Vacuum brazing and heat treatment process for GH2909 alloy components

Abstract

This invention provides a vacuum brazing and heat treatment process for GH2909 alloy components, relating to the technical field of high-temperature alloy heat treatment. The method includes pre-treating the surface of the alloy component to obtain a clean surface; then placing the alloy component in a vacuum brazing furnace and evacuating it; subsequently heating the vacuum brazing furnace to perform vacuum brazing heat treatment on the alloy component, followed by furnace cooling and air cooling to obtain the vacuum brazed heat-treated alloy component; finally, performing a single aging treatment on the alloy component, followed by air cooling to obtain the final alloy component. This invention achieves short-time, high-efficiency heat treatment of the alloy component through vacuum brazing heat treatment and a single aging treatment, resulting in a synergistic improvement in the room temperature strength and stability, as well as the high-temperature strength and stability of the alloy component. The method is simple to operate, environmentally friendly, low-cost, short-process, and highly efficient, facilitating large-scale industrial production and promotion.

Description

Technical Field

[0001] This invention relates to the technical field of high-temperature alloy heat treatment, and in particular to a vacuum brazing and heat treatment process for GH2909 alloy components. Background Technology

[0002] High-temperature alloys are metallic materials based on iron, nickel, and cobalt that can work for a long time at high temperatures above 600°C and under certain stress. They have excellent high-temperature strength, good resistance to oxidation and hot corrosion, good fatigue performance, fracture toughness, and other comprehensive properties. They are also known as "superalloys" and are mainly used in the aerospace and energy fields.

[0003] GH2909 is a high-strength nickel-based alloy primarily used in engineering applications under high-temperature and corrosive environments. It typically exhibits excellent oxidation and corrosion resistance, making it suitable for critical components in aerospace, petrochemical, and other fields. The presence of nickel, chromium, iron, and molybdenum in its chemical composition allows GH2909 to maintain excellent mechanical properties and stability even at high temperatures. Applications of this alloy include gas turbine engine components, heat exchangers, and other equipment requiring high-temperature and corrosion resistance. GH2909 has relatively good machinability and can be formed and welded using various methods.

[0004] When GH2909 alloy is used in the production of welded rings, the standard short-aging heat treatment results in a large γ′ phase size and low density within the alloy matrix. Furthermore, the two-step aging process is complex. Consequently, the tensile strength and yield strength of the components sometimes fail to meet standards, or the margin of achievement is very small and unstable.

[0005] The paper "Influence of Forging Process and Heat Treatment on the Microstructure and Properties of GH2909 Alloy" (Wang Xincai, Special Steel Technology, P8-9, P14, Vol.19(75), 2013.No.2) discloses the influence of forging process and heat treatment on microstructure. It shows that the precipitates after secondary solution treatment + two-stage aging heat treatment are significantly more than those after primary solution treatment + two-stage aging heat treatment. Although the strength and hardness can be improved, the forging process needs to be limited. The temperature of solution heat treatment is not high, and the effect of solution treatment needs to be further improved. The elongation of the obtained material is low.

[0006] The paper "Research on the Heat Treatment Process Performance of GH2909" (Fan Qianwei, Sun Yan; Metal Processing: Hot Working, 2015, No. 13, pp. 18-21, 4 pages) discloses that as the solution treatment temperature increases, the strength increases while the ductility and toughness decrease; as the aging temperature increases, the strength decreases while the ductility and toughness increase. Increasing the silicon content in the raw materials is beneficial for increasing the number of ε-phase and ε″-phase in the alloy, thereby improving the alloy's high-temperature notch sensitivity. Therefore, its heat treatment process mainly consists of solution treatment and aging treatment. The ratio of these two processes is adjusted according to the required strength and ductility / toughness. Based on the aforementioned literature, at least one solution treatment followed by two-stage aging heat treatment is required. Summary of the Invention

[0007] To address the technical problems of existing GH2909 alloy components, such as poor strength and stability at room temperature and high temperature, high cost of a single solution treatment plus two aging treatments, low efficiency of a two-stage solution treatment plus two-stage aging treatment process, inability to effectively and synergistically improve strength and plasticity, and difficulty in accurately predicting the changes in strength and plasticity, this invention proposes a vacuum brazing and heat treatment process for GH2909 alloy components that can solve the aforementioned problems. The technical solution is as follows:

[0008] A vacuum brazing and heat treatment process for a GH2909 alloy component, comprising the following steps:

[0009] S1. Surface pretreatment: The surface of the GH2909 alloy parts is pretreated to obtain clean GH2909 alloy parts;

[0010] S2, Vacuuming: Place the GH2909 alloy parts with cleaned S1 surfaces in a vacuum brazing furnace and evacuate them;

[0011] S3. Vacuum brazing heat treatment: Heat the vacuum brazing furnace and perform vacuum brazing heat treatment on the GH2909 alloy parts with clean S1 surface. Then cool with the furnace and air cool after furnace cooling to obtain the GH2909 alloy parts after vacuum brazing heat treatment.

[0012] S4. First aging treatment: After vacuum brazing heat treatment in S2, the GH2909 alloy parts are subjected to a first aging treatment and air-cooled to obtain GH2909 alloy parts with improved room temperature strength and stability.

[0013] Optionally, the GH2909 alloy component in S1 is in the shape of a bar with dimensions of Φ150mm, Φ200mm, or Φ220mm, and is subjected to standard double-aging heat treatment 2 (845℃×(4±0.5)h / FC→620℃×(4±0.5)h / AC); the room temperature tensile strength is 1190-1250MPa, with a standard deviation of 18-29MPa; the room temperature yield strength is 930-960MPa, with a standard deviation of 9-17MPa; the room temperature elongation is 13.7-17.8%, with a standard deviation of 0.9-1.5%; the room temperature... The reduction of area is 22-33%, with a standard deviation of 3.9-5.8%; the room temperature hardness is 350-365 HB, with a standard deviation of 5-11 HB; the tensile strength at 650℃ is 860-970 MPa, with a standard deviation of 19-31 MPa; the yield strength at 650℃ is 715-800 MPa, with a standard deviation of 25-43 MPa; the elongation at 650℃ is 12.5-20.4%, with a standard deviation of 2.3-6.7%; and the reduction of area at 650℃ is 26.0-40.5%, with a standard deviation of 4.5-8.9%.

[0014] Optionally, the GH2909 alloy component in S1 is ring-shaped, with an outer diameter of 400-600 mm, an inner diameter of 300-500 mm, and a height of 70-90 mm. It is sampled tangentially and undergoes standard double-aging heat treatment 2 (845℃×(4±0.5)h / FC→620℃×(4±0.5)h / AC). Its room temperature tensile strength is 1200-1240 MPa, with a standard deviation of 15-27 MPa; its room temperature yield strength is 910-970 MPa, with a standard deviation of 20-45 MPa; and its room temperature elongation is 14.0-18.8%, with a standard deviation of 1.2%. -2.3%; room temperature reduction of area is 24-37%, standard deviation is 3.6-5.9%; room temperature hardness is 350-365 HB, standard deviation is 6-11 HB; tensile strength at 650℃ is 930-970 MPa, standard deviation is 20-31 MPa; yield strength at 650℃ is 770-810 MPa, standard deviation is 25-43 MPa; elongation at 650℃ is 12.5-29.4%, standard deviation is 3.8-9.7%; reduction of area at 650℃ is 26.0-44.5%, standard deviation is 6.7-10.9%.

[0015] Optionally, the GH2909 alloy component in S1 is a square billet with dimensions of 90mm × 90mm × 90mm, and is subjected to standard double-aging heat treatment 2 (845℃ × (4±0.5)h / FC → 620℃ × (4±0.5)h / AC); its room temperature tensile strength is 1200-1230MPa, with a standard deviation of 15-28MPa; its room temperature yield strength is 890-945MPa, with a standard deviation of 19-35MPa; its room temperature elongation is 14.7-18.2%, with a standard deviation of 0.7-2.1%; and its room temperature cross-section... Shrinkage rate: 26-37%, standard deviation: 2.7-5.9%; Room temperature hardness: 360-365 HB, standard deviation: 2-7 HB; Tensile strength at 650℃: 935-980 MPa, standard deviation: 15-25 MPa; Yield strength at 650℃: 784-820 MPa, standard deviation: 20-40 MPa; Elongation at 650℃: 15.5-29.4%, standard deviation: 3.8-9.3%; Reduction of area at 650℃: 27.0-47.5%, standard deviation: 6.7-11.9%.

