Effective refining method for multiphase structure of weldable Ni3Al-based alloy
Through laser remelting treatment and high-temperature aging treatment, the multiphase structure of the weldable Ni3Al base alloy is refined, which solves the problem of weakening of high-temperature mechanical properties caused by large-size β phase, and achieves the optimization of the high-temperature mechanical properties of the alloy.
Patent Information
- Application Number
- CN202411810335.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-10
- Publication Date
- 2025-03-18
AI Technical Summary
The introduction of large-size β phases in solderable Ni3Al base alloys has led to weakening of its high-temperature mechanical properties, and traditional heat treatment methods cannot effectively refine the β phase.
The multiphase structure of the weldable Ni3Al base alloy is refined by laser remelting treatment, and thermal stress is eliminated through high-temperature aging treatment, and finally furnace-cooled treatment is carried out to obtain excellent high-temperature mechanical properties.
The beta phase in the alloy is effectively refined, its high-temperature mechanical properties are improved, and its performance requirements in high-end manufacturing fields such as aerospace and automobile manufacturing.
Smart Images
Figure CN119640180A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of nickel-based multiphase alloy structure control, in particular to a weldable Ni 3 An effective refinement method for multiphase structure of Al-based alloys. Background Art
[0002] Ni 3 Al-based alloys have a higher volume fraction of γ′ phase (generally above 80 vol.%) than traditional nickel-based high-temperature alloys, and have good high-temperature mechanical properties. At the same time, they do not contain precious alloying elements such as rhenium (Re) and ruthenium (Ru), and the alloy density is lower (generally between 7.5 and 8.0 g / cm 3 The production cost is also greatly reduced; and it has excellent high temperature oxidation resistance / corrosion resistance and other characteristics. At present, it has been widely used in aerospace, automobile and steel industries. At present, its further promotion and application is still limited by Ni 3 The general unweldability of Al-based alloys.
[0003] At present, the new type of weldable Ni 3 Al-based alloys, due to the addition of Fe and Cr components, the introduction of a large-sized β phase with a high volume fraction (19.4 vol.%) in the alloy multiphase structure makes it comparable to other Ni 3 Compared with Al-based alloys, it has good high-temperature oxidation resistance and corrosion resistance while being weldable. It has been successfully used as a material for aircraft engine tail pipe nozzles.
[0004] However, the introduction of large-sized β phase improves weldability and also leads to the 3 The high temperature mechanical properties of Al-based alloys are greatly weakened, and traditional heat treatment methods cannot effectively refine the weldable Ni 3 Large-sized β phase in Al-based alloys. Therefore, how to effectively refine the multiphase structure (especially the large-sized β phase) to solve the problem of weldable Ni 3 The problem of weakened high temperature mechanical properties of Al-based alloys has been the main problem in recent years. 3 Key frontier research issues in Al-based alloys. Summary of the invention
[0005] The object of the present invention is to provide a weldable Ni 3 An effective method for refining the multiphase structure of Al-based alloys is used to weld Ni 3 The Al-based alloy is laser remelted to refine its structure to a greater extent; the weldable Ni 3The Al-based alloy is placed in a high-temperature heat treatment furnace for high-temperature aging treatment to eliminate the thermal stress after laser remelting; the weldable Ni 3 The Al-based alloy is furnace-cooled to obtain a weldable Ni-based alloy with effectively refined multiphase structure and excellent high-temperature mechanical properties. 3 Al-based alloy.
[0006] To achieve the above object, the present invention provides a weldable Ni 3 The effective refinement method of multiphase structure of Al-based alloy comprises the following steps:
[0007] S1, will be weldable Ni 3 After the Al-based alloy is laser remelted, the remelted layer is cut to obtain weldable Ni 3 Al-based alloy remelting layer;
[0008] S2, the weldable Ni obtained in S1 3 The Al-based alloy remelting layer is subjected to high temperature aging treatment;
[0009] S3, after eliminating the thermal stress obtained in S2, Ni can be welded 3 The Al-based alloy cools down with the furnace;
[0010] S4, obtain weldable Ni with effective multiphase structure refinement and excellent high temperature mechanical properties 3 Al-based alloy.
