MCrAlY bonding layer alloy, alloy target ring and preparation method of MCrAlY bonding layer alloy

Abstract

The embodiment of the invention provides an MCrAlY bonding layer alloy, an alloy target ring and a preparation method of the MCrAlY bonding layer alloy. The MCrAlY bonding layer alloy comprises the following components in percentage by weight: 13 to 18 weight percent of Cr, 10 to 15 weight percent of Co, 12 to 17 weight percent of Al, 0.25 to 1.0 weight percent of Y, 0.3 to 0.9 weight percent of Hf, 0.3 to 1.0 weight percent of Re and the balance of Ni. Therefore, the bonding layer alloy has better oxidation resistance, is not easy to peel off and crack when being used as a coating, and is particularly good in performance and not easy to crack when being used for an annular target material for vacuum arc ion plating; and the material has good use performance at 1150 DEG C and a relatively high temperature, is high in yield, and is suitable for industrial production.

Description

Technical Field

[0001] The present disclosure relates to the technical field of thermal barrier coating preparation, and in particular to an MCrAlY bonding layer alloy, an alloy target ring and a preparation method thereof. Background Art

[0002] Thermal barrier coating technology is widely used in high temperature protection of turbine blades of gas turbines and aircraft engines. For example, in order to reduce the surface temperature of the hot end parts of aircraft engines and improve the oxidation resistance and corrosion resistance of the hot end parts, the surface thermal protection technology of thermal barrier coating is usually adopted. Thermal barrier coating usually consists of a ceramic layer that acts as a heat insulation and a bonding layer that alleviates the thermal expansion mismatch between the ceramic layer and the base alloy and improves the oxidation resistance and corrosion resistance of the base alloy. MCrAlY is a commonly used bonding layer material at this stage. Its composition is easy to adjust, closer to the high-temperature alloy base alloy and has slower thermal diffusion degradation. The preparation methods of MCrAlY coating mainly include low-pressure plasma spraying, electron beam physical vapor deposition, supersonic flame spraying, magnetron sputtering and vacuum arc ion plating. Among them, the coating prepared by vacuum arc ion plating technology has the characteristics of uniform thickness, low porosity, good density, high deposition efficiency, excellent metallurgical bonding between the coating and the base alloy, and low oxygen content, and is favored. With the continuous improvement of the thrust-to-weight ratio of aircraft engines, the long-term operating temperature of thermal barrier coating bonding layer materials is required to reach above 1150°C. However, the current operating temperature of MCrAlY bonding layer materials generally does not exceed 1100°C.

[0003] Therefore, the current MCrAlY bonding layer alloy, alloy target ring and preparation method thereof still need to be improved. Summary of the invention

[0004] The embodiments of the present disclosure provide an MCrAlY bonding layer alloy, an alloy target ring and a preparation method thereof to solve or alleviate one or more technical problems in the related art.

[0005] As a first aspect of an embodiment of the present disclosure, an MCrAlY bonding layer alloy is provided. The MCrAlY bonding layer alloy comprises, by weight percentage: Cr 13-18wt%, Co10-15wt%, Al 12-17wt%, Y0.25-1.0wt%, Hf0.3-0.9wt%, Re 0.3-1.0wt%, and the rest is Ni.

[0006] In a possible implementation, the MCrAlY bonding layer alloy includes, by weight percentage, Cr 15-18wt%, Co 13-15wt%, Al 13-16wt%, Y 0.25-0.6wt%, Hf 0.3-0.8wt%, Re 0.4-0.7wt%, and the remainder Ni.

[0007] Alternatively, the MCrAlY bonding layer alloy includes, by weight percentage, Cr 15-18wt%, Co 13-15wt%, Al 12-16wt%, Y 0.25-0.5wt%, Hf 0.3-0.5wt%, Re 0.5-1.0wt%, and the remainder Ni.

[0008] In a possible implementation manner, the phase composition of the MCrAlY bonding layer alloy includes 60-70% of β-NiAl phase and 15-25% of γ′-Ni3Al phase by volume fraction.

[0009] In a possible implementation manner, the phase composition of the MCrAlY bonding layer alloy further includes: an α-Cr phase and a Ni5Y intermetallic compound. By volume fraction, the α-Cr phase accounts for 10-15%, and the Ni5Y intermetallic compound accounts for 0.52-2%.

