A compressor blade and a method for manufacturing the same, and a compressor

Abstract

The application relates to a compressor blade and a preparation method thereof and a compressor; the preparation method comprises the following steps: subjecting a GH4068 alloy blank with an average grain size of 1-15 mu m to a structure homogenization treatment at 980-1120 DEG C; extruding a part of the blank after the structure homogenization treatment to obtain a blank with an extrusion deformation part; the extrusion deformation amount is 40-50%; the non-deformed part is die forged into a tenon; the extrusion deformation part is subjected to pre-die forging and final forging treatment to form a blade body with a set thickness, thereby obtaining a compressor blade blank with the blade body and the tenon; and the compressor blade blank is sequentially subjected to heat treatment and finishing, thereby obtaining the compressor blade; in the above steps: the blank needs to be subjected to a 980-1120 DEG C re-melting heat preservation treatment between each deformation pass. The application has simple blade preparation tool requirements, can prepare a GH4068 alloy blade resistant to 750 DEG C on an existing GH4169 alloy blade production line resistant to 650 DEG C, significantly reduces production cost, and is suitable for batch production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aero-engine blade, and particularly relates to a compressor blade and a preparation method thereof and a compressor. BACKGROUND

[0002] With the progress of science and technology, the thrust-to-weight ratio of an aero-engine is gradually increased, which leads to a higher and higher outlet temperature of the engine, and accordingly, the material of the high-pressure compressor blade, a key rotor component, needs to have a higher and higher temperature resistance.

[0003] The material of a conventional high-pressure compressor blade is mainly GH4169 (In718) and GH4169D (In718Plus) alloy, and the temperature resistance of these alloys is below 700 DEG C. In order to improve the maneuverability of an aircraft, GH4065 (René88DT), GH4720Li (U720Li) and GH4068 alloys are planned to be applied in the future, and the temperature resistance of the GH4068 alloy can reach 750 DEG C. However, with the increase of the temperature resistance, the preparation difficulty of the blade is significantly increased.

[0004] The blade of the compressor has a small thickness, a complex machining process, a large number of forming passes and a long time consumption, and the preparation difficulty is great. The GH4068 alloy has a high degree of alloying, and the content of the gamma prime phase in the alloy is more than 45%, so the deformation resistance is great and the hot plasticity is low, and the GH4068 alloy cannot be prepared by using a traditional method. Therefore, the prior art has not been able to prepare the compressor blade made of the GH4068 alloy.

[0005] In summary, how to prepare the GH4068 alloy high-pressure compressor blade with a temperature resistance of 750 DEG C is a problem in the prior art. SUMMARY

[0006] Therefore, the present application provides a compressor blade and a preparation method thereof and a compressor, and the main purpose is to prepare the GH4068 alloy high-pressure compressor blade with a temperature resistance of 750 DEG C.

[0007] To achieve the above purpose, the present application mainly provides the following technical scheme:

[0008] In one aspect, the embodiment of the present application provides a preparation method of a compressor blade, wherein the material of the compressor blade is GH4068 alloy; and the preparation method comprises the following steps:

[0009] Step 1): a GH4068 alloy blank with an average grain size of 1-15 microns is kept at a temperature of 980-1120 DEG C for a set time to perform a microstructure homogenization treatment, and a blank after the microstructure homogenization treatment is obtained;

[0010] Step 2): after the end of the heat preservation, a part of the blank after the homogenization treatment is directly extruded to obtain a blank with an extruded part; wherein the extrusion deformation is 40-50%;

[0011] Step 3): the non-deformed part of the blank with the extruded part is die forged into a tenon;

[0012] Step 4): the extruded part is pre-die forged and finish forged to form a blade with a set thickness, thereby obtaining a compressor blade blank with a blade and a tenon;

[0013] Step 5): the compressor blade blank is sequentially heat treated and finished machined to obtain a compressor blade;

[0014] In any one of steps 2) to 4), the blank needs to be re-melted and heat treated between each deformation, wherein the re-melting and heat treatment temperature is 980-1120°C. It should be noted that "each deformation" refers to one deformation of extrusion, one deformation of die forging, one deformation of pre-die forging, and one deformation of finish forging. The blank needs to be re-melted and heat treated before each deformation.

[0015] Preferably, in step 1), the set time is 1-4h; and / or the grain size of the blank after the homogenization treatment is ≤15μm, and the grain size difference is ≤2 levels.

[0016] Preferably, the diameter of the non-deformed part of the blank with the extruded part is 20-40mm; and / or the tenon is a rhombus section.