[0016] Optionally, the pretreatment in S1 includes removing the surface oxide layer or oil stains, followed by cleaning and drying to obtain a clean GH2909 alloy part; the vacuuming in S2 involves evacuating to a pressure not exceeding 10. -3 Pa.

[0017] Optionally, in S3, the vacuum brazing heat treatment temperature is 1000-1040℃, and the holding time is 10-30 min. It needs to be heated to 550-650℃ at a rate of 10-15℃ / min and held for 10-20 min, then heated to 880-940℃ at a rate of 15-20℃ / min and held for 15-30 min, and finally heated to 1000-1040℃ at a brazing holding temperature at a rate of 5-10℃ / min. After that, it is cooled in the furnace at a rate of 3-8℃ / min, and is directly removed from the furnace when cooled to below 80℃. The air cooling rate is 50-80℃ / min, and the holding time after reaching the brazing temperature of 1000-1040℃ in this stage is 10-30 min.

[0018] Optionally, the temperature of the first aging treatment in S4 is 620±10℃, the holding time is 8±0.5h, and the heating rate is 10-30℃ / min; after that, it is taken out and air-cooled to room temperature at a rate of 50-80℃ / min.

[0019] Optionally, S3 is in bar shape with dimensions of Φ150mm, Φ200mm, or Φ220mm, and is treated by vacuum brazing + single aging ((1000-1040)℃×(15-30)min / FC+620℃×(8±0.5)h / AC); the room temperature tensile strength is 1350-1380MPa, with a standard deviation of 10-17MPa; the room temperature yield strength is 1020-1050MPa, with a standard deviation of 9-14MPa; the room temperature elongation is 17.9-23.2%, with a standard deviation of 0.8-1.7%; the room temperature... The reduction of area is 27-39%, with a standard deviation of 2.9-4.8%; the room temperature hardness is 370-385 HB, with a standard deviation of 3-8 HB; the tensile strength at 650℃ is 1005-1025 MPa, with a standard deviation of 12-26 MPa; the yield strength at 650℃ is 820-870 MPa, with a standard deviation of 25-33 MPa; the elongation at 650℃ is 11.5-21.4%, with a standard deviation of 2.3-5.7%; and the reduction of area at 650℃ is 35.0-40.5%, with a standard deviation of 2.7-4.9%.

[0020] Optionally, S3 is annular in shape, with an outer diameter of 400-600 mm, an inner diameter of 300-500 mm, and a height of 70-90 mm. Sampling is performed tangentially, and the treatment state is vacuum brazing + one aging ((1000-1040)℃×(15-30)min / FC + 620℃×(8±0.5)h / AC). The room temperature tensile strength is 1340-1370 MPa, with a standard deviation of 11-15 MPa; the room temperature yield strength is 1025-1060 MPa, with a standard deviation of 10-14 MPa; and the room temperature elongation is 18.8-24.5%, with a standard deviation of 0. 7-1.4%; room temperature reduction of area is 30-39%, standard deviation is 2.7-4.2%; room temperature hardness is 370-385 HB, standard deviation is 3-9 HB; tensile strength at 650℃ is 1000-1020 MPa, standard deviation is 12-20 MPa; yield strength at 650℃ is 830-870 MPa, standard deviation is 20-30 MPa; elongation at 650℃ is 11.5-20.4%, standard deviation is 3.7-5.1%; reduction of area at 650℃ is 35.0-41.5%, standard deviation is 2.7-3.8%.

[0021] Optionally, S3 is a square billet with dimensions of 90mm × 90mm × 90mm, and is subjected to standard double-aging heat treatment 2 (845℃ × (4±0.5)h / FC → 620℃ × (4±0.5)h / AC); the room temperature tensile strength is 1200-1230MPa, with a standard deviation of 15-28MPa; the room temperature yield strength is 890-945MPa, with a standard deviation of 19-35MPa; the room temperature elongation is 14.7-18.2%, with a standard deviation of 0.7-2.1%; and the room temperature reduction of area is 26%. -37%, standard deviation 2.7-5.9%; room temperature hardness 360-365 HB, standard deviation 2-7 HB; tensile strength at 650℃ 935-980 MPa, standard deviation 15-25 MPa; yield strength at 650℃ 784-820 MPa, standard deviation 20-40 MPa; elongation at 650℃ 15.5-29.4%, standard deviation 3.8-9.3%; reduction of area at 650℃ 27.0-47.5%, standard deviation 6.7-11.9%.

[0022] Optionally, the final microstructure of the GH2909 alloy component after vacuum brazing and one aging process consists of 79.70-80.44% γ solid solution (by volume), 12.97-13.43% γ′ phase (by volume), 4.06-5.36% Laves phase (by volume), and 1.86-2.06% ε phase (γ solid solution is generally not studied, and its shape and size are not fixed); wherein, the γ′ phase is shaped as fine spheres or cubic, with an average size of 18.46 nm; the Laves phase is shaped as spheres or short rods, with an average major axis length of 1.45-1.84 μm and an average minor axis length of 0.75-0.86 μm; and the ε phase is shaped as needles, with an average length of 0.89-1.61 μm.

[0023] Technical principle of the invention:

[0024] In the vacuum brazing heat treatment and aging process of this invention:

[0025] Firstly, during the vacuum brazing stage, to protect the heating components inside the vacuum brazing furnace and ensure their normal service life, a lower heating power and a segmented heating method are adopted: 1. Heating to 550-650℃ at a rate of 10-15℃ / min and holding for 10-20 minutes. The precipitation temperature of the alloy's strengthening phase γ′ is approximately 560-720℃, and the precipitation temperature of the ε phase is 680-800℃, which is a softening phase. Therefore, during the first stage of holding, a portion of the γ′ phase precipitates in the alloy, but the ε phase does not precipitate, ensuring that the strength and hardness of the alloy component meet the support requirements throughout the brazing process; 2. Continuing to heat to 880-940℃ at a rate of 15-20℃ / min and holding for 15-30 minutes. The main purpose is to ensure a more uniform temperature inside the furnace before the brazing process begins, avoiding temperature unevenness during brazing. During this process, a portion of the Laves phase precipitates at the grain boundaries, which acts as a grain boundary anchor and strengthens the alloy. The grain boundary effect ensures the plasticity of the alloy parts during the brazing process; 3. The temperature is raised to 1000-1040℃ (brazing temperature) at a rate of 5-10℃ / min and held for 10-30min for brazing. The standard solution temperature of GH2909 alloy in the alloy handbook is 980℃, and the complete dissolution temperature of the Laves phase is 1050℃. Therefore, this brazing process is equivalent to a solution heat treatment, but some Laves phases are not dissolved and are intermittently distributed at the grain boundaries in a small size; The cooling rate stage adopts furnace cooling at a rate of 3-8℃ / min. The vacuum brazing furnace has vacuum characteristics, so it is not easy to directly take out the sample for cooling. Therefore, the conventional method used before was to introduce Ar gas for cooling (cooling rate of about 100℃ / min). However, according to the CCT curve results of the alloy, this cooling rate cannot cause the γ′ phase to precipitate. This invention adopts furnace cooling to actively reduce the cooling rate, so that the fine γ′ phase is first dispersed and precipitated in the alloy.

[0026] Then comes the aging stage. To protect the heating furnace and reduce energy consumption, a simple, low-temperature single aging process is adopted: the temperature is raised to 620±10℃ at a rate of 10-30℃ / min and held for 8±0.5h, then removed and air-cooled. The conventional method before brazing is standard short-time double aging (745℃×(4±0.5)h / FC→620℃×(4±0.5)h / AC), which is complex and results in a large cubic γ′ phase, which generally does not contribute much to strength. The single aging of this invention, at a lower temperature, does not cause the γ′ phase precipitated during the post-weld cooling stage to grow excessively, and is accompanied by additional precipitation. The strength improvement is higher than that of commonly used heat treatment, and the overall plasticity is still good.

[0027] In summary, the selection of the heating rate is mainly to protect the normal operation of the vacuum brazing furnace and the heating furnace, and to maintain the temperature inside the furnace as uniform as possible when the heating power is sufficient. As for the selection of the cooling rate, only furnace cooling with a reduced cooling rate after brazing has an impact on the microstructure of the alloy, as explained above. The selection of air cooling for subsequent aging is based on national standards and has little impact on the alloy microstructure.

