ° K, and taking it out immediately in ice water for one cycle. The number of cycles until the peeling occurred was examined.

For abrasion resistance, a test piece prepared by subjecting an inconel alloy plate of 50 mm in length, 60 mm in width, and 5 mm in thickness to blasting, base spraying, and thermal shielding ceramic spraying in the same manner as described above, 30 g of 24 alumina powder was sprayed at an injection speed of 114 m / sec, and the weight loss of the test piece was investigated.

From Table 4, the density (average) of vertical cracks provided in the heat-shielding ceramic sprayed coating is 1 to 5 / mm, and the depth (average) of vertical cracks is within the range of 30 to 80% of the ceramic sprayed coating. The test pieces (Nos. 2 to 5, 9 to 11, 15) exhibit high thermal shock resistance of 7 cycles or more, and in particular, the power density in laser post-processing is 140 W / mm ² and the energy density is 3 to 5 J / mm. ^In the test piece (Nos. 3 to 5) designated as ² , extremely excellent thermal shock resistance of 17 cycles or more was obtained. However, the test piece No. whose surface roughness (Ra) of the coating is greater than 7.5 μm. In No. 11, the abrasion resistance is inferior to the test piece of the reference example that has not been subjected to the laser post-treatment. This is related to the surface condition of the film. When the surface of the film becomes rough and rough, the collision of wear powder concentrates on the convex part, causing local film damage. It is thought that wear increases in a chain.

On the other hand, in the test piece (No. 1, 14) in which the density of longitudinal cracks is less than 1 / mm or the depth is less than 30% of the ceramic sprayed coating, sufficient thermal shock resistance is not obtained. . Moreover, in the test piece (No. 6, 11-13, 16, 17) set to the energy density exceeding 5 J / mm ² by the laser post-treatment, the surface roughness or peeling of the sprayed coating is caused by the laser post-treatment. Furthermore, if the product of power density and energy density is set to 180 W / mm ² · W / mm ² or more, the density of vertical cracks will be 1 / mm or more and the depth will be 30% or more of the ceramic spray coating. I know you get.

FIG. 3 shows a thermal shock resistance correlation characteristic diagram derived from the measured value of the thermal shock resistance test on the test piece subjected to the laser post-treatment in the above example, and the power density and energy density of the laser post-treatment. From this figure, it is suggested that when the power density is constant, the thermal shock resistance improves as the energy density increases, but it is possible to provide high thermal shock resistance in a region where the power density is large even if the energy density is small. In view of the fact that the energy density needs to be relatively small in order to ensure the soundness of the ceramic sprayed coating, the laser beam power density is 40 W / mm ² or more in the laser post-treatment, and the energy density is 2 to 2. 5J / mm ² and the product of the power density and the energy density should be set to be 180 W / mm ² · W / mm ² or more. It can be said that it is desirable to set 120 W / mm ² or more and the energy density to 3 to 5 J / mm ² .

FIG. 4 shows the relationship between the power density and energy density of the laser post-treatment and the vertical crack density of the thermal-shielding ceramic sprayed coating for the test piece subjected to the laser post-treatment in the above-mentioned embodiment, and is added in FIG. The broken line is the thermal shock resistant 9 cycle line (see FIG. 3). From this figure, the vertical cracks formed in the ceramic spray coating increase as the power density increases, but in the region where the power density is high, there is a peak of the vertical crack density in the range where the energy density is relatively low, and the heat resistance in FIG. As suggested by the approximation of impact 9 cycle line and vertical crack density 2.2mm ^-1 line or 2.6mm ^-1 line, the higher the vertical crack density, the higher the heat resistance in the energy density range 2-5 J / mm ^2. The impact property shows a tendency to improve.

FIG. 5 shows the relationship between the power density and energy density of the laser post-treatment and the vertical crack depth of the thermal-shielding ceramic sprayed coating for the test piece subjected to the laser post-treatment in the above embodiment. The thermal shock resistance 9 cycle line is appended with a broken line. From this figure, the depth of the vertical crack formed in the ceramic sprayed coating is greatly influenced by the energy density rather than the power density, and increases remarkably as the energy density increases. As suggested by the comparison, there is a certain degree of correlation with the thermal shock resistance, and the thermal shock resistance tends to be improved as the energy density becomes deeper in the range of ^{2 to 5} J / mm ² .

  FIG. 6 shows the relationship between the thickness of the glass layer and the depth of vertical cracks in the heat-shielding ceramic sprayed coating for the test piece subjected to laser post-treatment in the above-mentioned embodiment. As is clear from this figure, the thickness of the glass layer corresponds to the depth of the vertical crack formed to some extent, and the depth of the vertical crack tends to increase as the thickness of the glass layer increases.