[0017] Preferably, in step 4), after the end of the heat preservation in step 1), the blank after the homogenization treatment is transferred from the heat preservation furnace to the extrusion die within 5s for extrusion.

[0018] Preferably, the extruded part with a diameter of 8-30mm is pre-die forged to form a blade with a thickness of 4-7mm, and then further finish forged to make the thickness of the blade 1-3mm; and / or after the finish forging, the compressor blade blank with the blade and the tenon is cooled to room temperature for edge cutting.

[0019] Preferably, in any one of the steps 2) to 4), the holding treatment is 1 to 4 hours; and / or before the holding treatment, an antioxidant is sprayed on the surface of the blank to lubricate the subsequent deformation; preferably, the antioxidant is a glass antioxidant; preferably, the thickness of the sprayed antioxidant is 0.3 to 0.8 mm; and / or after each deformation, the surface of the blank is checked for cracks; if cracks are found, polishing is performed to eliminate the cracks; and / or the preheating temperature of the mold is 300 to 500°C, and before the blank is transferred to the mold, graphite lubricant is sprayed in the mold; and / or after the holding treatment, the time interval for transferring the blank from the holding furnace to the mold is controlled to be within 5 seconds; and / or the microcrystalline grain size of the blank after each deformation is within 10 μm; and / or the strain rate of each deformation is ≥ 0.1 s -1 .

[0020] Preferably, the heat treatment step includes: heating the compressor blade blank to 1080 to 1130°C, holding for 2 to 6 hours, and then quenching; then heating to 600 to 700°C, holding for 16 to 30 hours, and then cooling; and finally heating to 750 to 800°C, holding for 10 to 20 hours, and then cooling; preferably, the quenching is oil quenching; and preferably, the cooling is air cooling.

[0021] Preferably, the microcrystalline grain size of the compressor blade blank after heat treatment is within 90 μm. It should be noted that although the microcrystalline grain size of the blank after each deformation is within 10 μm, the final heat treatment will cause the grain size to grow. During deformation, fine grains have good hot plasticity and low deformation resistance, which makes it easy to shape the blade.

[0022] In another aspect, the embodiment of the present application provides a compressor blade, wherein the material of the compressor blade is GH4068 alloy; preferably, the microstructure grain size of the compressor blade is within 90 μm; preferably, the GH4068 alloy comprises the following chemical elements in percentage by weight: Co 20-28 wt%, Ta 0-4 wt%, Cr 10-17 wt%, Ti 3-7 wt%, Al 0.2-5 wt%, W 0.1-3 wt%, Mo 0.1-5 wt%, Nb 0-3 wt%, Mn 0-0.5 wt%, V 0-0.4 wt%, C 0.005-0.1 wt%, Zr 0.01-0.1 wt%, B 0.001-0.1 wt%, and the balance of Ni and inevitable impurities; preferably, the compressor blade is prepared by the preparation method of the compressor blade according to any one of the above. In addition, the microstructure of the compressor blade is uniform, and the grain size difference caused by the deformation amount of each part is avoided. At the same time, since the grain size of the blade blank is small, the grain size can be adjusted according to the working condition requirement of the blade.

[0023] In another aspect, the embodiment of the present application provides a compressor, characterized in that the compressor comprises the compressor blade according to the above.

[0024] Compared with the prior art, the compressor blade and the preparation method thereof and the compressor provided by the present application at least have the following beneficial effects:

[0025] The preparation method of the compressor blade provided by the present application is mainly to prepare a high-pressure compressor blade from a GH4068 alloy blank. Since the GH4068 alloy has a high degree of alloying, the content of γ' phase contained in the alloy is more than 45%, the deformation resistance is large, and the thermal plasticity is low, and the traditional method cannot be used for preparation. The present application firstly maintains the uniform microstructure before deformation by heat treatment, then controls the temperature to make the GH4068 alloy have superplasticity, and controls the deformation amount and the forming step (for example, the forming of the extrusion rod and the tenon is divided into two steps), so that the high-pressure compressor blade made of the GH4068 alloy material is successfully prepared.

