A method for controlling b' / u2 complex phase in aluminum alloy and aluminum alloy

Abstract

The application provides a method for regulating B' / U2 composite phase in an aluminum alloy and the aluminum alloy, and comprises the following steps: solid solution treatment: heating the aluminum alloy to a solid solution temperature and keeping it for a certain time to form a supersaturated solid solution in the aluminum alloy; deformation treatment: compressively deforming the aluminum alloy to form a dislocation structure in the aluminum alloy; quenching treatment: rapidly quenching the deformed aluminum alloy to room temperature to retain the supersaturated solid solution and the dislocation structure in the aluminum alloy; and aging treatment: artificially aging the quenched aluminum alloy to induce the B' / U2 composite phase in the aluminum alloy to directionally precipitate along the dislocation structure. The application realizes the quantifiable regulation of the morphology, size and distribution of the dislocation-induced B' / U2 composite phase through the integrated process of solid solution-deformation-quenching-aging, effectively avoids the long-range disorder and mixed phase inclusion of the composite phase in the traditional process, improves the microstructure stability and macroscopic mechanical properties of the aluminum alloy, and enhances the strengthening effect, stress corrosion resistance and long-term service stability of the aluminum alloy.

Description

Technical Field

[0001] This invention relates to the field of metal material processing technology, specifically providing a method for controlling the B' / U2 composite phase in aluminum alloys and an aluminum alloy thereof. Background Technology

[0002] 6082 aluminum alloy, a typical Al-Mg-Si alloy, is a core material for aluminum alloy spacers in power transmission and distribution systems due to its excellent strength-to-weight ratio, weldability, and corrosion resistance. It is widely used in critical connections and support scenarios in power grid architecture. The service reliability of this type of spacer mainly stems from the dispersed nanoscale precipitates within the material. These precipitates effectively hinder dislocation movement, thereby strengthening the alloy and enabling it to withstand tensile and compressive loads and corrosive media erosion under complex operating conditions. Its resistance to stress corrosion is directly related to the hot working process and the microstructure during processing.

[0003] The generally accepted precipitation sequence for Al-Mg-Si alloys is as follows: supersaturated solid solution → atomic clusters / GP regions → β'' phase → metastable phases such as β' / B' / U1 / U2 phases → equilibrium β phase (Mg2Si phase). Among them, the acicular monoclinic β'' phase (Mg5Si6) is the main strengthening phase in the peak aging stage, with the most significant strengthening effect; while the β' phase (hexagonal structure Mg9Si5), B' phase (hexagonal structure Al3Mg9Si7), and U2 phase (orthorhombic structure Mg2Al2Si2) are mostly composite phases that precipitate in the over-aging stage, providing multiple possibilities for the control of alloy properties.

[0004] In traditional processes, the precipitation behavior of different types of Al-Mg-Si alloys (such as "normal β'' hardening type" and "normal β' hardening type") has inherent differences, resulting in large fluctuations in age hardening potential. The precipitated composite phases are mainly string-like, strip-like B' phases and some β' / B' / U2 phases. Not only is the precipitation amount insufficient, but it is also distributed in a discrete and mixed manner, which cannot form a uniform and dispersed strengthening system. Ultimately, this results in a significant decrease in the tensile load bearing capacity, compressive strength and stress corrosion resistance of aluminum alloys, making it difficult to meet the stringent requirements for material performance stability and reliability in power components and other applications. Summary of the Invention

[0005] The purpose of this invention is to solve the problem that the existing process for aging 6082 aluminum alloy results in insufficient precipitation of β' / B' / U2 phases, which are discrete and have inclusion distribution, leading to unsatisfactory strengthening effect on the aluminum alloy.

[0006] The objective of this invention is achieved through the following technical solution: This invention provides a method for controlling the B' / U2 composite phase in aluminum alloys, comprising: solution treatment: heating the aluminum alloy to the solution temperature and holding it at that temperature to form a supersaturated solid solution within the aluminum alloy; deformation treatment: compressing and deforming the aluminum alloy to form a dislocation structure within the aluminum alloy; quenching treatment: rapidly quenching the deformed aluminum alloy to room temperature to retain the supersaturated solid solution and dislocation structure within the aluminum alloy; and aging treatment: artificially aging the quenched aluminum alloy to induce the B' / U2 composite phase in the aluminum alloy to precipitate oriented along the dislocation structure.

[0007] Preferably, the heating rate of the solution treatment is 10℃ / s-15℃ / s, the solution temperature is 530℃-540℃, and the holding time is 10min-15min.

[0008] Preferably, in the deformation treatment step, the deformation amount of the aluminum alloy during compressive deformation is 45%-55%, and the strain rate is 0.1s. -1 -10s -1 .

[0009] Preferably, the dislocation density forming the dislocation structure during the deformation process is 6.2 × 10⁻⁶. 14 m -2 -9.8×10 14 m -2 The dislocation spacing is 20nm-50nm.