[0028] The above technical solution has at least the following advantages compared with the existing technology:

[0029] The above-mentioned solution, proposed by this invention, provides a vacuum brazing and heat treatment process for GH2909 alloy components. This process addresses the technical problems of existing technologies, such as poor strength and stability at room temperature and high temperature, high cost of a single solution treatment plus two aging treatments, low efficiency of a two-stage solution treatment plus two-stage aging treatment process, inability to effectively improve strength and plasticity in a synergistic manner, and difficulty in accurately predicting the changes in strength and plasticity.

[0030] This invention replaces processes such as one solution treatment and two aging treatments, or two solution treatments and two aging treatments, with vacuum brazing heat treatment and one aging treatment, thus shortening the process flow, reducing process costs, and improving process efficiency.

[0031] This invention regulates the heating and cooling rates during vacuum brazing heat treatment and aging treatment, resulting in a significant and uniform precipitation of the γ′ phase in the alloy during the cooling stage after vacuum brazing heat treatment, and further precipitation during one-step aging heat treatment, without excessive microstructure growth or phase transformation. This heat treatment improves the uniformity of the γ′ phase distribution within the grains, resulting in unexpected improvements in the strength and stability of the alloy components.

[0032] Multiple sets of mechanical property test results of this invention show that, compared with traditional brazing and aging processes, the room temperature tensile strength and yield strength of the alloy are increased by 120 and 90 MPa respectively after treatment using the method described in this invention, and the standard deviation of the room temperature yield strength is reduced by more than 30%.

[0033] In summary, compared with other traditional methods, the method of the present invention performs short-time and efficient heat treatment on GH2909 alloy parts through vacuum brazing heat treatment and one-time aging treatment, which synergistically improves the room temperature strength and stability, as well as the high temperature strength and stability of the alloy parts. The method is simple to operate, environmentally friendly, low in cost, short in process, and highly efficient, which is conducive to large-scale industrial production and promotion. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a distribution diagram of the γ′ phase in the alloy obtained by vacuum brazing and heat treatment process of a GH2909 alloy component according to Embodiment 1 of the present invention.

[0036] Figure 2 This is a distribution diagram of the γ′ phase in the alloy obtained by comparative example 1 of the present invention after vacuum brazing heat treatment + double aging process. Detailed Implementation

[0037] The technical solution of the present invention will now be described with reference to the accompanying drawings.

[0038] In embodiments of the present invention, words such as "exemplarily," "for example," etc., are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" in the present invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the word "exemplary" is intended to present the concept in a concrete manner. Furthermore, in embodiments of the present invention, the meaning expressed by "and / or" can be both, or either one.

[0039] In the embodiments of the present invention, the terms "image" and "picture" may sometimes be used interchangeably. It should be noted that when the distinction is not emphasized, their intended meanings are consistent.

[0040] In this embodiment of the invention, sometimes a subscript such as W1 may be written in a non-subscript form such as W1. When the difference is not emphasized, the meaning they express is the same.

[0041] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0042] Example 1

[0043] A vacuum brazing and heat treatment process for a GH2909 alloy component, wherein the elemental composition by mass percentage is: C 0.01%, Si 0.40%, Co 13.48%, Ni 38.06%, Ti 1.64%, Nb 4.88%, Al 0.031%, Mo 0.04%, with the balance being Fe and unavoidable impurities; the vacuum brazing and heat treatment process for the GH2909 alloy component is as follows:

[0044] S1. Surface Pretreatment: The surface of the GH2909 alloy component is pretreated to remove the oxide layer or oil stains. Finally, it is cleaned and dried to obtain a clean GH2909 alloy component. The GH2909 alloy component is rod-shaped with a size of Φ150mm and a sampling size of Φ8mm. The condition before brazing is standard short-time double aging 2. The mechanical properties are shown in Table 1 below.

[0045] Table 1

[0046] Test temperature / ℃ Tensile strength / MPa Standard deviation / MPa room temperature 1211、1192、1242、1228、1250、1219 19.3 650 900、865、885、935、895、921 22.8 Test temperature / ℃ Yield strength / MPa Standard deviation / MPa room temperature 960、931、953、942、935、945 9.9 650 750、725、734、804、779、781 28.0 Test temperature / ℃ Elongation / % Standard deviation / % room temperature 13.5、15.4、17.1、14.4、15.4、14.1 1.2 650 11.5、12.7、17.5、21.2、24、16 4.4 Test temperature / ℃ Post-fracture shrinkage rate / % Standard deviation / % room temperature 26、33、37、28、31、22 4.8 650 24、37、31、38、38、27 5.5 Test temperature / ℃ Hardness / HB Standard deviation / HB room temperature 361.1、373.3、368.5、359.1、360.1、367.5 5.2 ;

[0047] S2. Vacuuming: Place the GH2909 alloy parts (cleaned from surface S1) in a vacuum brazing furnace and evacuate to a pressure not exceeding 10. -3 Pa;

[0048] S3. Vacuum Brazing Heat Treatment: The vacuum brazing furnace is heated to perform vacuum brazing heat treatment on the GH2909 alloy parts with clean S1 surfaces. The temperature of the vacuum brazing heat treatment is 1000℃, and it is held for 30 minutes. The temperature is then increased to 550℃ at a rate of 10℃ / min and held for 10 minutes. The temperature is then increased to 940℃ at a rate of 15℃ / min and held for 10 minutes. Finally, the temperature is increased to 1000℃ at a rate of 5℃ / min. After brazing, the parts are cooled in the furnace at a rate of 3℃ / min. They are then cooled to 80℃ and air-cooled to room temperature at a rate of 70℃ / min to obtain the GH2909 alloy parts after vacuum brazing treatment.

[0049] S4. First aging treatment: The GH2909 alloy parts after S3 vacuum brazing heat treatment are subjected to a first aging treatment at a temperature of 620℃ for 8 hours, with a heating rate of 20℃ / min. After aging, the parts are taken out and air-cooled to room temperature at a rate of 70℃ / min. The GH2909 alloy parts are obtained after air cooling.

[0050] The GH2909 alloy component in this embodiment is rod-shaped with a diameter of Φ150mm and a sample size of Φ8mm. After vacuum brazing and one aging process, its mechanical properties are shown in Table 2 below.

[0051] Table 2

[0052] Test temperature / ℃ Tensile strength / MPa Standard deviation / MPa room temperature 1381、1385、1377、1368、1370、1375 5.9 650 1010、999、1020、1012、1015、1016 4.9 Test temperature / ℃ Yield strength / MPa Standard deviation / MPa room temperature 1024、1031、1025、1019、1034、1029 6.6 650 831、824、829、815、826、815 6.3 Test temperature / ℃ Elongation / % Standard deviation / % room temperature 19.1、19.1、20.4、21.5、18.9、20.1 0.9 650 12.4、11.6、13.8、23.0、17.5、15.5 3.8 Test temperature / ℃ Post-fracture shrinkage rate / % Standard deviation / % room temperature 35、34、30、33、37、36 2.3 650 36、38、41、37、38、39 1.6 Test temperature / ℃ Hardness / HB Standard deviation / HB room temperature 381.3、373.3、377.8、379.1、382.4、378.8 2.9 ;

[0053] like Figure 1As shown, the microstructure of the GH2909 alloy component prepared in this embodiment after vacuum brazing and one aging consists of 80.66% γ solid solution, 13.05% γ′ phase, 4.32% Laves phase, and 1.97% ε phase (γ solid solution is generally not studied, and its shape and size are not fixed); among them, the γ′ phase is shaped as small spheres or cubic, with an average size of 18.41 nm; the Laves phase is shaped as spheres or short rods, with an average major axis length of 1.46 μm and an average minor axis length of 0.77 μm; the ε phase is shaped as needles, with an average length of 1.53 μm.

[0054] Comparative Example 1

[0055] A vacuum brazing and heat treatment process for a GH2909 alloy component, wherein the elemental composition by mass percentage is: C 0.01%, Si 0.40%, Co 13.48%, Ni 38.06%, Ti 1.64%, Nb 4.88%, Al 0.031%, Mo 0.04%, with the balance being Fe and unavoidable impurities; the vacuum brazing and heat treatment process for the GH2909 alloy component is as follows:

[0056] S1. Surface Pretreatment: The surface of the GH2909 alloy part is pretreated to remove the oxide layer or oil stains. Finally, it is cleaned and dried to obtain a clean GH2909 alloy part. The GH2909 alloy part is rod-shaped with a size of Φ150mm and a sampling size of Φ8mm. The condition before brazing is standard short-time double aging 2. The mechanical properties are shown in Table 3 below.