[0026] Specifically, the grain size of the blank for the compressor blade is ≤15 μm, and the fine-grained GH4068 alloy has superplasticity at 950-1130 °C, and the tensile plasticity elongation is above 300%. The preparation method of the present application first carries out the holding treatment of the blank at 980-1120 °C for a set time, so that the structure of the blank is uniformly distributed, and the grain size difference is not more than 2 levels. In order to improve the utilization rate of the material, reduce the flash area, and reduce the equipment requirement tonnage, the blank is processed into an extruded rod, and the deformation amount of the extruded rod is set to 40-50% by comprehensively considering the plasticity of the material and the size and shape of the blade body part, so as to obtain an extruded rod (i.e. an extruded deformation part) with a diameter of Φ8-30 mm. The undeformed part (Φ20-40 mm) of the extruded rod is die forged from a circular cross section into a rhombic cross section tenon for subsequent tenon tooth processing. Then the extruded deformation part (Φ8-30 mm) is pre-die forged into a blade body, and the thickness of the blade body after forming is 4-7 mm. The blade has flash after pre-forming, and the pre-forming process reduces the deformation amount of the blade body during the forming process, prevents the blade body from cracking, improves the service life of the forming die, and reduces the dependence of the forming process on the equipment tonnage. Finally, the pre-formed blade is further finish forged into a blank with a blade body thickness of 1-3 mm. Due to the small deformation amount and good alloy fluidity, the forming precision is high, and the subsequent machining amount is small. The time for each step of thermal deformation from the heat treatment furnace to the die is controlled within 5 s. At the same time, after each forming, the surface of the blank needs to be checked for cracks. If there are cracks, the cracks need to be polished to prevent the cracks from expanding during further deformation and causing the blade specimen to break. The blade is edge trimmed at room temperature to remove the excess flash. The blade blank is heat treated to adjust the grain size according to the performance requirements, and a large amount of fine dispersed γ' phase strengthening alloy is contained in the crystal grains to improve the temperature resistance of the blade. Finally, mechanical processing is carried out to remove the excess amount of the blade body and tenon part. Since the present application is near-net forming, the material amount is small, the processing difficulty is low, the material utilization rate is high, and the cost of the blade is reduced.

[0027] In summary, the present application provides a preparation method of a high-pressure compressor blade of GH4068 alloy, which can effectively reduce the alloy deformation resistance, improve the alloy yield, and improve the uniformity of the alloy structure and performance, thereby providing a guarantee for the stable preparation of high-temperature-resistant compressor blades with a temperature resistance of 750 °C. The present application has simple requirements for blade preparation tooling, and can be used to prepare GH4068 alloy blades with a temperature resistance of 750 °C on the existing GH4169 alloy blade production line with a temperature resistance of 650 °C, thereby significantly reducing the production cost and being suitable for batch production.

[0028] The above description is only a summary of the technical solutions of the present application. In order to more clearly understand the technical means of the present application and to implement the content of the description, the following will describe the preferred embodiments of the present application in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 A photograph of the compressor blade prepared for Example 1.

[0030] Figure 2 A photograph of the initial microstructure of the GH4068 alloy.

[0031] Figure 3 A photograph of the microstructure of the compressor blade prepared for Example 1.

[0032] Figure 4 A photograph of the billet after extrusion rod processing in the preparation step of Example 1.

[0033] Figure 5 A photograph of the billet after tenon forming in the preparation step of Example 1.

[0034] Figure 6 A photograph of the billet after pre-die forging in the preparation step of Example 1.

[0035] Figure 7 A photograph of the microstructure of the compressor blade prepared for Comparative Example 1. DETAILED DESCRIPTION

[0036] To further clarify the technical means and effects taken by the present application to achieve the intended purpose, the following describes the specific embodiments, structures, features, and effects of the present application in detail with reference to the accompanying drawings and preferred embodiments. In the following description, different "an embodiment" or "embodiments" do not necessarily refer to the same embodiment. In addition, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0037] The present application utilizes the fine-grain superplasticity method of difficult-to-deform high-temperature alloy. The fine-grain GH4068 alloy is first treated by heat treatment to maintain uniform deformation microstructure before deformation, and then extruded by high strain rate superplasticity to form a billet, form a tenon, pre-die forging, and terminal forming, so that the alloy has excellent thermal plasticity, extremely low deformation resistance, and obtains a uniform and fine deformed microstructure. Finally, edge cutting, performance control treatment, machining, and inspection are performed. Regarding the "high strain rate" described above, it should be noted that: generally, the strain rate of superplasticity is 0.001 s -1 below, while the strain rate of the present application is ≥0.1 s -1 Therefore, it is called high strain rate superplasticity.