[0010] In one possible embodiment, Y and Ni are combined to form a Ni5Y intermetallic compound, Hf is located at the β-NiAl / γ'-Ni3Al two-phase interface, and Re is solid-dissolved in the α-Cr and γ'-Ni3Al phases.

[0011] In a possible embodiment, the average oxidation rate of the bonding layer alloy under isothermal oxidation at 1150° C. for 200 h is 0.05-0.1 g / (m 2 ·h); the thickness of the Al2O3 film formed by isothermal oxidation of the bonding layer alloy at 1150°C for 200h is not greater than 4.5-5.5μm.

[0012] In a possible implementation, the thermal expansion coefficient of the bonding layer alloy at 1150°C is not greater than 19.1×10 -6 / K; the thermal expansion coefficient of the bonding layer alloy at 1200°C is not greater than 19.5×10 -6 / K.

[0013] As a second aspect of the embodiment of the present disclosure, the embodiment of the present disclosure provides a method for preparing an alloy target ring, the alloy target ring includes the MCrAlY bonding layer alloy described in any of the above items, the method comprising: grinding and cleaning the metal raw material to obtain a clean raw material, the clean raw material includes Ni, Co, Cr, Re pure metals; loading the clean raw material into a crucible according to a proportion for vacuum induction melting, heating with a power of 5-15Kw, and a vacuum degree of 10 -2 -10 -1Pa, then adjust the power to 30-65Kw to melt the clean raw materials at 1500-1650℃, after the clean raw materials are melted, reduce the power to 25-30Kw and wait for 5-10min before adding active metals Al, Y and Hf, then increase the power to 45-50Kw for stirring and heating, and refine at 1600-1650℃ for 20-40min to form alloy liquid; after the refining is completed, reduce the power to 10-20Kw, wait until the alloy liquid temperature drops to 145 The invention relates to a method for preparing an alloy target ring by vacuum casting at a temperature of 0-1500°C; adopting an annular ceramic mold shell for precision casting, and the mold shell baking temperature is 800-1100°C; the vacuum degree of the vacuum casting treatment is 10-30Pa, the casting time of the vacuum casting treatment is 2-7s, and after the casting is completed, the alloy target ring blank is obtained by air cooling to room temperature in an atmospheric environment for 3-10min, and the shell is broken; the alloy target ring blank is machined to obtain the alloy target ring, and the impurity content of the alloy target material is less than 0.5wt%.

[0014] In a possible embodiment, the initial melting power during the vacuum induction melting process is 10-15Kw; the vacuum degree during the melting process is 5×10 -2 -5×10 -1 Pa; the melting power is 55-65Kw to melt the clean raw material at 1550-1600℃; the refining temperature is 1600-1620℃, and the refining time is 20-30min; the vacuum pouring treatment is carried out when the alloy liquid drops to 1450-1460℃; the mold shell baking temperature is 900-1000℃; the vacuum degree of the vacuum pouring treatment is 10-15Pa, the pouring time of the vacuum pouring treatment is 3-4s, and the waiting time after the pouring is 5-6min.

[0015] As a third aspect of an embodiment of the present disclosure, an embodiment of the present disclosure provides an alloy target ring, which is prepared by the method described above and can be used as a bonding layer for preparing a thermal barrier coating by vacuum arc ion plating deposition. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments according to the present disclosure and should not be regarded as limiting the scope of the present disclosure.

[0017] Figure 1 It is a schematic diagram of a method for preparing an alloy target ring according to one embodiment of the present disclosure;

[0018] Figure 2The SEM morphology images of the alloy phase composition of the bonding layer according to the embodiments and comparative examples of the present disclosure;

[0019] Figure 3 This is a comparison chart of the average weight gain per unit area of ​​the bonding layer alloy according to the embodiment of the present disclosure and the comparative example after isothermal oxidation at 1150° C. for 200 hours;

[0020] Figure 4 The SEM morphology of the oxide film surface of the bonding layer alloy according to the embodiment and the comparative example of the present disclosure after isothermal oxidation at 1150° C. for 200 hours;

[0021] Figure 5 The cross-sectional SEM morphology of the oxide film of the bonding coating according to the embodiment and comparative example of the present disclosure after isothermal oxidation at 1150° C. for 200 h. DETAILED DESCRIPTION

[0022] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present disclosure, and different embodiments may be combined arbitrarily without conflict. Therefore, the drawings and descriptions are considered to be illustrative in nature and not restrictive.