[0011] Preferably, in step S1, the laser power of laser remelting is 1500-4500 W, and the scanning rate is 5-10 mm / s.
[0012] Preferably, in step S1, the weldable Ni 3 The Al-based alloy remelted layer is cleaned by ultrasonic wave and blown dry.
[0013] S2-1, Ni 3 The Al-based alloy remelted layer is placed in a ceramic crucible;
[0014] S2-2, use crucible tongs to remove the solderable Ni 3 The ceramic crucible of the remelted layer of the Al-based alloy is placed in a high-temperature heat treatment furnace for high-temperature aging treatment.
[0015] Preferably, the temperature of the high temperature heat treatment furnace is 900-1020° C., and the heating and insulation time is 500 h.
[0016] The invention discloses a weldable Ni 3 The effective refinement method of multiphase structure of Al-based alloy has the following beneficial effects:
[0017] 1. The present invention is to weld Ni3 The Al-based alloy is laser remelted to refine its structure to a greater extent, making it possible to weld Ni 3 The surface metal of the Al-based alloy melts rapidly under the action of the heat source and then cools and solidifies. The rapid cooling process increases the metal's supercooling, thereby increasing the number of nuclei. The increase in the number of nuclei means that the growth space of the grains is limited, which in turn inhibits the growth of the grains and promotes the formation of fine-grained structure. Refined grains can improve the strength, toughness and wear resistance of the material, and refined organizational phases can improve the material's processing performance, reduce cutting forces and increase cutting speeds, which is of great significance for improving production efficiency and reducing production costs. At the same time, it expands the application range of the material to meet the performance requirements of the material in high-end manufacturing fields such as aerospace, automobile manufacturing, etc.
[0018] 2. The present invention is to remelt the weldable Ni 3 The Al-based alloy is heat treated to eliminate the thermal stress of the alloy with uneven internal force after rapid dissolution and rapid cooling, which greatly reduces the thermal stress generated inside the material after laser remelting.
[0019] 3. The present invention reduces the size of the β phase, makes its distribution uniform, and keeps its volume fraction unchanged.
[0020] 4. For weldable Ni 3 For Al-based alloys, the β phase has relatively strict size requirements as a weldable phase. If the size of the β phase is too large, its high-temperature mechanical properties may decrease, and if the size is too small, the alloy may lose weldability and stability. Through research, the present invention finds that long-term aging treatment of 500 hours can make the β phase grow to the most suitable size, thereby ensuring the comprehensive mechanical properties of the alloy.
[0021] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 A weldable Ni 3 Flow chart of the effective refinement method of multiphase structure of Al-based alloys;
[0023] Figure 2 The weldable Ni in the cast state in the specific embodiment 1 3 SEM image of Al-based alloy;
[0024] Figure 3 The weldable Ni in the specific embodiments 1 to 4 is subjected to furnace cooling and high temperature aging at different temperatures. 3 SEM low magnification morphology of Al-based alloy, where (a) is a weldable Ni alloy subjected to high temperature aging treatment at 900°C-500h in specific embodiment 1 3SEM low magnification morphology of Al-based alloy, (b) is a weldable Ni alloy subjected to high temperature aging treatment at 940℃-500h in specific embodiment 2 3 SEM low magnification morphology of Al-based alloy, (c) is the weldable Ni after high temperature aging treatment at 980℃-500h in specific embodiment 3 3 SEM low magnification morphology of Al-based alloy, (d) is a weldable Ni alloy subjected to high temperature aging treatment at 1020℃-500h in specific embodiment 4 3 SEM low-magnification morphology of Al-based alloy. DETAILED DESCRIPTION
[0025] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.
[0026] Unless otherwise defined, technical or scientific terms used in the present invention shall have the common meanings understood by one having ordinary skills in the field to which the present invention belongs.