[0038] The main scheme of the present application is as follows:

[0039] The present application provides a preparation method of a compressor blade (high-pressure high-pressure compressor blade), wherein the material of the compressor blade is GH4068 alloy; and the preparation method comprises the following steps:

[0040] Step 1): subjecting a GH4068 alloy blank with an average grain size of 1-15 μm to a microstructure homogenization treatment to obtain a microstructure homogenization treated blank; wherein the microstructure homogenization treatment is performed at a temperature of 980-1120 °C for a time of 1-4 h.

[0041] In this step, the grain size of the microstructure homogenization treated blank is ≤ 15 μm and the grain size difference is ≤ 2 grades.

[0042] The GH4068 alloy comprises the following chemical elements in weight percent: Co 20-28 wt%, Ta 0-4 wt%, Cr 10-17 wt%, Ti 3-7 wt%, Al 0.2-5 wt%, W 0.1-3 wt%, Mo 0.1-5 wt%, Nb 0-3 wt%, Mn 0-0.5 wt%, V 0-0.4 wt%, C 0.005-0.1 wt%, Zr 0.01-0.1 wt%, B 0.001-0.1 wt%, and the balance being Ni and unavoidable impurities.

[0043] Step 2): subjecting a part of the microstructure homogenization treated blank to an extrusion deformation (extrusion rod processing) to obtain a blank with an extrusion deformation part; wherein the extrusion deformation amount is 40-50%.

[0044] Step 3): die forging the non-deformed part (Φ20-40 mm) on the blank with the extrusion deformation part into a tenon (rhombus cross section).

[0045] Step 4): subjecting the extrusion deformation part to pre-die forging and finish forging treatment to form a blade with a set thickness to obtain a compressor blade blank with a blade and a tenon.

[0046] In this step: the extrusion deformation part (Φ8-30 mm) is pre-forged into a blade with a thickness of 4-7 mm, and the blade is finish forged into a thickness of 1-3 mm; the finish forged blade is cooled to room temperature, and then edge cutting is performed.

[0047] Step 5): sequentially subjecting the compressor blade blank to heat treatment and finishing to obtain a compressor blade.

[0048] In this step: the compressor blade blank is heated to 1080-1130 °C, held for 2-6 h, and then subjected to quenching treatment; then heated to 600-700 °C, held for 16-30 h, and then subjected to cooling treatment; finally heated to 750-800 °C, held for 10-20 h, and then subjected to cooling treatment; preferably, the quenching treatment is oil quenching; preferably, the cooling treatment is air cooling.

[0049] In any one of the steps 2) to 4), the blank is subjected to a re-melting and holding treatment between each deformation pass, wherein the re-melting and holding treatment is performed at a temperature of 980-1120°C.

[0050] Further, the following is explained in relation to the above scheme:

[0051] The blank for manufacturing the compressor blade is an open-die material with a grain size of ≤15μm. The GH4068 alloy with such fine grain structure has superplasticity at 950-1130°C, and the tensile plasticity elongation is above 300%. The manufacturing method of the present application first subjects the blank to a holding treatment at 980-1120°C for 1-4h, so that the structure of the blank is uniformly distributed, and the grain size difference is not more than 2 levels.

[0052] In order to improve the material utilization, reduce the flash area, and reduce the equipment requirement tonnage, the blank is subjected to an extrusion process. The plasticity of the material and the size and shape of the blade part are comprehensively considered, and the deformation amount of the extrusion is set to 40-50%, so as to obtain an extruded rod (i.e., an extrusion deformation part) with a diameter of Φ8-30mm. The non-deformed part (Φ20-40mm) of the extrusion rod is die forged from a circular cross section into a rhombic cross section tenon for subsequent tenon tooth processing. Then, the extrusion deformation part (Φ8-30mm) is subjected to one-step pre-die forging of the blade part, and the thickness of the blade part after forming is 4-7mm. The blade has flash after pre-forming. The pre-forming process reduces the deformation amount in the blade forming process, prevents cracking of the blade part, improves the service life of the forming die, and reduces the dependence of the forming process on the equipment tonnage. Finally, the pre-formed blade is further finish forged into a blank with a blade thickness of 1-3mm. Due to the small deformation amount and good alloy fluidity, the forming precision is high, and the subsequent machining amount is small. The time for each step of thermal deformation from the heat treatment furnace to the die is controlled to be within 5s. At the same time, after each forming, it is necessary to check whether the surface of the blank has cracks. If there are cracks, the cracks need to be polished to prevent the cracks from expanding in the further deformation process, resulting in rupture of the blade test piece. The blade is subjected to edge trimming at room temperature to remove the excess flash, as shown in FIG. 2. Figure 1 The blade blank is subjected to a solution and aging treatment, the grain size is adjusted according to the performance requirements, and a large number of fine dispersed γ' phase strengthening alloys are contained in the crystal grains, so as to improve the temperature resistance of the blade. Finally, the blade is subjected to mechanical processing to remove the excess amount of the blade part and the tenon. Since the present application is near-net forming, the material amount is small, the processing difficulty is low, the material utilization is high, and the cost of the blade is reduced.