[0023] As a first aspect of the embodiment of the present disclosure, the embodiment of the present disclosure provides an MCrAlY bonding layer alloy, which includes, by weight percentage, Cr 13-18wt%, Co 10-15wt%, Al12-17wt%, Y 0.25-1.0wt%, Hf0.3-0.9wt%, Re 0.3-1.0wt%, and the rest is Ni. As a result, the bonding layer alloy has good oxidation resistance, and is not easy to peel off and crack when used as a coating, especially when used for annular targets of vacuum arc ion plating, it has good performance and is not easy to crack; and it can have good performance at 1150°C and higher temperatures, and has a high yield rate, and is suitable for industrial production.

[0024] For ease of understanding, the principle by which the MCrAlY bonding layer alloy according to the embodiment of the present application can achieve the above beneficial effects is described in detail below:

[0025] With the continuous improvement of the thrust-to-weight ratio of aircraft engines, the long-term use temperature of the bonding layer material of the thermal barrier coating is required to reach above 1150℃. However, the current use temperature of the MCrAlY bonding layer material generally does not exceed 1100℃. At 1150℃ and higher, the growth rate of its oxide film is fast, the anti-oxidation performance deteriorates, and the coating is prone to peeling. The main way to improve the oxidation resistance of MCrAlY is to regulate the alloying composition, phase structure, and adopt various forms of coating preparation methods. To this end, it is mostly solved from the aspects of preparing double-layer or even multi-layer MCrAlY coatings and gradient coatings. For example, in some methods, the NiCrAlYSi layer is first prepared on the nickel-based high-temperature alloy substrate by vacuum arc ion plating, and then aluminum is infiltrated by chemical vapor deposition to form an outer NiAl layer and an inner NiCrAlYSi bonding layer; in some methods, by adding alloying elements Fe, Hf and a high content of Ta to NiCoCrAlY, AlCoCrFeNiTaHfY high entropy alloy powder is prepared by vacuum melting + vacuum atomization, and then the bonding layer coating is prepared by supersonic plasma spray deposition.

[0026] The inventors found that excessive addition of alloying elements may lead to the formation of complex brittle phases in the alloy, reducing the mechanical properties of the coating and the base alloy, especially the annular target used in vacuum arc ion plating. Due to the large temperature difference between the inner and outer surfaces of the target due to its internal water cooling jacket, it is not possible to use high alloy and high activity element systems like supersonic plasma spraying, EB-PVD and other technologies, otherwise the target is prone to cracking during use. The method of using multi-layer coating or gradient coating is complicated to operate and has low production efficiency. In view of the technical advantages of preparing MCrAlY coating by vacuum arc ion plating, and taking the low cost and simple operation process of single-component MCrAlY coating as the starting point, the inventors in this application adjust the composition and phase composition of the bonding layer material, while taking into account high oxidation resistance and the coating is not easy to peel off, to avoid the problem of easy cracking of the annular target used in vacuum arc ion plating during use, and can have good performance at 1150°C and higher temperatures, and has a high yield rate, which is suitable for industrial production.

[0027] In a possible embodiment, by weight percentage, the Cr content in the bonding layer alloy may be 14wt%, 15-18wt%, 16wt%, 17wt%, etc.; the Co content in the bonding layer alloy may be 11-14wt%, 12wt%, 13wt%, etc.; the Al content in the bonding layer alloy may be 13-16wt%, 14wt%, 15wt%, etc.; the Y content in the bonding layer alloy may be 0.25-0.6wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.7wt%, 0.8wt%, etc.; the Hf content in the bonding layer alloy may be 0.3-0.8wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt%, etc.; the Re content in the bonding layer alloy may be 0.4-0.7wt%, 0.5wt%, 0.6wt%, 0.8wt%, 0.9wt%, etc. Therefore, when the content of each component in the bonding layer alloy is within the above range, it has good oxidation resistance, is not easy to peel off and crack when used as a coating, and can have good performance at 1150°C and higher temperatures, and has a high yield rate, and is suitable for industrial production.