[0027] In addition, it should be understood that although this specification is described according to the implementation modes, not every implementation mode includes only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation modes that can be understood by those skilled in the art. These other implementation modes are also covered within the protection scope of the present invention.
[0028] As stated in the attached Figure 1 As shown in the flow chart, the present invention uses a SMATLas Series5M-6000W (China) fiber laser generator to weld Ni 3 The Al-based alloy is laser remelted to refine its structure to a greater extent. Due to the characteristics of rapid melting and rapid cooling of laser remelting technology, the internal force of the alloy is uneven, which in turn generates thermal stress. 3 The Al-based alloy is placed in a high-temperature heat treatment furnace for high-temperature aging treatment; the thermal stress after laser remelting is eliminated; the weldable Ni 3 The Al-based alloy is furnace-cooled; finally, a weldable Ni alloy with effectively refined multiphase structure and excellent high-temperature mechanical properties is obtained. 3 Al-based alloy.
[0029] The specific implementation steps are as follows:
[0030] S1 will select the weldable Ni 3 Laser remelting of Al-based alloys
[0031] S2, the obtained weldable Ni 3The Al-based alloy remelting layer is placed in a high-temperature heat treatment furnace for high-temperature aging treatment;
[0032] S3, the Ni obtained in step S21 is welded after eliminating thermal stress 3 Al-based alloy is cooled in the furnace
[0033] S4, obtain weldable Ni with effective multiphase structure refinement and excellent high temperature mechanical properties 3 Al-based alloy.
[0034] Furthermore, the laser remelting process in step S1 includes:
[0035] S11. The laser remelting process uses a 5M-6000W fiber laser generator with a laser power of 1500 to 4500W and a scanning rate of 5 to 10 mm / s;
[0036] S12, remelt the weldable Ni 3 The Al-based alloy is placed in an electric spark wire cutting machine for cutting, and the remelted layer is cut off and cleaned and dried by an ultrasonic cleaning device.
[0037] Furthermore, the specific process of heat treatment in step S2 is as follows:
[0038] S21, will be weldable Ni 3 The remelted layer of the Al-based alloy is placed in a ceramic crucible;
[0039] S22, use crucible tongs to remove the solderable Ni 3 The ceramic crucible of the remelting layer of the Al-based alloy is placed in a high-temperature heat treatment furnace, and corresponding heat treatment parameters are set, the temperature is 900-1020° C., and the heating and holding time is 500 h.
[0040] The following is a description of a weldable Ni 3 The method of effectively refining the multiphase structure of Al-based alloys is further described:
[0041] Reference to "embodiment" herein means that the specific features, structures or characteristics described in conjunction with the embodiment may be included in at least one embodiment of the present application. The term "embodiment" appearing in various places in the specification does not necessarily refer to the same embodiment, nor does it particularly limit its independence or association with other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, the various technical features mentioned in the embodiments can be combined in any way to form a corresponding implementable technical solution.
[0042] Unless otherwise defined, the technical terms used in this document have the same meanings as those generally understood by those skilled in the art to which this application belongs; the use of relevant terms in this document is only for describing specific embodiments and is not intended to limit this application.
[0043] Unless otherwise specified in the present invention, the reagents, instruments, and equipment used are those commonly used by technicians in this field. Specific embodiment one:
[0045] S1. Select the weldable Ni 3 The Al-based alloy was laser remelted.
[0046] S11. The laser remelting process uses a 5M-6000W fiber laser generator with a laser power of 4500W and a scanning rate of 10mm / s.
[0047] S12, remelt the weldable Ni 3 The Al-based alloy is placed in an electric spark wire cutting machine for cutting, and the remelted layer is cut off and cleaned and dried by an ultrasonic cleaning device.
[0048] Cast weldable Ni 3 SEM images of Al-based alloys are shown in Figure 2 As shown, the weldable Ni after remelting 3 Al-based alloys simultaneously have γ′+γ dendrites, γ′-envelope structure and interdendritic β phase.