[0053] The prior art generally uses GH4169 alloy to prepare high-pressure compressor blades, the temperature resistance of the alloy differs from that of GH4068 alloy by about 100 DEG C, and the processability of the alloy also has obvious difference. The GH4169 alloy has excellent hot plasticity and can have superplasticity below 1000 DEG C, the plastic elongation can be above 1000%, the alloying degree is low, the deformation resistance is small, and the blade body can be formed in one heating cycle to form the blade with a thickness of 2-3 mm. However, the GH4068 alloy contains more than 45% of γ' phase, the alloying degree is high, and the GH4068 alloy blade cannot be directly formed by using the forming process of the conventional GH4169 alloy high-pressure compressor blade. The application forms the high-pressure compressor blade with a temperature resistance of 750 DEG C by using the superplasticity of the GH4068 alloy, the blade body has small thickness, the material utilization rate is high, the forming rate is high, and the application is beneficial to improving the thrust-to-weight ratio of the aero-engine and the maneuverability of the aircraft.

[0054] The application is further described below by specific examples.

[0055] In the embodiment of the application, the GH4068 alloy blank with an average grain size of 1-15 μm is treated at a temperature of 980-1120 DEG C for 1-4 h; then the blank is transferred into an extrusion die within 5 s, and the blank is extruded and deformed by 40-50%; the deformed blank is treated at 980-1120 DEG C for 1-4 h, and then the blank is transferred into a tenon forming die within 5 s, and the non-deformed part (Φ20-40 mm) of the extrusion rod is die forged into a rhombic cross-section tenon; the blank is treated at 980-1120 DEG C for 1-4 h, and then the blank is transferred into a blade pre-forging forming die within 5 s, and the small-diameter part (Φ8-30 mm) of the extrusion rod is pre-die forged into a blade body with a thickness of 4-7 mm; the blank is treated at 980-1120 DEG C for 1-4 h, and then the blank is transferred into a blade final forging forming die within 5 s, and the blade body is finally forged into a thickness of 1-3 mm; the finally forged blade is cooled to room temperature, and then the blade is trimmed; the trimmed blade blank is heated to 1080-1130 DEG C and kept for 2-6 h, and then the blade is oil quenched; then the blade is heated to 600-700 DEG C and kept for 16-30 h, and then the blade is air cooled; finally, the blade blank is mechanically processed to obtain a blade product. The microstructure of the blade before and after forming is observed by using a Leica DM4M metallographic microscope. Figure 1

[0056] Example 1

[0057] The application discloses a preparation method of a compressor blade.

[0058] ​Step 1): The GH4068 alloy billet with average grain size of 5 μm was subjected to heat treatment at 980 °C for 4 h to obtain the homogenized billet.

[0059] Step 2): After the heat treatment in Step 1), the homogenized billet was transferred into an extrusion die (preheating temperature of the die was 300-500 °C) within 5 s, and a portion (40 mm in diameter) of the homogenized billet was subjected to extrusion deformation with a deformation of 43.75%, and was extruded into an extruded portion 3 with a diameter of 30 mm, as shown in Figure 4

[0060] Step 3): The extruded billet was subjected to heat treatment at 980 °C for 4 h, and then was transferred into a tenon forming die (preheating temperature of the die was 300-500 °C) within 5 s, and the non-deformed portion 4 (40 mm in diameter) of the extruded billet was die forged into a rhombic section to obtain a tenon 5, as shown in Figure 4 Figure 5

[0061] Step 4): The billet was subjected to heat treatment at 980 °C for 4 h, and then was transferred into a blade pre-forging die (preheating temperature of the die was 300-500 °C) within 5 s, and the extruded portion (30 mm in diameter) was subjected to pre-forging to obtain a blade 6 with a thickness of 7 mm, as shown in Figure 6 The billet was subjected to heat treatment at 980 °C for 4 h, and then was transferred into a blade final forging die (preheating temperature of the die was 300-500 °C) within 5 s, and the blade was subjected to final forging to obtain a blade with a thickness of 3 mm, to obtain a compressor blade billet with a blade and a tenon. The compressor blade billet was cooled to room temperature, and then was subjected to edge cutting, and the edge-cut blade billet is shown in Figure 1

[0062] In addition, the strain rate in the above steps (extrusion deformation, die forging, pre-forging, final forging) was ≥0.1 s -1 .