[0028] In a possible embodiment, the phase composition of the bonding layer alloy may include 60-70% of β-NiAl phase and 15-25% of γ'-Ni3Al phase by volume fraction. Further, by volume fraction, it may include 10-15% of α-Cr phase and 0.52-2% of Ni5Y intermetallic compound; specifically, Y and Ni may combine to form Ni5Y intermetallic compound, Hf may be located at the β-NiAl / γ'-Ni3Al two-phase interface, and Re may be dissolved in α-Cr and γ'-Ni3Al phases. In a possible embodiment, by volume fraction, the phase composition of the bonding layer alloy may include 63-68% of β-NiAl phase and 18-21% of γ'-Ni3Al phase, and 12-15% of low expansion α-Cr phase. Thus, the bonding layer alloy having the above-mentioned phase composition can take into account high oxidation resistance and coating that is not easy to peel off, and can effectively solve the problem of easy cracking of the ring target used in vacuum arc ion plating during use.

[0029] The inventors found that the oxidation resistance of the MCrAlY bonding layer is largely affected by the Al content in the coating. A higher Al content is easy to form an Al-rich β-NiAl phase, which can continuously provide sufficient Al elements for TGO to form a dense Al2O3 layer during high-temperature oxidation, thereby improving oxidation resistance; but the Al content should not be too high, otherwise the brittleness of the MCrAlY coating itself will increase and the mechanical properties will deteriorate. The γ'-Ni3Al coating can reduce the chemical composition difference between the coating and the nickel-based high-temperature alloy substrate, thereby reducing the driving force for the mutual diffusion of the coating substrate. Hf and Y are active elements, and a small amount of addition can significantly improve the adhesion of the oxide film on the surface of the coating and reduce the growth rate of the oxide film. The addition of Re can not only reduce the rate of Al diffusion outward, but also promote the formation of a low-expansion α-Cr phase, and the α-Cr phase itself is conducive to reducing the thermal expansion coefficient of the coating, avoiding the problem of premature failure of the coating caused by the mismatch between the expansion properties of the coating and the substrate. However, the addition of Re will also induce the formation of brittle σ-Co (Cr) phase, especially when the Co content is high, the content of brittle σ-Co (Cr) phase is higher, which can easily lead to cracking problems during the smelting and forming of vacuum arc plating targets and arc plating, especially the annular targets. In addition, a high content of σ-Co (Cr) phase will also cause the adhesion of the coating oxide film to deteriorate, and it will peel off and fail prematurely, so the content of Re and Co should not be too high. Therefore, in this application, the inventors regulate the reasonable content of β-NiAl and γ'-Ni3Al phases in the bonding layer target by regulating the composition of the bonding layer material, while ensuring a certain low expansion α-Cr phase to avoid stress-induced coating failure. Thereby achieving both high oxidation resistance and the coating not being easy to peel off, and effectively solving the problem of easy cracking of the annular target used in vacuum arc ion plating during use.

[0030] Therefore, in the present application, (1) through reasonable composition design, the idea of ​​higher Al content and lower content of multi-active elements is adopted to adjust the main phase types of the bonding layer material to 60-70% β-NiAl phase and 15-25% γ'-Ni3Al phase, containing 10-15% low expansion α-Cr phase and a small amount of Ni5Y intermetallic compound, and the Al-rich β-NiAl phase continuously provides sufficient Al elements for oxidation to improve oxidation resistance; Y, Hf, and Re are used to improve the oxidation resistance of the bonding layer and the adhesion of the oxide layer, so that a single-layer MCrAlY coating can achieve a complete oxidation resistance level of 200h at 1150°C. (2) By reasonably regulating the MCrAlY component system, the excessively high Al, Co and Re contents leading to the appearance of a large number of brittle phases such as σ-Co (Cr) are avoided, and the problem of easy cracking caused by the large temperature difference between the inner and outer rings of the ring target caused by the internal water cooling jacket when the vacuum arc ion plating uses annular target materials to prepare coatings is solved. Combined with the starting point of preparing a single antioxidant coating, the present application has the characteristics of simple preparation process, high production efficiency, and is suitable for industrial production.