[0057] Table 3

[0058]

[0059]

[0060] S2. Vacuuming: Place the GH2909 alloy parts (cleaned from surface S1) in a vacuum brazing furnace and evacuate to a pressure not exceeding 10. -3 Pa;

[0061] S3. Vacuum Brazing Heat Treatment: The vacuum brazing furnace is heated to perform vacuum brazing heat treatment on the GH2909 alloy parts with clean S1 surfaces. The temperature of the vacuum brazing heat treatment is 1000℃, and it is held for 30 minutes. The temperature is then increased to 550℃ at a rate of 10℃ / min and held for 10 minutes. The temperature is then increased to 940℃ at a rate of 15℃ / min and held for 10 minutes. Finally, the temperature is increased to 1000℃ at a rate of 5℃ / min. After brazing, Ar gas is introduced for rapid cooling at a rate of 100℃ / min. The parts are cooled to below 80℃ and then air-cooled to room temperature at a rate of 70℃ / min to obtain the GH2909 alloy parts after vacuum brazing treatment.

[0062] S4. Two aging treatments: The GH2909 alloy parts after S3 vacuum brazing heat treatment are subjected to two aging treatments. The temperature is raised to 745℃ at a rate of 20℃ / min and held for 4 hours. Then, the temperature is cooled to 620℃ at a rate of 55℃ / h and held for 4 hours. Finally, the parts are taken out and air-cooled to room temperature at a rate of 50-80℃ / min to obtain the GH2909 alloy parts.

[0063] The GH2909 alloy component in this comparative example is in bar shape, with a dimension of Φ150mm and a sampling size of Φ8mm. Its room temperature tensile strength is 1210-1250MPa, with a standard deviation of 15-27MPa; its room temperature yield strength is 920-955MPa, with a standard deviation of 7-15MPa; its room temperature elongation is 14.7-19.8%, with a standard deviation of 0.7-1.2%; and its room temperature reduction of area is 24-37%, with a standard deviation of 2.9-5.6%. The hardness at 650℃ is 357-365 HB, with a standard deviation of 5-8 HB; the tensile strength at 650℃ is 880-950 MPa, with a standard deviation of 17-33 MPa; the yield strength at 650℃ is 745-800 MPa, with a standard deviation of 26-40 MPa; the elongation at 650℃ is 14.5-21.8%, with a standard deviation of 2.4-7.7%; and the reduction of area at 650℃ is 27.0-42.5%, with a standard deviation of 4.7-9.2%.

[0064] like Figure 2 As shown, the microstructure of the GH2909 alloy component in this comparative example after vacuum brazing and one aging process consists of 72.25% γ solid solution, 20.41% γ′ phase, 4.67% Laves phase, and 2.67% ε phase (γ solid solution is generally not studied, and its shape and size are not fixed); among them, the γ′ phase is cubic in shape with an average size of 29.38 nm; the Laves phase is spherical or short rod-shaped with an average major axis length of 1.56 μm and an average minor axis length of 0.79 μm; and the ε phase is needle-shaped with an average length of 1.74 μm.

[0065] and Figure 1 Compared to the heat treatment process shown in the embodiment, the distribution of the γ′ phase in the alloy after heat treatment is different. Figure 2 The alloy in Comparative Example 1, after processing, has a lower density of γ′ phase and a larger size.

[0066] A comparison of the strength values ​​in Comparative Example 1 and Example 1 shows that the GH2909 alloy parts treated with the process described in this invention exhibit a significant increase in strength compared to those treated with traditional standard aging treatment. The tensile strength increases by an average of approximately 100 MPa, and the yield strength increases by an average of approximately 90 MPa. Furthermore, the mechanical property stability of the GH2909 alloy is significantly improved after treatment using the heat treatment process of this invention. The standard deviation of the room temperature yield strength is reduced by more than 40%. This solves the technical problem of GH2909 alloy parts failing to meet strength standards or having a small margin of compliance during actual production.

[0067] Comparative Example 2

[0068] A vacuum brazing and heat treatment process for a GH2909 alloy component, wherein the elemental composition by mass percentage is: C 0.01%, Si 0.40%, Co 13.48%, Ni 38.06%, Ti 1.64%, Nb 4.88%, Al 0.031%, Mo 0.04%, with the balance being Fe and unavoidable impurities; the vacuum brazing and heat treatment process for the GH2909 alloy component is as follows:

[0069] S1. Surface Pretreatment: The surface of the GH2909 alloy component is pretreated to remove the oxide layer or oil stains. Finally, it is cleaned and dried to obtain a clean GH2909 alloy component. The GH2909 alloy component is rod-shaped with a size of Φ150mm and a sampling size of Φ8mm. The condition before brazing is standard short-time double aging 2. The mechanical properties are shown in Table 4 below.

[0070] Table 4

[0071] Test temperature / ℃ Tensile strength / MPa Standard deviation / MPa room temperature 1211、1192、1242、1228、1250、1219 19.3 650 900、865、885、935、895、921 22.8 Test temperature / ℃ Yield strength / MPa Standard deviation / MPa room temperature 960、931、953、942、935、945 9.9 650 750、725、734、804、779、781 28.0 Test temperature / ℃ Elongation / % Standard deviation / % room temperature 13.5、15.4、17.1、14.4、15.4、14.1 1.2 650 11.5、12.7、17.5、21.2、24、16 4.4 Test temperature / ℃ Post-fracture shrinkage rate / % Standard deviation / % room temperature 26、33、37、28、31、22 4.8 650 24、37、31、38、38、27 5.5 Test temperature / ℃ Hardness / HB Standard deviation / HB room temperature 361.1、373.3、368.5、359.1、360.1、367.5 5.2 ;

[0072] S2. Vacuuming: Place the GH2909 alloy parts (cleaned from surface S1) in a vacuum brazing furnace and evacuate to a pressure not exceeding 10. -3 Pa;

[0073] S3. Vacuum Brazing Heat Treatment: The vacuum brazing furnace is heated to perform vacuum brazing heat treatment on the GH2909 alloy parts with clean S1 surfaces. The vacuum brazing heat treatment temperature is 1010℃, and the holding time is 25 min. The temperature is then increased to 560℃ at a rate of 15℃ / min and held for 10 min. The temperature is then increased to 920℃ at a rate of 20℃ / min and held for 10 min. Finally, the temperature is increased to 1010℃ at a rate of 7℃ / min. After brazing, the parts are cooled in the furnace at a cooling rate of 4℃ / min. The parts are then cooled to 80℃ and air-cooled to room temperature at a cooling rate of 70℃ / min to obtain the GH2909 alloy parts after vacuum brazing treatment.

[0074] S4. Two aging treatments: The GH2909 alloy parts after S3 vacuum brazing heat treatment are subjected to two aging treatments. The temperature is raised to 745℃ at a rate of 20℃ / min and held for 4 hours. Then, the temperature is cooled to 620℃ at a rate of 55℃ / h and held for 4 hours. Finally, the parts are taken out and air-cooled to room temperature at a rate of 50-80℃ / min to obtain the GH2909 alloy parts.

[0075] The GH2909 alloy component in this comparative example is a bar with a diameter of Φ150mm and a sample size of Φ8mm. Its room temperature tensile strength is 1180-1240MPa, with a standard deviation of 15-27MPa; its room temperature yield strength is 920-955MPa, with a standard deviation of 7-15MPa; its room temperature elongation is 14.7-19.8%, with a standard deviation of 0.7-1.2%; and its room temperature reduction of area is 24-37%, with a standard deviation of 2.9-5.6%. The hardness at 650℃ is 357-365 HB, with a standard deviation of 5-8 HB; the tensile strength at 650℃ is 880-950 MPa, with a standard deviation of 17-33 MPa; the yield strength at 650℃ is 745-800 MPa, with a standard deviation of 26-40 MPa; the elongation at 650℃ is 14.5-21.8%, with a standard deviation of 2.4-7.7%; and the reduction of area at 650℃ is 27.0-42.5%, with a standard deviation of 4.7-9.2%.