[0063] Step 5): The compressor blade billet was heated to 1080 °C, and was subjected to oil quenching after being kept for 6 h, and then was heated to 600 °C, and was subjected to air cooling after being kept for 30 h, and finally was heated to 800 °C, and was subjected to air cooling after being kept for 10 h, to obtain a heat-treated compressor blade billet.

[0064] Step 6): Finishing: the heat-treated compressor blade billet was subjected to mechanical processing to obtain a finished compressor blade.

[0065] The initial microstructure of the GH4068 alloy billet in this example is shown in Figure 2 ​​​​The average grain size is about 5 μm as shown. Figure 3 The average grain size is about 8 μm as shown.

[0066] Example 2

[0067] The present application relates to a method for manufacturing a compressor blade, comprising the following steps:

[0068] Step 1): The GH4068 alloy blank with an average grain size of 5 μm is subjected to heat treatment at a temperature of 1000 °C for 2 h to obtain a blank after homogenization of the structure.

[0069] Step 2): After the heat treatment of step 1), the blank is transferred to an extrusion die (preheating temperature of the die: 300-500 °C) within 5 s, and a part of the blank after homogenization of the structure (diameter: 30 mm) is subjected to extrusion deformation with a deformation of 46% to obtain an extrusion-deformed part with a diameter of 22 mm.

[0070] Step 3): The blank after extrusion deformation is subjected to heat treatment at 1000 °C for 2 h, and then transferred to a tenon forming die (preheating temperature of the die: 300-500 °C) within 5 s to form a tenon. The non-deformed part of the extrusion (diameter: 30 mm) is die forged into a rhombic cross section.

[0071] Step 4): The blank is subjected to heat treatment at 1000 °C for 2 h, and then transferred to a blade pre-forging forming die (preheating temperature of the die: 300-500 °C) within 5 s to pre-forging form a blade body from the extrusion-deformed part (Φ22 mm), and the thickness of the blade body after pre-forging is 5 mm. The blank is subjected to heat treatment at 1000 °C for 2 h, and then transferred to a blade final forging forming die (preheating temperature of the die: 300-500 °C) within 5 s to final forging form a blade body with a thickness of 2 mm to obtain a compressor blade blank comprising a blade body and a tenon. The compressor blade blank is cooled to room temperature, and then subjected to edge cutting.

[0072] In addition, the strain rate in the above steps (extrusion deformation, die forging, pre-forging, final forging) is ≥0.1 s -1 .

[0073] Step 5): The compressor blade blank is heated to 1100 °C, and then subjected to oil quenching after heat preservation for 4 h. Then the blank is heated to 650 °C, and then subjected to air cooling after heat preservation for 24 h. Finally, the blank is heated to 780 °C, and then subjected to air cooling after heat preservation for 15 h to obtain a heat-treated compressor blade blank.

[0074] Step 6): Finishing: The heat-treated compressor blade blank is subjected to mechanical processing to obtain a finished compressor blade.

[0075] The average grain size of the initial microstructure of the GH4068 alloy blank in this embodiment is about 5 μm, and the average grain size of the microstructure of the final compressor blade product is about 12 μm.

[0076] Embodiment 3

[0077] The method for preparing a compressor blade according to the present application comprises the following steps:

[0078] Step 1): The GH4068 alloy blank with an average grain size of 5 μm is subjected to heat preservation treatment at a temperature of 1120 °C for 1 h to obtain a blank after homogenization of the microstructure.

[0079] Step 2): After the heat preservation treatment in step 1), the blank is transferred into an extrusion rod die (the preheating temperature of the die is 300-500 °C) within 5 s, and a portion (20 mm in diameter) of the blank after homogenization of the microstructure is subjected to extrusion deformation with a deformation amount of 43.75% to form an extrusion deformation portion with a diameter of 15 mm.

[0080] Step 3): The blank after extrusion deformation of the extrusion rod is subjected to heat preservation treatment at 1120 °C for 1 h, and then is transferred into a tenon forming die (the preheating temperature of the die is 300-500 °C) within 5 s to form a tenon. The undeformed portion (20 mm in diameter) of the extrusion rod is die forged into a rhombic cross section.