[0049] S2, the obtained weldable Ni 3 The Al-based alloy remelted layer is placed in a high-temperature heat treatment furnace for high-temperature aging treatment.
[0050] S21, will be weldable Ni 3 The remelted layer of the Al-based alloy is placed in a ceramic crucible.
[0051] S22, use crucible tongs to weld Ni 3 The ceramic crucible of the remelted layer of the Al-based alloy is placed in a high-temperature heat treatment furnace for high-temperature aging treatment at 900°C / 500h to eliminate the thermal stress generated by the remelting.
[0052] S3, the obtained weldable Ni after eliminating thermal stress 3 The Al-based alloy remelted layer is furnace cooled.
[0053] S4, obtain weldable Ni with effective multiphase structure refinement and excellent high temperature mechanical properties 3 Al-based alloy.
[0054] The weldable Ni 3 The multiphase microstructure of Al-based alloys is shown in Figure 3 (a) shown. Specific embodiment 2
[0056] S1. Select the weldable Ni 3 The Al-based alloy was laser remelted.
[0057] S11. The laser remelting process uses a 5M-6000W fiber laser generator with a laser power of 4000W and a scanning rate of 10mm / s.
[0058] S12, remelt the weldable Ni 3 The Al-based alloy is placed in an electric spark wire cutting machine for cutting, and the remelted layer is cut off and cleaned and dried by an ultrasonic cleaning device.
[0059] S2, the obtained weldable Ni 3 The Al-based alloy remelted layer is placed in a high-temperature heat treatment furnace for high-temperature aging treatment.
[0060] S21, will be weldable Ni 3 The remelted layer of the Al-based alloy is placed in a ceramic crucible.
[0061] S22, use crucible tongs to weld Ni 3 The ceramic crucible of the remelted layer of the Al-based alloy is placed in a high-temperature heat treatment furnace for high-temperature aging treatment at 940°C-500h to eliminate the thermal stress generated by the remelting.
[0062] S3, the obtained weldable Ni after eliminating thermal stress 3 The Al-based alloy remelted layer is furnace cooled.
[0063] S4, obtain weldable Ni with effective multiphase structure refinement and excellent high temperature mechanical properties 3 Al-based alloy.
[0064] The weldable Ni 3 The multiphase microstructure of Al-based alloys is shown in Figure 3 (b) as shown. Specific embodiment three
[0066] S1. Select the weldable Ni 3 The Al-based alloy was laser remelted.
[0067] S11. The laser remelting process uses a 5M-6000W fiber laser generator with a laser power of 3500W and a scanning rate of 5mm / s.
[0068] S12, remelt the weldable Ni 3 The Al-based alloy is placed in an electric spark wire cutting machine for cutting, and the remelted layer is cut off and cleaned and dried by an ultrasonic cleaning device.
[0069] S2, the obtained weldable Ni 3 The Al-based alloy remelted layer is placed in a high-temperature heat treatment furnace for high-temperature aging treatment.
[0070] S21, will be weldable Ni 3 The remelted layer of the Al-based alloy is placed in a ceramic crucible.
[0071] S22, use crucible tongs to weld Ni 3 The ceramic crucible of the remelted layer of the Al-based alloy is placed in a high-temperature heat treatment furnace for high-temperature aging treatment at 980°C-500h to eliminate the thermal stress generated by the remelting.
[0072] S3, the obtained weldable Ni after eliminating thermal stress 3 The Al-based alloy remelted layer is furnace cooled.
[0073] S4, obtain weldable Ni with effective multiphase structure refinement and excellent high temperature mechanical properties 3 Al-based alloy.
[0074] The weldable Ni 3 The multiphase microstructure of Al-based alloys is shown in Figure 3 (c) as shown. Specific embodiment 4
[0076] S1. Select the weldable Ni 3 The Al-based alloy was laser remelted.
[0077] S11. The laser remelting process uses a 5M-6000W fiber laser generator with a laser power of 4000W and a scanning rate of 10mm / s.