[0031] In a possible embodiment, the average oxidation rate of the bonding layer alloy under isothermal oxidation at 1150° C. for 200 h can be 0.05-0.1 g / (m 2 h), for example, 0.06 g / (m 2 ·h), can be 0.07g / (m 2 ·h), can be 0.08g / (m 2 h), etc. Therefore, the bonding layer alloy has good oxidation resistance at higher temperatures and good performance.

[0032] In a possible implementation, the thickness of the Al2O3 film formed by isothermal oxidation of the bonding layer alloy at 1150°C for 200 hours may be no greater than 4.5-5.5 μm, for example, no greater than 5 μm, no greater than 4 μm, etc. Thus, the bonding layer alloy has better oxidation resistance at higher temperatures and good performance.

[0033] In one possible embodiment, the thermal expansion coefficient of the bonding layer alloy at 1150°C may be no greater than 19.1×10 -6 / K, the thermal expansion coefficient of the bonding layer alloy at 1200°C may be no greater than 19.5×10 -6 / K. Therefore, the thermal expansion coefficient of the bonding layer alloy at 1150°C and 1200°C is lower than that of the commonly used MCrAlY alloy by 21.0×10 -6 / K and 21.3×10 -6 / K. The bonding layer alloy has good stability at higher temperatures and good performance. Therefore, in the present application, by reasonably increasing the Al content, regulating the content of the oxidation-resistant Al-rich β-NiAl phase and the γ'-Ni3Al phase with low diffusion with the matrix alloy, it is ensured that the phase composition contains the α-Cr phase, thereby ensuring that the high-temperature oxidation resistance is improved while obtaining a low thermal expansion coefficient.

[0034] As a second aspect of the embodiments of the present disclosure, the embodiments of the present disclosure provide a method for preparing an alloy target ring, which may include the MCrAlY bonding layer alloy described in any of the above items, thereby, the alloy target ring prepared by the method has all the characteristics and advantages of the MCrAlY bonding layer alloy described above, which will not be repeated again. According to some embodiments of the present application, reference Figure 1 , the method comprising:

[0035] S100: Grinding and cleaning of metal raw materials to obtain clean raw materials

[0036] In this step, the metal raw material is polished and cleaned to obtain a clean raw material, which may include pure metals such as Ni, Co, Cr, and Re.

[0037] S200: The clean raw materials are subjected to vacuum induction melting to form alloy liquid

[0038] In this step, the clean raw materials obtained in the previous step are subjected to vacuum induction melting to form alloy liquid. Specifically, the clean raw materials can be placed in an alumina or magnesium oxide crucible according to the ratio for vacuum induction melting. The heating can be powered by 5-15Kw power first, and the vacuum degree of the melting process can be 10 -2 -10 -1 Pa, then adjust the power to 30-65Kw to melt the clean raw material at 1500-1650℃, after the clean raw material is melted, reduce the power to 25-30Kw and wait for 5-10min before adding active metals Al, Y and Hf, then increase the power to 45-50Kw for stirring and heating, and refine at 1600-1650℃ for 20-40min to form alloy liquid. Furthermore, the initial melting power during vacuum induction melting can be 10-15Kw; the vacuum degree during the melting process can be 5×10 -2 -5×10 -1 Pa; the melting power can be 55-65Kw to melt the clean raw materials at 1550-1600℃; the refining temperature can be 1600-1620℃, and the refining time can be 20-30min.

[0039] S300: Vacuum casting the alloy liquid to obtain the alloy target ring blank

[0040] In this step, the alloy liquid obtained in the previous step is subjected to vacuum pouring treatment to obtain an alloy target ring blank. Specifically, after the refining in the previous step is completed, the power can be reduced to 10-20Kw, and vacuum pouring treatment can be performed when the temperature of the alloy liquid drops to 1450-1500°C; specifically, an annular ceramic mold shell can be used for precision casting, and the mold shell baking temperature can be 800-1100°C; the vacuum degree of vacuum pouring treatment can be 10-30Pa, and the pouring time of vacuum pouring treatment can be 2-7s. After the pouring is completed, it can be waited for 3-10min to break the air and air-cool to room temperature in the atmospheric environment, and the shell is broken to obtain the alloy target ring blank. Further, vacuum pouring treatment can be performed when the alloy liquid drops to 1450-1460°C; the mold shell baking temperature can be 900-1000°C; the vacuum degree of vacuum pouring treatment can be 10-15Pa, and the pouring time of vacuum pouring treatment can be 3-4s, and the waiting time after the pouring is completed can be 5-6min.