[0081] Step 4): The blank is subjected to heat preservation treatment at 1120 °C for 1 h, and then is transferred into a blade pre-forging forming die (the preheating temperature of the die is 300-500 °C) within 5 s to pre-forging form a blade body from the extrusion deformation portion (Φ15 mm) of the extrusion rod, and the thickness of the blade body after pre-forging is 4 mm. The blank is subjected to heat preservation treatment at 1120 °C for 1 h, and then is transferred into a blade final forging forming die (the preheating temperature of the die is 300-500 °C) within 5 s to final forging form the blade body into a thickness of 1 mm to obtain a compressor blade blank comprising a blade body and a tenon. The compressor blade blank is cooled to room temperature, and then is subjected to edge cutting.

[0082] In addition, the strain rate in the above steps (extrusion deformation, die forging, pre-forging, and final forging) is ≥0.1 s -1 .

[0083] Step 5): The compressor blade blank is heated to 1130 °C, is subjected to oil quenching after heat preservation for 2 h, is heated to 700 °C, is subjected to air cooling after heat preservation for 16 h, and finally is heated to 750 °C, is subjected to air cooling after heat preservation for 16 h to obtain a heat-treated compressor blade blank.

[0084] Step 6) Finishing: the compressor blade blank after heat treatment is machined to obtain the compressor blade finished product.

[0085] The average grain size of the initial microstructure of the GH4068 alloy blank in this embodiment is about 5 μm, and the average grain size of the microstructure of the final compressor blade finished product is about 15 μm.

[0086] Comparative Example 1

[0087] Comparative Example 1 prepares a method for preparing a compressor blade, which mainly comprises the following steps:

[0088] Step 1) The GH4169 alloy blank with an average grain size of 10 μm is heat treated at 950 °C for 2 h to obtain the blank after microstructure homogenization treatment.

[0089] Step 2) The blank after microstructure homogenization treatment is extruded and once formed into a tenon, one end is extruded from the original diameter of 40 mm to a diameter of 20 mm, and the other end is formed into a rhombic cross section.

[0090] Step 3) Pre-forging forming: the blade body part is pre-forged from Φ20 mm to a thickness of 4 mm.

[0091] Step 4) Final forging forming: the blade body is finally forged to a thickness of 2 mm.

[0092] Step 5) Blade trimming: the blade after final forging is cooled to room temperature, and then trimmed.

[0093] Step 6) Heat treatment performance regulation: the blade is heated to 980 °C and held for 1 h, then oil quenched, then heated to 720 °C and held for 8 h, then furnace cooled, finally heated to 620 °C and held for 8 h, and then air cooled.

[0094] Step 7) Finishing: the blade blank is machined to obtain the blade finished product.

[0095] The average grain size of the initial microstructure of the blank in this embodiment is about 5 μm; and the average grain size of the microstructure of the final product is about 45 μm.

[0096] Table 1 is the microstructure performance data of the compressor blades prepared in Examples 1-3 and Comparative Example 1

[0097] Table 1

[0098]

[0099] From the above examples, the comparative examples can be seen that: (1) the present application successfully prepared the compressor blade of GH4068 alloy (the prior art has not successfully prepared); (2) the performance of the compressor blade of GH4068 alloy prepared in the present application is far superior to that of comparative example 1.

[0100] In summary, the present application provides a preparation method of the compressor blade of GH4068 alloy, which can effectively reduce the alloy deformation resistance, improve the alloy yield, and improve the uniformity of the alloy structure and performance, thereby providing a guarantee for the stable preparation of the high temperature resistance compressor blade with 750℃ high temperature resistance. The present application has simple requirements for the compressor blade preparation tooling, and can prepare the GH4068 alloy blade with 750℃ high temperature resistance on the existing GH4169 alloy blade production line with 650℃ high temperature resistance, thereby significantly reducing the production cost and being suitable for batch production.

[0101] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present application still belongs to the scope of the technical solution of the present application.