[0076] The microstructure of the GH2909 alloy component prepared in this comparative example, after vacuum brazing and two aging processes, consists of 74.93% γ solid solution, 18.11% γ′ phase, 4.78% Laves phase, and 2.18% ε phase (γ solid solution is generally not studied, and its shape and size are not fixed). Among them, the γ′ phase is cubic in shape with an average size of 32.77 nm; the Laves phase is spherical or short rod-shaped with an average major axis length of 1.72 μm and an average minor axis length of 0.81 μm; and the ε phase is needle-shaped with an average length of 1.69 μm.

[0077] Comparative Example 3

[0078] A vacuum brazing and heat treatment process for a GH2909 alloy component, wherein the elemental composition by mass percentage is: C 0.01%, Si 0.40%, Co 13.48%, Ni 38.06%, Ti 1.64%, Nb 4.88%, Al 0.031%, Mo 0.04%, with the balance being Fe and unavoidable impurities; the vacuum brazing and heat treatment process for the GH2909 alloy component is as follows:

[0079] S1. Surface Pretreatment: The surface of the GH2909 alloy component is pretreated to remove the oxide layer or oil stains. Finally, it is cleaned and dried to obtain a clean GH2909 alloy component. The GH2909 alloy component is rod-shaped with a dimension of Φ150mm and a sampling dimension of Φ8mm. Before brazing, it is in a standard short-time double-aging state (2). Its mechanical properties are shown in Table 5 below.

[0080] Table 5

[0081] Test temperature / ℃ Tensile strength / MPa Standard deviation / MPa room temperature 1211、1192、1242、1228、1250、1219 19.3 650 900、865、885、935、895、921 22.8 Test temperature / ℃ Yield strength / MPa Standard deviation / MPa room temperature 960、931、953、942、935、945 9.9 650 750、725、734、804、779、781 28.0 Test temperature / ℃ Elongation / % Standard deviation / % room temperature 13.5、15.4、17.1、14.4、15.4、14.1 1.2 650 11.5、12.7、17.5、21.2、24、16 4.4 Test temperature / ℃ Post-fracture shrinkage rate / % Standard deviation / % room temperature 26、33、37、28、31、22 4.8 650 24、37、31、38、38、27 5.5 Test temperature / ℃ Hardness / HB Standard deviation / HB room temperature 361.1、373.3、368.5、359.1、360.1、367.5 5.2 ;

[0082] S2. Vacuuming: Place the GH2909 alloy parts (cleaned from surface S1) in a vacuum brazing furnace and evacuate to a pressure not exceeding 10. -3 Pa;

[0083] S3. Vacuum Brazing Heat Treatment: The vacuum brazing furnace is heated to perform vacuum brazing heat treatment on the GH2909 alloy parts with clean S1 surfaces. The temperature of the vacuum brazing heat treatment is 1000℃, and it is held for 25 minutes. The temperature is then increased to 560℃ at a rate of 15℃ / min and held for 10 minutes. The temperature is then increased to 920℃ at a rate of 20℃ / min and held for 10 minutes. Finally, the temperature is increased to 1000℃ at a rate of 7℃ / min. After brazing, the parts are cooled in the furnace at a cooling rate of 3℃ / min. They are then cooled to 80℃ and air-cooled to room temperature at a cooling rate of 70℃ / min to obtain the GH2909 alloy parts after vacuum brazing treatment.

[0084] S4. Two aging treatments: The GH2909 alloy parts after S3 vacuum brazing heat treatment are subjected to two aging treatments. The temperature is raised to 745℃ at a rate of 20℃ / min and held for 4 hours. Then, they are removed and water-cooled at a rate of 50℃ / s. The temperature is then raised to 620℃ at a rate of 20℃ / min and held for 4 hours. Finally, they are removed and air-cooled at a rate of 70℃ / min. This results in GH2909 alloy parts with improved room temperature strength and stability.

[0085] The GH2909 alloy component in this comparative example is a bar stock with a diameter of 150 mm and a sample size of 8 mm. Its room temperature tensile strength is 1170-1220 MPa, with a standard deviation of 13-26 MPa; its room temperature yield strength is 910-945 MPa, with a standard deviation of 5-13 MPa; its room temperature elongation is 16.7-20.8%, with a standard deviation of 0.9-1.7%; and its room temperature reduction of area is 25-38%, with a standard deviation of 1.8-5.4%. The hardness at 650℃ is 360-369 HB, with a standard deviation of 5-9 HB; the tensile strength at 650℃ is 880-945 MPa, with a standard deviation of 17-40 MPa; the yield strength at 650℃ is 750-800 MPa, with a standard deviation of 26-37 MPa; the elongation at 650℃ is 13.7-20.8%, with a standard deviation of 2.7-5.9%; and the reduction of area at 650℃ is 26.7-44.2%, with a standard deviation of 2.9-8.2%.

[0086] The microstructure of the GH2909 alloy component in this comparative example, after vacuum brazing and two aging processes, consists of 70.55% γ solid solution, 22.44% γ′ phase, 4.76% Laves phase, and 2.25% ε phase (γ solid solution is generally not studied, and its shape and size are not fixed). Among them, the γ′ phase is cubic in shape with an average size of 33.57 nm; the Laves phase is spherical or short rod-shaped with an average major axis length of 1.69 μm and an average minor axis length of 0.76 μm; and the ε phase is needle-shaped with an average length of 1.89 μm.

[0087] Comparing Example 1 and Comparative Example 1, Example 1 optimizes the cooling method and subsequent heat treatment method after vacuum brazing in Comparative Example 1, using slower furnace cooling instead of rapid cooling with Ar gas, and using low-temperature single aging instead of the traditional double aging process; comparing Example 1 and Comparative Example 2, Example 1 optimizes the heat treatment method after brazing in Comparative Example 2, using low-temperature single aging instead of the traditional double aging heat treatment; comparing Example 1 and Comparative Example 3, Example 1 optimizes the heat treatment method after brazing in Comparative Example 3, using low-temperature single aging instead of the staged double aging heat treatment.

[0088] Compared with Comparative Examples 1-3, Example 1 optimized the process steps and resulted in the precipitation of extremely dense fine γ′ phases in the alloy matrix. Through data, we can find that the γ′ phase size in Example 1 is much smaller than that in Comparative Examples 1-3, and the strength is improved while the plasticity is comparable.

[0089] This invention proposes a vacuum brazing and heat treatment process suitable for GH2909 alloy, based on practical production conditions. Compared with multiple brazing processes, it reduces the coarsening of the Laves phase and the grain growth of alloy parts caused by Laves phase re-dissolution. Due to the limitations of vacuum conditions, alloy parts cannot be immediately removed for air cooling. This invention utilizes this stage to allow the alloy to be furnace-cooled, appropriately reducing the cooling rate and controlling the small amount of γ′ phase precipitation. A subsequent one-step aging process simplifies the traditional standard aging process. This solves the problem that the tensile strength and yield strength of forgings sometimes fail to meet standards or have very small and unstable allowances.

[0090] Compared with traditional standard heat treatment processes, the heat treatment described in this invention employs a one-step aging process, replacing the relatively complex two-step aging process while maintaining the same aging time. The γ′ phase of the alloy precipitates densely during the cooling stage after solution treatment, and is further supplemented during the one-step aging heat treatment process, without excessive growth or phase transformation. After this heat treatment, the uniformity of the γ′ phase distribution within the grains is improved, resulting in unexpected effects on enhancing the strength and stability of the alloy components. Multiple sets of mechanical property test results show that, compared with traditional brazing and aging processes, the alloy treated using the method described in this invention exhibits an increase of 120 MPa and 90 MPa in room temperature tensile strength and yield strength, respectively, and a reduction of over 30% in the standard deviation of room temperature yield strength.

[0091] Example 2

[0092] A vacuum brazing and heat treatment process for a GH2909 alloy component, wherein the GH2909 alloy used is in rod shape with a size of Φ200mm, and the elemental composition by mass percentage is: C 0.022%, Si 0.26%, Co 14.08%, Ni 37.66%, Ti 1.67%, Nb 5.09%, Al 0.12%, Mo 0.50%, with the balance being Fe and unavoidable impurities; the vacuum brazing and heat treatment process for the GH2909 alloy component is as follows:

[0093] S1. Surface Pretreatment: The surface of the GH2909 alloy part is pretreated to remove the oxide layer or oil stains. Finally, it is cleaned and dried to obtain a clean GH2909 alloy part. The GH2909 alloy part is rod-shaped with a size of Φ200mm and a sampling size of Φ8mm. The condition before brazing is standard short-time double aging 2. The mechanical properties are shown in Table 6 below.