[0041] S400: Machining the alloy target ring blank to obtain the alloy target ring

[0042] In this step, the alloy target ring blank obtained in the previous step is machined to obtain an alloy target ring, and the impurity content of the alloy target material can be lower than 0.5wt%.

[0043] As the third aspect of the embodiment of the present disclosure, the embodiment of the present disclosure provides an alloy target ring, which is prepared by the method described above, and the alloy target ring can be used as a bonding layer for preparing a thermal barrier coating by vacuum arc ion plating deposition. Therefore, the alloy target ring has all the characteristics and advantages of the alloy target ring prepared by the method described above, which will not be repeated here. In general, the alloy target ring has good oxidation resistance, is not easy to peel off and crack during coating, especially when used for annular targets for vacuum arc ion plating, it has good performance and is not easy to crack; and can have good performance at 1150°C and higher temperatures, and has a high yield, which is suitable for industrial production. Specifically, the alloy target is suitable for preparing MCrAlY coatings from vacuum arc ion plating annular targets, and is used in MCrAlY bonding layer materials for turbine blades of aero-engines at a service temperature of 1150°C. Specifically, the base alloy of the coating prepared by vacuum arc ion plating can preferably be a single crystal high-temperature alloy.

[0044] Example 1

[0045] The composition of MCrAlY alloy is Co 13.5wt%, Cr 17.3wt%, Al 15.8wt%, Y0.41wt%, Hf0.35wt%, Re 0.7wt%, and Ni balance. The preparation process of MCrAlY bonding layer alloy target is as follows: melting in medium frequency vacuum induction furnace, the raw materials are polished and cleaned before entering the furnace; Ni block, Co block, Cr granules, Re granules are loaded into alumina crucible according to the proportion, and the power is supplied and heated at 10Kw. The vacuum degree of the melting process is controlled to 8×10 -2 Pa, then adjust the power to 60Kw to melt the charge at 1590℃, after the charge is melted, reduce the power to 30Kw and wait for 10min before adding active metals Al, Y and Hf, then increase the power to 50Kw for stirring and heating, and refine at 1630℃ for 30min. After the refining is completed, reduce the power to 10Kw, and vacuum pouring is carried out when the temperature of the alloy liquid drops to 1480℃. The membrane shell baking temperature is 950℃, the pouring vacuum degree is controlled to 12Pa, the pouring time is controlled to 4s, and after the pouring is completed, wait for 7min to break the air and cool to room temperature in the atmospheric environment, break the shell to obtain the alloy target ring blank, and then machine the final finished alloy target ring with an impurity content of less than 0.35wt%.

[0046] Comparative Example 1

[0047] A commercial NiCoCrAlYHf alloy was used as a comparative example.

[0048] Performance Testing

[0049] (1) SEM test

[0050] The SEM morphology test was performed on the alloy phase composition of the bonding layer of Example 1 and Comparative Example 1, and the obtained SEM morphology is shown in Figure 2 ,in Figure 2 (a) is the SEM image of the bonding layer alloy in Example 1, Figure 2 (b) is a SEM image of the bonding layer alloy in Comparative Example 1. Figure 2 As shown in (a), the phase composition of the bonding layer alloy prepared in Example 1 is 68.3% of β-NiAl phase, 18.6% of γ'-Ni3Al phase, and 12.1% of α-Cr phase. Figure 2 (b) shows that the phase composition of NiCoCrAlYHf in Comparative Example 1 is 55.7% of β-NiAl phase. In comparison, the β-NiAl phase ratio of the bonding layer provided by Example 1 is higher than that of NiCoCrAlYHf. The increase in the content of Al-rich β-NiAl phase means that the oxidation resistance of the alloy material will be improved.