Claims

1. A method of manufacturing a compressor blade, characterized by, The compressor blade is made of GH4068 alloy; wherein the preparation method comprises the following steps: Step 1): the GH4068 alloy blank with an average grain size of 1-15 μm is kept at a temperature of 980-1120 °C for a set time to perform a microstructure homogenization treatment, thereby obtaining a blank after microstructure homogenization treatment; wherein the grain size of the blank after microstructure homogenization treatment is ≤15 μm, and the grade difference of the grain size is ≤2 grades; Step 2): after the keeping, a part of the blank after microstructure homogenization treatment is directly subjected to extrusion deformation to obtain a blank with an extrusion deformation part; wherein the extrusion deformation amount is 40-50%; Step 3): the non-deformed part on the blank with the extrusion deformation part is die forged into a tenon; wherein the diameter of the non-deformed part on the blank with the extrusion deformation part is 20-40 mm; Step 4): the extrusion deformation part is subjected to pre-die forging and finish forging treatment to form a blade body with a set thickness, thereby obtaining a compressor blade blank with a blade body and a tenon; wherein the extrusion deformation part with a diameter of 8-30 mm is pre-die forged to form a blade body with a thickness of 4-7 mm, and then is further subjected to finish forging treatment to make the thickness of the blade body be 1-3 mm; Step 5): the compressor blade blank is sequentially subjected to heat treatment and finishing, thereby obtaining a compressor blade; In any one of the steps 2) to 4), the blank needs to be subjected to reheat keeping treatment between each deformation pass, wherein the temperature of the reheat keeping treatment is 980-1120 °C; In the step of heat treatment, the compressor blade blank is heated to 1080-1130 °C, kept for 2-6 h, then subjected to quenching treatment, then heated to 600-700 °C, kept for 16-30 h, then subjected to cooling treatment, and finally heated to 750-800 °C, kept for 10-20 h, and subjected to cooling treatment; wherein the microstructure grain size of the compressor blade blank after heat treatment is within 90 μm.

2. The method of manufacturing a compressor blade according to claim 1, characterized in that, In step 1), the set time is 1-4 h.

3. The method of manufacturing a compressor blade according to claim 1, characterized in that, The tenon has a rhombic cross section.

4. The method of manufacturing a compressor blade according to claim 1, characterized by, In the step 4), after the keeping of step 1), the blank after microstructure homogenization treatment is transferred from the keeping furnace to an extrusion die within 5 s to perform extrusion deformation.

5. The preparation method of the compressor blade according to claim 1, characterized in that, After the finish forging treatment, the compressor blade blank with the blade body and the tenon is cooled to room temperature and subjected to edge cutting treatment.

6. The method of manufacturing a compressor blade according to claim 1, wherein In any one of the steps 2) to 4), The reheat keeping treatment is 1-4 h; and / or After each deformation pass, the surface of the blank needs to be checked for cracks; if cracks are generated, polishing treatment is needed to eliminate the cracks; and / or The preheating temperature of the die is 300-500 °C, and before the blank is transferred to the die, graphite lubricant needs to be sprayed in the die; and / or The time interval for transferring the blank from the keeping furnace to the die after the reheat keeping treatment is controlled to be within 5 s; and / or The microstructure grain size of the blank after each deformation pass is within 10 μm; and / or Strain rate of each deformation ≥ 0.1 s -1 .

7. The method of manufacturing a compressor blade according to claim 1, wherein In any one of the steps 2) to 4), before the heat treatment, an antioxidant is sprayed on the surface of the blank to lubricate the subsequent deformation.

8. The method of manufacturing a compressor blade according to claim 7, characterized in that The antioxidant is a glass antioxidant.

9. The method of manufacturing a compressor blade according to claim 7, wherein The thickness of the sprayed antioxidant is 0.3-0.8mm.

10. The method of manufacturing a compressor blade according to claim 1, wherein In the step of the heat treatment, the quenching treatment is oil quenching.

11. The method of manufacturing a compressor blade according to claim 1, characterized in that, In the step of the heat treatment, The cooling treatment is air cooling.

12. A compressor blade, characterized by The material of the compressor blade is GH4068 alloy; wherein the compressor blade is prepared by the preparation method of the compressor blade according to any one of claims 1-11.

13. The compressor blade of claim 12, wherein, The microstructure grain size of the compressor blade is within 90μm.

14. The compressor blade of claim 12, wherein, The GH4068 alloy comprises the following chemical elements in percentage by weight: Co 20-28wt%, Ta 0-4wt%, Cr 10-17wt%, Ti 3-7wt%, Al 0.2-5wt%, W 0.1-3wt%, Mo 0.1-5wt%, Nb 0-3wt%, Mn 0-0.5wt%, V 0-0.4wt%, C 0.005-0.1wt%, Zr 0.01-0.1wt%, B 0.001-0.1wt%, and the balance of Ni and inevitable impurities.

15. A compressor characterized by, The compressor comprises the compressor blade according to any one of claims 12-14.

Images