[0094] Table 6

[0095] Test temperature / ℃ Tensile strength / MPa Standard deviation / MPa room temperature 1211、1197、1232、1250、1228、1219 16.7 650 901、868、897、934、893、927 21.9 Test temperature / ℃ Yield strength / MPa Standard deviation / MPa room temperature 959、942、954、939、937、948 7.9 650 751、734、774、805、769、800 24.8 Test temperature / ℃ Elongation / % Standard deviation / % room temperature 13.7、15.4、18.1、14.4、15.2、14.3 1.4 650 11.7、12.7、16.5、21.2、22.8、15.2 4.1 Test temperature / ℃ Post-fracture shrinkage rate / % Standard deviation / % room temperature 25、33、37、28、31、27 4.0 650 28、37、31、38、38、29 4.2 Test temperature / ℃ Hardness / HB Standard deviation / HB room temperature 361.1、373.3、368.5、359.1、360.1、367.5 5.2 ;

[0096] S2. Vacuuming: Place the GH2909 alloy parts (cleaned from surface S1) in a vacuum brazing furnace and evacuate to a pressure not exceeding 10. -3 Pa;

[0097] S3. Vacuum Brazing Heat Treatment: The vacuum brazing furnace is heated to perform vacuum brazing heat treatment on the GH2909 alloy parts with clean S1 surfaces. The temperature of the vacuum brazing heat treatment is 1000℃, and it is held for 25 minutes. The temperature is then increased to 550℃ at a rate of 15℃ / min and held for 10 minutes. The temperature is then increased to 940℃ at a rate of 20℃ / min and held for 10 minutes. Finally, the temperature is increased to 1000℃ at a rate of 7℃ / min. After brazing, the parts are cooled in the furnace at a rate of 3℃ / min. They are then cooled to 80℃ and air-cooled to room temperature at a rate of 70℃ / min to obtain the GH2909 alloy parts after vacuum brazing treatment.

[0098] S4. First aging treatment: The GH2909 alloy parts after S3 vacuum brazing heat treatment are subjected to a first aging treatment at a temperature of 630℃ for 7.5h, with a heating rate of 10℃ / min and an air cooling rate of 70℃ / min. This results in GH2909 alloy parts with improved room temperature strength and stability.

[0099] In this embodiment, the GH2909 alloy component is rod-shaped with a diameter of Φ200mm and a sample size of Φ8mm. After vacuum brazing and one aging process, the mechanical properties are shown in Table 7 below.

[0100] Table 7

[0101] Test temperature / ℃ Tensile strength / MPa Standard deviation / MPa room temperature 1382、1379、1384、1369、1389、1374 6.5 650 1015、1011、1008、998、1014、1021 7.1 Test temperature / ℃ Yield strength / MPa Standard deviation / MPa room temperature 1024、1031、1035、1028、1039、1027 5.1 650 840、824、827、834、822、831 6.1 Test temperature / ℃ Elongation / % Standard deviation / % room temperature 19.1、20.1、20.4、21.5、19.9、19.7 0.7 650 18.4、17.6、20.8、23.1、18.9、13.5 2.9 Test temperature / ℃ Post-fracture shrinkage rate / % Standard deviation / % room temperature 35、34、33、33、37、36 1.5 650 36、38、42、37、40、39 2.0 Test temperature / ℃ Hardness / HB Standard deviation / HB room temperature 381.3、373.3、377.8、376.2、382.6、378.8 2.9 ;

[0102] The microstructure of the GH2909 alloy component in this embodiment, after vacuum brazing and one aging process, consists of 82.00% γ solid solution, 11.99% γ′ phase, 4.32% Laves phase, and 1.69% ε phase (γ solid solution is generally not studied, and its shape and size are not fixed). Among them, the γ′ phase is shaped as small spheres or cubic, with an average size of 17.69 nm; the Laves phase is shaped as spheres or short rods, with an average major axis length of 1.52 μm and an average minor axis length of 0.70 μm; and the ε phase is shaped as needles with an average length of 1.51 μm.

[0103] Example 3

[0104] A vacuum brazing and heat treatment process for a GH2909 alloy component, wherein the GH2909 alloy used is in rod shape with a size of Φ220mm, and the elemental composition by mass percentage is as follows: C 0.01%, Si 0.38%, Co 13.42%, Ni 37.64%, Ti 1.55%, Nb 4.68%, Al 0.039%, Mo 0.03%, with the balance being Fe and unavoidable impurities; the vacuum brazing and heat treatment process for the GH2909 alloy component is as follows:

[0105] S1. Surface Pretreatment: The surface of the GH2909 alloy part is pretreated to remove the oxide layer or oil stains. Finally, it is cleaned and dried to obtain a clean GH2909 alloy part. The GH2909 alloy part is rod-shaped with a size of Φ220mm and a sampling size of Φ8mm. The condition before brazing is standard short-time double aging 2. The mechanical properties are shown in Table 8 below.

[0106] Table 8

[0107]

[0108]

[0109] S2. Vacuuming: Place the GH2909 alloy parts (cleaned from surface S1) in a vacuum brazing furnace and evacuate to a pressure not exceeding 10. -3 Pa;

[0110] S3. Vacuum Brazing Heat Treatment: The vacuum brazing furnace is heated to perform vacuum brazing heat treatment on the GH2909 alloy parts with clean S1 surfaces. The temperature of the vacuum brazing heat treatment is 1020℃, and it is held for 15 minutes. The temperature is then increased to 580℃ at a rate of 15℃ / min and held for 10 minutes. The temperature is then increased to 930℃ at a rate of 20℃ / min and held for 10 minutes. Finally, the temperature is increased to 1020℃ at a rate of 10℃ / min. After brazing, the parts are cooled in the furnace at a rate of 3℃ / min. They are then cooled to 80℃ and air-cooled to room temperature at a rate of 70℃ / min to obtain the GH2909 alloy parts after vacuum brazing treatment.

[0111] S4. First aging treatment: The GH2909 alloy parts after S3 vacuum brazing heat treatment are subjected to a first aging treatment at a temperature of 620℃ for 8 hours. The heating rate is 15℃ / min, and the air cooling rate is 70℃ / min. After air cooling, GH2909 alloy parts with improved room temperature strength and stability are obtained.

[0112] In this embodiment, the GH2909 alloy component is rod-shaped with a diameter of Φ220mm and a sample size of Φ8mm. After vacuum brazing and one aging process, its mechanical properties are shown in Table 9 below.

[0113] Table 9

[0114]

[0115]

[0116] The microstructure of the GH2909 alloy component in this embodiment, after vacuum brazing and one aging process, consists of 80.07% γ solid solution, 13.79% γ′ phase, 4.44% Laves phase, and 1.70% ε phase (γ solid solution is generally not studied, and its shape and size are not fixed). Among them, the γ′ phase is shaped as small spheres or cubic, with an average size of 18.54 nm; the Laves phase is shaped as spheres or short rods, with an average major axis length of 1.60 μm and an average minor axis length of 0.75 μm; and the ε phase is shaped as needles with an average length of 1.31 μm.

[0117] Example 4

[0118] A vacuum brazing and heat treatment process for a GH2909 alloy component, wherein the GH2909 alloy used is a ring with an outer diameter of 600 mm, an inner diameter of 500 mm, and a height of 70 mm. The elemental composition by mass percentage is as follows: C 0.01%, Si 0.39%, Co 13.49%, Ni 38.05%, Ti 1.62%, Nb 4.78%, Al 0.031%, Mo 0.04%, with the balance being Fe and unavoidable impurities. The vacuum brazing and heat treatment process for the GH2909 alloy component is as follows:

[0119] S1. Surface Pretreatment: The surface of the GH2909 alloy part is pretreated to remove the oxide layer or oil stains. Finally, it is cleaned and dried to obtain a clean GH2909 alloy part. The GH2909 alloy part is ring-shaped with an outer diameter of 600mm, an inner diameter of 500mm, and a height of 70mm. The tangential sampling is performed with a sampling size of Φ8mm. The condition before brazing is standard short-time double aging 2. The mechanical properties are shown in Table 10 below.