[0051] (2) Isothermal oxidation performance test

[0052] According to the requirements of HB5258-2000 "Test Method for Determination of Oxidation Resistance of Steel and High-temperature Alloys", the bonding layer alloy target samples in Example 1 and Comparative Example 1 were subjected to an isothermal oxidation performance test at 1150°C × 200h, and the samples after the test were analyzed and studied, the oxidation rate was recorded, and its oxidation resistance was evaluated. Comparison of the average unit area oxidation weight gain of the two alloy targets in Example and Comparative Example 1 after isothermal oxidation at 1150°C for 200h Figure 3 The average unit area oxidation increment of the bonding layer alloy provided in Example 1 after isothermal oxidation at 1150°C for 200 hours is 18.42 g / m 2 The average oxidation rate is 0.092g / (m 2 ·h), less than 0.1g / (m 2 h), reaching the complete oxidation resistance level. The average unit area oxidation increment of NiCoCrAlYHf in Comparative Example 1 is 27.26 g / m 2 The average oxidation rate is 0.136g / (m 2 ·h), the oxidation weight gain and oxidation rate are significantly higher than those in Example 1.

[0053] Further, Figure 4The surface morphology of the bonding layer alloy provided in Example 1 and Comparative Example 1 after isothermal oxidation at 1150° C. for 200 h under the scanning electron microscope backscattering mode is shown in FIG. Figure 4 (a) is the surface morphology of the bonding layer alloy in Example 1, Figure 4 (b) is the surface morphology of the bonding layer alloy in Comparative Example 1. Figure 4 (a) and Figure 4 (b) It was found that the bonding layer alloy provided in Example 1 can form a continuous and dense α-Al2O3 film, with only a small amount of oxide film peeling off in local areas, and the peeling area is still the oxide film; while the oxide film of the comparative example NiCoCrAlYHf peels off obviously, with a larger area, and the bonding layer matrix has been exposed at the peeling area; obviously, the high-temperature oxidation resistance of the bonding layer alloy provided in Example 1 is better than that of the comparative example NiCoCrAlYHf.

[0054] Further, using the alloys in Example 1 and Comparative Example 1, a vacuum degree of <1×10 -2 The MCrAlY bonding layer and the commercial NiCoCrAlYHf coating were prepared by vacuum arc ion plating process with a temperature of 1000 Pa, a voltage of 650 V, a current of 20 A, and a deposition time of 120 min. After the coating was isothermally oxidized at 1150°C for 200 h, the oxide film of the coating prepared by the MCrAlY target material provided in Example 1 was a continuous and dense Al2O3 (such as Figure 5 (a)), while the oxide film of the coating prepared by the commercial NiCoCrAlYHf target is a double-layer oxide structure of Ni, Co, Al mixed oxide + Al2O3 (as shown in Figure 5 (b) shows that the coating prepared by the bonding layer target material provided in the embodiment has better oxidation resistance than the commercial NiCoCrAlYHf coating after isothermal oxidation at 1150°C for 200h.

[0055] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present disclosure, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0056] In the present disclosure, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0057] In the present disclosure, unless otherwise clearly specified and limited, the first feature "above" or "below" the second feature may include the first and second features being in direct contact, or the first and second features being not in direct contact but in contact through another feature between them. Moreover, the first feature "above", "above" and "above" the second feature include the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature "below", "below" and "below" the second feature include the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is lower in level than the second feature. The above disclosure provides many different embodiments or examples for implementing different structures of the present disclosure. In order to simplify the present disclosure, the components and settings of specific examples are described above. Of course, they are merely examples and are not intended to limit the present disclosure. In addition, the present disclosure may repeat reference numbers and / or reference letters in different examples, and such repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed.

[0058] The above are only specific embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any technician familiar with the technical field can easily think of various changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A MCrAlY bonding layer alloy, characterized in that: In terms of weight percentage, the MCrAlY bonding layer alloy comprises: 13-18wt% Cr, 10-15wt% Co, 12-17wt% Al, 0.25-1.0wt% Y, 0.3-0.9wt% Hf, 0.3-1.0wt% Re, and the remainder is Ni.

2. The MCrAlY bonding layer alloy according to claim 1, characterized in that In terms of weight percentage, the MCrAlY bonding layer alloy comprises: 15-18wt% Cr, 13-15wt% Co, 13-16wt% Al, 0.25-0.6wt% Y, 0.3-0.8wt% Hf, 0.4-0.7wt% Re, and the remainder Ni.