[0078] S12, remelt the weldable Ni 3 The Al-based alloy is placed in an electric spark wire cutting machine for cutting, and the remelted layer is cut off and cleaned and dried by an ultrasonic cleaning device.
[0079] S2, the obtained weldable Ni 3 The Al-based alloy remelted layer is placed in a high-temperature heat treatment furnace for high-temperature aging treatment.
[0080] S21, will be weldable Ni 3 The remelted layer of the Al-based alloy is placed in a ceramic crucible.
[0081] S22, use crucible tongs to weld Ni 3 The ceramic crucible of the remelted layer of the Al-based alloy is placed in a high-temperature heat treatment furnace for high-temperature aging treatment at 1020°C-500h to eliminate the thermal stress generated by the remelting.
[0082] S3, the Ni after eliminating thermal stress 3 The Al-based alloy remelted layer is furnace cooled.
[0083] S4, obtain weldable Ni with effective multiphase structure refinement and excellent high temperature mechanical properties 3 Al-based alloy.
[0084] The weldable Ni 3 The multiphase microstructure of Al-based alloys is shown in Figure 3 (d) as shown.
[0085] The weldable Ni 3 The multiphase microstructure of Al-based alloys is shown in Figure 3 As shown, through measurement and calculation, it can be obtained that the weldable Ni 3 After Al-based alloys were aged in furnaces at different temperatures (900-1020℃) for 500h, the microstructures of the β phase and γ′+γ phases in the multiphase structure were significantly different. With the increase of the high-temperature aging treatment temperature, the size of the β phase increased significantly, and the average size of a single β phase was 2.1μm. 2 、7.5μm 2 、9.4μm 2 and 18.2 μm 2 , while the distribution density of β phase is not much different. The analysis shows that after the alloy is subjected to high temperature aging treatment at different temperatures, the size of β phase and γ′+γ two-phase structure increases with the increase of aging treatment temperature, and the distribution density of β phase remains unchanged. During the high temperature aging process of the alloy, the β phase and γ′+γ two-phase structure dissolve and grow together, accompanied by the growth of γ′(Ni 3 Al)←→β(NiAl)+γ(Ni) phase transition reaction.
[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.
Claims
1. An effective method for refining the multiphase structure of a weldable Ni3Al-based alloy, characterized in that: The following steps are involved: S1, after laser remelting the weldable Ni3Al-based alloy, cutting the remelted layer to obtain a weldable Ni3Al-based alloy remelted layer; S2, subjecting the weldable Ni3Al-based alloy remelting layer obtained in S1 to high temperature aging treatment; S3, cooling the weldable Ni3Al-based alloy remelting layer obtained in S2 after eliminating thermal stress along with the furnace; S4. A weldable Ni3Al-based alloy with effectively refined multiphase structure and excellent high-temperature mechanical properties is obtained.
2. The method for effectively refining the multiphase structure of a weldable Ni3Al-based alloy according to claim 1, characterized in that: In step S1, the laser power of laser remelting is 1500-4500 W, the scanning rate is 5-10 mm / s, and the thickness of the Ni3Al-based alloy remelting layer is 1 mm.
3. The method for effectively refining the multiphase structure of a weldable Ni3Al-based alloy according to claim 1, characterized in that: In step S1, the cut is performed by an electric spark wire cutting machine, and the cut weldable Ni3Al-based alloy remelting layer is cleaned and dried by ultrasonic wave.
4. The method for effectively refining the multiphase structure of a weldable Ni3Al-based alloy according to claim 1, characterized in that: Step S2 specifically includes the following steps: S2-1, placing a weldable Ni3Al-based alloy remelting layer in a ceramic crucible; S2-2, using crucible tongs, place the ceramic crucible containing the remelted layer of the weldable Ni3Al-based alloy in step S2-1 in a high-temperature heat treatment furnace for high-temperature aging treatment.
5. The method for effectively refining the multiphase structure of a weldable Ni3Al-based alloy according to claim 4, characterized in that: The temperature of the high temperature heat treatment furnace is 900-1020°C, and the heating and insulation time is 500h.