[0120] Table 10

[0121] Test temperature / ℃ Tensile strength / MPa Standard deviation / MPa room temperature 1225、1232、1238、1228、1214、1230 7.3 650 999、998、1008、1010、1002、1000 6.8 Test temperature / ℃ Yield strength / MPa Standard deviation / MPa room temperature 945、968、958、967、950、983 7.9 650 813、775、800、810、795、789 12.8 Test temperature / ℃ Elongation / % Standard deviation / % room temperature 14.2、15.5、14.5、14.8、14.8、11.9 1.1 650 17.5、18.2、19.2、18.8、20.1、24 2.1 Test temperature / ℃ Post-fracture shrinkage rate / % Standard deviation / % room temperature 29、30、31、34、37、36 3.0 650 32、35、36、34、37、35 1.6 Test temperature / ℃ Hardness / HB Standard deviation / HB room temperature 368.1、370.1、373.4、368.7、362.5、368.3 3.2 ;

[0122] S2. Vacuuming: Place the GH2909 alloy parts (cleaned from surface S1) in a vacuum brazing furnace and evacuate to a pressure not exceeding 10. -3 Pa;

[0123] S3. Vacuum Brazing Heat Treatment: The vacuum brazing furnace is heated to perform vacuum brazing heat treatment on the GH2909 alloy parts with clean S1 surfaces. The vacuum brazing heat treatment temperature is 1040℃, and the holding time is 10 min. The temperature is then increased to 550℃ at a rate of 15℃ / min and held for 10 min. The temperature is then increased to 940℃ at a rate of 20℃ / min and held for 10 min. Finally, the temperature is increased to 1040℃ at a rate of 10℃ / min. After brazing, the parts are cooled in the furnace at a cooling rate of 3℃ / min. The parts are cooled to 80℃ and then air-cooled to room temperature at a cooling rate of 70℃ / min to obtain the GH2909 alloy parts after vacuum brazing treatment.

[0124] S4. First aging treatment: The GH2909 alloy parts after S3 vacuum brazing heat treatment are subjected to a first aging treatment at a temperature of 620℃ for 8.5 hours. The heating rate is 15℃ / min, and the air cooling rate is 70℃ / min. After air cooling, GH2909 alloy parts with improved room temperature strength and stability are obtained.

[0125] In this embodiment, the GH2909 alloy component is ring-shaped with an outer diameter of 600mm, an inner diameter of 500mm, and a height of 70mm. The sample is taken tangentially with a sample size of Φ8. After vacuum brazing and one aging process, the mechanical properties are shown in Table 11 below.

[0126] Table 11

[0127] Test temperature / ℃ Tensile strength / MPa Standard deviation / MPa room temperature 1372、1378、1383、1388、1375、1380 5.8 650 1005、1015、1020、1008、1002、1016 6.9 Test temperature / ℃ Yield strength / MPa Standard deviation / MPa room temperature 1038、1035、1037、1042、1036、1040 2.5 650 825、822、828、824、826、821 2.6 Test temperature / ℃ Elongation / % Standard deviation / % room temperature 18.5、19.8、19.2、20.4、19.1、18.9 0.7 650 18.8、19.2、21.5、22.8、18.2、16.2 2.3 Test temperature / ℃ Post-fracture shrinkage rate / % Standard deviation / % room temperature 35、33、32、33、35、34 1.2 650 36、39、41、35、38、37 2.1 Test temperature / ℃ Hardness / HB Standard deviation / HB room temperature 379.2、381.8、376.4、377.5、380.9、378.5 2.0 ;

[0128] The microstructure of the GH2909 alloy component in this embodiment, after vacuum brazing and one aging process, consists of 80.05% γ solid solution, 13.50% γ′ phase, 4.48% Laves phase, and 1.97% ε phase (γ solid solution is generally not studied, and its shape and size are not fixed). Among them, the γ′ phase is shaped as small spheres or cubic, with an average size of 18.72 nm; the Laves phase is shaped as spheres or short rods, with an average major axis length of 1.78 μm and an average minor axis length of 0.81 μm; and the ε phase is shaped as needles with an average length of 1.52 μm.

[0129] Example 5

[0130] A vacuum brazing and heat treatment process for a GH2909 alloy component, wherein the GH2909 alloy used is a ring with an outer diameter of 400 mm, an inner diameter of 300 mm, and a height of 50 mm. The elemental composition by mass percentage is as follows: C 0.01%, Si 0.40%, Co 13.48%, Ni 38.06%, Ti 1.64%, Nb 4.88%, Al 0.031%, Mo 0.04%, with the balance being Fe and unavoidable impurities. The vacuum brazing and heat treatment process for the GH2909 alloy component is as follows:

[0131] S1. Surface Pretreatment: The surface of the GH2909 alloy part is pretreated to remove the oxide layer or oil stains. Finally, it is cleaned and dried to obtain a clean GH2909 alloy part. The GH2909 alloy part is ring-shaped with an outer diameter of 400mm, an inner diameter of 300mm, and a height of 50mm. The tangential sampling is performed with a sampling size of Φ8mm. The condition before brazing is standard short-time double aging 2. The mechanical properties are shown in Table 12 below.

[0132] Table 12

[0133]

[0134]

[0135] S2. Vacuuming: Place the GH2909 alloy parts (cleaned from surface S1) in a vacuum brazing furnace and evacuate to a pressure not exceeding 10. -3 Pa;

[0136] S3. Vacuum Brazing Heat Treatment: The vacuum brazing furnace is heated to perform vacuum brazing heat treatment on the GH2909 alloy parts with clean S1 surfaces. The temperature of the vacuum brazing heat treatment is 1000℃, and it is held for 30 minutes. The temperature is then increased to 620℃ at a rate of 15℃ / min and held for 10 minutes. The temperature is then increased to 910℃ at a rate of 20℃ / min and held for 10 minutes. Finally, the temperature is increased to 1000℃ at a rate of 10℃ / min. After brazing, the parts are cooled in the furnace at a rate of 3℃ / min until they reach 80℃. They are then removed and air-cooled to room temperature at a rate of 70℃ / min to obtain the GH2909 alloy parts after vacuum brazing heat treatment.

[0137] S4. First aging treatment: The GH2909 alloy parts after S3 vacuum brazing heat treatment are subjected to a first aging treatment at a temperature of 625℃ for 8.5 hours. The heating rate is 20℃ / min, and the air cooling rate is 70℃ / min. After air cooling, GH2909 alloy parts with improved room temperature strength and stability are obtained.

[0138] In this embodiment, the GH2909 alloy component is ring-shaped with an outer diameter of 400mm, an inner diameter of 300mm, and a height of 50mm. The sample is taken tangentially with a diameter of Φ8. After vacuum brazing and one aging process, the mechanical properties are shown in Table 13 below.

[0139] Table 13

[0140]

[0141]

[0142] The microstructure of the GH2909 alloy component in this embodiment, after vacuum brazing and one aging process, consists of 79.13% γ solid solution, 14.75% γ′ phase, 4.76% Laves phase, and 1.36% ε phase (γ solid solution is generally not studied, and its shape and size are not fixed). Among them, the γ′ phase is shaped as small spheres or cubic, with an average size of 18.88 nm; the Laves phase is shaped as spheres or short rods, with an average major axis length of 1.67 μm and an average minor axis length of 0.93 μm; and the ε phase is shaped as needles with an average length of 1.71 μm.

[0143] It should be understood that the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. Additionally, the character " / " in this article generally indicates an "or" relationship between the preceding and following related objects, but it can also represent an "and / or" relationship. Please refer to the context for a more accurate understanding.

[0144] In this invention, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of a single item or a plurality of items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be a single item or multiple items.

[0145] It should be understood that, in various embodiments of the present invention, the order of the above-mentioned process numbers does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0146] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A vacuum brazing and heat treatment process for GH2909 alloy components, characterized in that, The vacuum brazing and heat treatment process for the GH2909 alloy component is as follows: S1. Surface pretreatment: The surface of the GH2909 alloy parts is pretreated. The pretreatment includes removing the surface oxide layer or oil stains, and finally cleaning and drying to obtain clean GH2909 alloy parts. S2, Vacuuming: Place the GH2909 alloy parts with cleaned S1 surfaces in a vacuum brazing furnace and evacuate them; S3. Vacuum Brazing Heat Treatment: The vacuum brazing furnace is heated to perform vacuum brazing heat treatment on the GH2909 alloy parts with clean S1 surfaces. The temperature of the vacuum brazing heat treatment is 1000-1040℃, and the holding time is 10-30 min. The temperature needs to be increased to 550-650℃ at a rate of 10-15℃ / min and held for 10-20 min, then increased to 880-940℃ at a rate of 15-20℃ / min and held for 15-30 min, and finally increased to 1000-1040℃ at a brazing holding temperature at a rate of 5-10℃ / min. After that, the furnace is cooled, and then the parts are air-cooled to obtain the GH2909 alloy parts after vacuum brazing heat treatment. S4. First aging treatment: The GH2909 alloy parts after S2 vacuum brazing heat treatment are subjected to a first aging treatment. The temperature of the first aging treatment is 620±10℃, the holding time is 8±0.5h, the heating rate is 10-30℃ / min, and after air cooling, GH2909 alloy parts with improved room temperature strength and stability are obtained.