  FIG. 7 shows the relationship between the surface roughness (Ra) of the coating of each test piece (Nos. 1 to 17 and Reference Example) shown in Table 4 and the wear resistance. As is apparent from this figure, the amount of wear increases sharply with the surface roughness (Ra) of 7.5 μm as the boundary and the surface state becomes rougher than that. This suggests that if the surface of the film is excessively vitrified by laser post-treatment, the surface of the film becomes rough and rough, and the film tends to drop off due to collision of wear powder. On the other hand, the film having a surface roughness (Ra) of 7.5 μm or less does not show a significant correlation between the surface roughness and the wear resistance, but the amount of wear is generally higher than the film of the reference example that has not been subjected to laser post-treatment. Is decreasing. This is because when the surface of the coating is moderately vitrified, the surface becomes smooth and less susceptible to the impact of abrasion powder. In addition, the glass layer contributes to fixing the surface of the coating, and the coating due to the collision of abrasion powder. It is considered that separation is less likely to occur.

FIG. 8 shows a test piece No. 1 subjected to laser post-treatment in the above example. 3 is an electron micrograph showing a cross-sectional structure of a sprayed coating portion 3. In this electron micrograph, the slightly lighter color portion at the bottom is the base material, the darker color portion above is the base sprayed coating of CoNiCrAlY alloy, and the uppermost portion is ZrO ₂ —Y _2. This is an O ₃ heat-shielding ceramic sprayed coating. Thus, although vertical cracks are formed in the thickness direction from the surface of the ceramic sprayed coating, the vertical cracks do not reach the interface with the base sprayed coating, and the surface layer portion of the ceramic sprayed coating is dense. It can be seen that a glass layer is formed.

The cross-sectional structure | tissue of the surface layer part of the heat-shielding ceramic coating component obtained by the manufacturing method of this invention is shown, (A) is a schematic cross section of the component by which evaluation of thermal shock property 9 cycles was obtained, (B) is the same 18th. It is a schematic cross section of the same part for which the evaluation of the cycle was obtained. It is a schematic cross section of the principal part which shows the laser post-process in manufacture of the same heat shielding ceramic coating component. It is a correlation characteristic figure which shows the relationship between the thermal shock resistance in the test piece which performed the laser post-processing in the Example of this invention, and the power density and energy density of laser post-processing. It is a correlation characteristic figure which shows the relationship between the power density and energy density of laser post-processing in the test piece which performed the laser post-processing in the Example, and the vertical crack density of a thermal-shielding ceramic sprayed coating. It is a correlation characteristic figure which shows the relationship between the power density and energy density of the laser post-processing in the test piece, and the vertical crack depth of a heat shielding ceramic sprayed coating. It is a correlation characteristic figure which shows the relationship between the thickness of the glass layer of the thermal-shielding ceramic sprayed coating in the test piece which performed the laser post-process in the Example, and the depth of a vertical crack. It is a correlation characteristic figure which shows the relationship between the surface roughness by the abrasion-resistance test of the test piece of the reference example which did not perform the laser post-process, and the amount of wear. It is an electron micrograph figure which shows the cross-sectional structure | tissue of the sprayed coating part of the small test piece which gave the laser post-process in the Example.

DESCRIPTION OF SYMBOLS 1 Metal base material 2 Ground spray coating 3 Thermal shielding ceramic spray coating 4 Glass layer 5 Longitudinal crack 6 Laser beam

Claims (6)

The surface of the metal substrate, after MCrAlY (M is the Co, or Ni) and the base thermal spray coating made of an alloy, and a heat shielding ceramic sprayed coating mainly composed of ZrO _2, was formed by sequential plasma spraying, heat shielding ceramic spray By irradiating the surface of the coating with a laser beam, a glass layer in the range of 2 to 30% of the thickness of the thermal spray coating is formed on the surface layer portion of the thermal shielding ceramic thermal spray coating, and the thermal spray is applied to the thermal spray coating from the surface. method for producing a large number of vertical cracks to form a heat shield ceramic coating components, characterized in Rukoto toward the thickness direction at an average depth of 30% to 80% range of the film thickness. The manufacturing method of the heat shielding ceramic coating component of Claim 1 which forms the vertical crack of the said heat shielding ceramic sprayed coating by the density of 1-5 pieces / mm. 10~500μm the thickness of the undercoat sprayed coating made of MCrAlY alloy, a manufacturing method of the heat shield ceramic coating component according to the thickness of the heat shield ceramic sprayed coating in claim 1 or 2 shall be the 10～5000Myuemu. Manufacturing method of the heat shield ceramic coating component according to any one of claims 1 to 3 mean surface roughness Ra of the heat shield ceramic sprayed coating shall be the following 7.5 [mu] m. The laser beam, the power density 40~200W / mm ^2, the range of the energy density 2~5J / mm ^2, and irradiated under the condition that the product of the power density and energy density is ^{180W / mm 2 · J / mm} 2 or more The manufacturing method of the heat-shielding ceramic coating component in any one of Claims 1-4 . 6. The method of manufacturing a heat-shielding ceramic coating component according to claim 5, wherein the laser beam is irradiated in a top flat type.

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