3. The MCrAlY bonding layer alloy according to claim 1, characterized in that: The phase composition of the MCrAlY bonding layer alloy includes 60-70% of β-NiAl phase and 15-25% of γ′-Ni3Al phase by volume fraction.

4. The MCrAlY bonding layer alloy according to claim 3, characterized in that The phase composition of the MCrAlY bonding layer alloy further includes: α-Cr phase and Ni5Y intermetallic compound, In terms of volume fraction, the α-Cr phase accounts for 10-15%, and the Ni5Y intermetallic compound accounts for 0.52-2%.

5. The MCrAlY bonding layer alloy according to claim 4, characterized in that Y and Ni combine to form Ni5Y intermetallic compound, Hf is located at the interface of β-NiAl / γ'-Ni3Al phases, and Re is dissolved in α-Cr and γ'-Ni3Al phases.

6. The MCrAlY bonding layer alloy according to claim 1, characterized in that: In terms of weight percentage, the MCrAlY bonding layer alloy comprises: 15-18wt% Cr, 13-15wt% Co, 12-16wt% Al, 0.25-0.5wt% Y, 0.3-0.5wt% Hf, 0.5-1.0wt% Re, and the remainder Ni.

7. The MCrAlY bonding layer alloy according to claim 1, characterized in that: The average oxidation rate of the MCrAlY bonding layer alloy under isothermal oxidation at 1150°C for 200 hours is 0.05-0.1 g / (m 2 h); and / or, The thickness of the Al2O3 film formed by isothermal oxidation of the MCrAlY bonding layer alloy at 1150°C for 200h is not greater than 4.5-5.5 μm; and / or, The thermal expansion coefficient of the MCrAlY bonding layer alloy at 1150°C is not greater than 19.1×10 -6 / K; and / or, The thermal expansion coefficient of the MCrAlY bonding layer alloy at 1200°C is not greater than 19.5×10 -6 / K.

8. A method for preparing an alloy target ring, characterized in that: The alloy target ring comprises the MCrAlY bonding layer alloy according to any one of claims 1 to 7, and the method comprises: Grinding and cleaning the metal raw materials to obtain clean raw materials, wherein the clean raw materials include pure metals such as Ni, Co, Cr, and Re; The clean raw materials are placed in a crucible according to the ratio and subjected to vacuum induction melting treatment. The heating is powered by 5-15Kw power and the vacuum degree during the melting process is 10 -2 -10 -1 Pa, then adjust the power to 30-65Kw to melt the clean raw materials at 1500-1650°C, after the clean raw materials are melted, reduce the power to 25-30Kw and wait for 5-10min before adding active metals Al, Y and Hf, then increase the power to 45-50Kw to stir and heat, and refine at 1600-1650°C for 20-40min to form alloy liquid; After the refining is completed, the power is reduced to 10-20Kw, and vacuum casting is performed when the alloy liquid temperature drops to 1450-1500°C; an annular ceramic mold is used for precision casting, and the mold baking temperature is 800-1100°C; the vacuum degree of the vacuum casting is 10-30Pa, and the casting time of the vacuum casting is 2-7s. After the casting is completed, wait for 3-10min to break the air and air cool to room temperature in the atmospheric environment, and break the shell to obtain the alloy target ring blank; The alloy target ring blank is machined to obtain the alloy target ring, and the impurity content of the alloy target material is less than 0.5wt%.

9. The method according to claim 8, characterized in that The initial melting power during the vacuum induction melting process is 10-15Kw; the vacuum degree during the melting process is 5×10 -2 -5×10 -1 Pa; the melting power is 55-65Kw to melt the clean raw material at 1550-1600℃; the refining temperature is 1600-1620℃, and the refining time is 20-30min; the vacuum pouring treatment is carried out when the alloy liquid drops to 1450-1460℃; the mold shell baking temperature is 900-1000℃; the vacuum degree of the vacuum pouring treatment is 10-15Pa, the pouring time of the vacuum pouring treatment is 3-4s, and the waiting time after the pouring is 5-6min.

10. An alloy target ring, characterized in that: The alloy target ring is prepared by the method described in claim 8 or 9, and the alloy target ring is used as a bonding layer for preparing a thermal barrier coating by vacuum arc ion plating deposition.

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