2. The vacuum brazing and heat treatment process for the GH2909 alloy component according to claim 1, characterized in that, The GH2909 alloy components in S1 are in bar shape, with dimensions of α150mm, α200mm, or α220mm, and are treated with standard double-aging heat treatment 2 (845℃×(4±0.5)h / FC→620℃×(4±0.5)h / AC); the room temperature tensile strength is 1190-1250MPa, with a standard deviation of 18-29MPa; the room temperature yield strength is 930-960MPa, with a standard deviation of 9-17MPa; the room temperature elongation is 13.7-17.8%, with a standard deviation of 0.9-1.5%; the room temperature cross-section... Shrinkage rate is 22-33%, with a standard deviation of 3.9-5.8%; room temperature hardness is 350-365 HB, with a standard deviation of 5-11 HB; tensile strength at 650℃ is 860-970 MPa, with a standard deviation of 19-31 MPa; yield strength at 650℃ is 715-800 MPa, with a standard deviation of 25-43 MPa; elongation at 650℃ is 12.5-20.4%, with a standard deviation of 2.3-6.7%; reduction of area at 650℃ is 26.0-40.5%, with a standard deviation of 4.5-8.9%.

3. The vacuum brazing and heat treatment process for GH2909 alloy components according to claim 1, characterized in that, The GH2909 alloy component in S1 is ring-shaped, with an outer diameter of 400-600 mm, an inner diameter of 300-500 mm, and a height of 70-90 mm. It is sampled tangentially and has undergone standard double-aging heat treatment 2 (845℃×(4±0.5)h / FC→620℃×(4±0.5)h / AC). Its room temperature tensile strength is 1200-1240 MPa, with a standard deviation of 15-27 MPa; its room temperature yield strength is 910-970 MPa, with a standard deviation of 20-45 MPa; and its room temperature elongation is 14.0-18.8%, with a standard deviation of 1.2-2. 0.3%; room temperature reduction of area is 24-37%, with a standard deviation of 3.6-5.9%; room temperature hardness is 350-365 HB, with a standard deviation of 6-11 HB; tensile strength at 650℃ is 930-970 MPa, with a standard deviation of 20-31 MPa; yield strength at 650℃ is 770-810 MPa, with a standard deviation of 25-43 MPa; elongation at 650℃ is 12.5-29.4%, with a standard deviation of 3.8-9.7%; reduction of area at 650℃ is 26.0-44.5%, with a standard deviation of 6.7-10.9%.

4. The vacuum brazing and heat treatment process for the GH2909 alloy component according to claim 1, characterized in that, The GH2909 alloy component in S1 is a square billet with dimensions of 90mm × 90mm × 90mm. It undergoes a standard double-aging heat treatment (845℃ × (4±0.5)h / FC → 620℃ × (4±0.5)h / AC). Its room temperature tensile strength is 1200-1230MPa, with a standard deviation of 15-28MPa; its room temperature yield strength is 890-945MPa, with a standard deviation of 19-35MPa; its room temperature elongation is 14.7-18.2%, with a standard deviation of 0.7-2.1%; and its room temperature reduction of area is [not specified]. The elongation at 650℃ is 26-37%, with a standard deviation of 2.7-5.9%; the room temperature hardness is 360-365 HB, with a standard deviation of 2-7 HB; the tensile strength at 650℃ is 935-980 MPa, with a standard deviation of 15-25 MPa; the yield strength at 650℃ is 784-820 MPa, with a standard deviation of 20-40 MPa; the elongation at 650℃ is 15.5-29.4%, with a standard deviation of 3.8-9.3%; and the reduction of area at 650℃ is 27.0-47.5%, with a standard deviation of 6.7-11.9%.

5. The vacuum brazing and heat treatment process for the GH2909 alloy component according to claim 1, characterized in that, In S2, vacuuming is performed until the pressure does not exceed 10. -3 Pa.

6. The vacuum brazing and heat treatment process for the GH2909 alloy component according to claim 1, characterized in that, In S3, the furnace is cooled along with the furnace at a rate of 3-8℃ / min. After cooling to below 80℃, the furnace is directly removed from the furnace. The rate of air cooling is 50-80℃ / min.

7. The vacuum brazing and heat treatment process for GH2909 alloy components according to claim 1, characterized in that, Remove the contents of S4 and air-cool them to room temperature at a rate of 50-80℃ / min.

8. The vacuum brazing and heat treatment process for GH2909 alloy components according to claim 2, characterized in that, S3 is in bar shape with dimensions of α150mm, α200mm, or α220mm, and is treated by vacuum brazing followed by a single aging process ((1000-1040)℃×(15-30)min / FC + 620℃×(8±0.5)h / AC); its room temperature tensile strength is 1350-1380MPa with a standard deviation of 10-17MPa; its room temperature yield strength is 1020-1050MPa with a standard deviation of 9-14MPa; its room temperature elongation is 17.9-23.2% with a standard deviation of 0.8-1.7%; and its room temperature cross-sectional area... Shrinkage rate is 27-39%, with a standard deviation of 2.9-4.8%; room temperature hardness is 370-385 HB, with a standard deviation of 3-8 HB; tensile strength at 650℃ is 1005-1025 MPa, with a standard deviation of 12-26 MPa; yield strength at 650℃ is 820-870 MPa, with a standard deviation of 25-33 MPa; elongation at 650℃ is 11.5-21.4%, with a standard deviation of 2.3-5.7%; reduction of area at 650℃ is 35.0-40.5%, with a standard deviation of 2.7-4.9%.

9. The vacuum brazing and heat treatment process for the GH2909 alloy component according to claim 3, characterized in that, S3 is annular in shape, with an outer diameter of 400-600 mm, an inner diameter of 300-500 mm, and a height of 70-90 mm. Sampling is performed tangentially, and the treatment state is vacuum brazing + one aging ((1000-1040)℃×(15-30)min / FC + 620℃×(8±0.5)h / AC). The room temperature tensile strength is 1340-1370 MPa, with a standard deviation of 11-15 MPa; the room temperature yield strength is 1025-1060 MPa, with a standard deviation of 10-14 MPa; and the room temperature elongation is 18.8-24.5%, with a standard deviation of 0.7- 1.4%; room temperature reduction of area is 30-39%, standard deviation is 2.7-4.2%; room temperature hardness is 370-385 HB, standard deviation is 3-9 HB; tensile strength at 650℃ is 1000-1020 MPa, standard deviation is 12-20 MPa; yield strength at 650℃ is 830-870 MPa, standard deviation is 20-30 MPa; elongation at 650℃ is 11.5-20.4%, standard deviation is 3.7-5.1%; reduction of area at 650℃ is 35.0-41.5%, standard deviation is 2.7-3.8%.

10. The vacuum brazing and heat treatment process for the GH2909 alloy component according to claim 4, characterized in that, S3 is a square billet with dimensions of 90mm × 90mm × 90mm, treated with standard double-aging heat treatment 2 (845℃ × (4±0.5)h / FC → 620℃ × (4±0.5)h / AC); its room temperature tensile strength is 1200-1230MPa, with a standard deviation of 15-28MPa; its room temperature yield strength is 890-945MPa, with a standard deviation of 19-35MPa; its room temperature elongation is 14.7-18.2%, with a standard deviation of 0.7-2.1%; and its room temperature reduction of area is 26-3... 7%, with a standard deviation of 2.7-5.9%; room temperature hardness is 360-365 HB, with a standard deviation of 2-7 HB; tensile strength at 650℃ is 935-980 MPa, with a standard deviation of 15-25 MPa; yield strength at 650℃ is 784-820 MPa, with a standard deviation of 20-40 MPa; elongation at 650℃ is 15.5-29.4%, with a standard deviation of 3.8-9.3%; reduction of area at 650℃ is 27.0-47.5%, with a standard deviation of 6.7-11.9%.

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