[0010] Preferably, in the deformation process, the aluminum alloy undergoes a single-stage unidirectional hot-press deformation at the solution treatment temperature.

[0011] Preferably, in the deformation process, the aluminum alloy undergoes multiple unidirectional hot-pressing deformations at a stepped temperature range of 430℃-535℃.

[0012] Preferably, the stepped temperatures are 430°C, 465°C, 500°C and 535°C.

[0013] Preferably, the aging temperature in the aging process is 175℃-185℃, and the aging time is 5h-7h.

[0014] Preferably, the aging temperature in the aging process is 180°C and the aging time is 6 hours.

[0015] Preferably, the control method is applicable to any one of the Mg / Si 6082 aluminum alloy system, Mg-rich aluminum alloy system, and balanced composition aluminum alloy system.

[0016] Preferably, in the aging treatment step, the B' / U2 composite phase is uniformly distributed in an X-shape in the easily deformable region of the aluminum alloy, with the B' phase size being 10nm-30nm, the U2 phase size being 5nm-15nm, and the B' / U2 composite phase number density being ≥1.5×10⁻⁶. 3 / μm 2 .

[0017] Based on the same inventive concept, the present invention also provides an aluminum alloy, which is processed by the aforementioned method for controlling the B' / U2 composite phase in the aluminum alloy.

[0018] Preferably, the aluminum alloy is used to manufacture electrical spacer bars.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention relates to a method for controlling the B' / U2 composite phase in aluminum alloys, comprising: solution treatment: heating the aluminum alloy to the solution temperature and holding it at that temperature to form a supersaturated solid solution within the aluminum alloy; deformation treatment: compressing and deforming the aluminum alloy to form a dislocation structure within the aluminum alloy; quenching treatment: rapidly quenching the deformed aluminum alloy to room temperature to retain the supersaturated solid solution and dislocation structure within the aluminum alloy; and aging treatment: artificially aging the quenched aluminum alloy to induce the directional precipitation of the B' / U2 composite phase along the dislocation structure. This invention achieves quantifiable control over the morphology, size, and distribution of the dislocation-induced B' / U2 composite phase through an integrated solution-deformation-quenching-aging process, effectively avoiding the long-range disorder and impurity phase inclusions of the composite phase in traditional processes. This improves the microstructure stability and macroscopic mechanical properties of the aluminum alloy, enhancing its strengthening effect, stress corrosion resistance, and long-term service stability. Attached Figure Description

[0020] Figure 1 This is a process flow diagram of the method for controlling the B' / U2 composite phase in aluminum alloys according to the present invention; Figure 2 This is a schematic diagram showing the location of the microstructure characterization of the compression deformation sample and the compression axial section after the aluminum alloy sample was subjected to the B' / U2 composite phase control method of the present invention. Figure 3 TEM images of the precipitated phases at LAGG and dislocation sites in the aluminum alloy sample prepared in Example 2; Figure 4 This is a schematic diagram and a physical comparison diagram of the unidirectional compression alloy specimen of the thermoforming simulation testing machine of the present invention. Figure 5 The true stress-true strain curve of the aluminum alloy sample prepared in Example 2 during a single uniaxial compression process; Figure 6The true stress-true strain curves of the aluminum alloy sample prepared in Example 3 under multiple uniaxial compression processes at stepped temperatures. Detailed Implementation

[0021] To enable those skilled in the art to better understand the technical solutions of the present invention, the preferred embodiments of the present invention are described below in conjunction with specific applications. Obviously, the described embodiments are merely a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0022] Unless otherwise specified, the experimental or testing methods described in the following examples are conventional methods; the reagents and materials described are obtained from conventional commercial sources or prepared using conventional methods, unless otherwise specified.

[0023] like Figure 1 As shown, this invention provides a method for controlling the B' / U2 composite phase in aluminum alloys, comprising: S1. Solution treatment: The aluminum alloy is heated to the solution temperature and held at that temperature to form a supersaturated solid solution within the aluminum alloy. S2. Deformation treatment: Compressing and deforming the aluminum alloy to form a dislocation structure inside the aluminum alloy; S3. Quenching treatment: The deformed aluminum alloy is rapidly quenched to room temperature to retain the supersaturated solid solution and dislocation structure in the aluminum alloy. S4. Aging treatment: Artificial aging is performed on the quenched aluminum alloy to induce the directional precipitation of the B' / U2 composite phase along the dislocation structure in the aluminum alloy.

[0024] Specifically, in step S1, aluminum alloy extruded bars in a free-processing state are selected, sampled radially and cut into cylinders, and then polished with sandpaper to eliminate surface defects and reduce frictional resistance. The aluminum alloy cylinders are heated to a solution temperature of 530℃-540℃ at a heating rate of 10℃ / s-15℃ / s and held at that temperature for 10min-15min.

[0025] In step S2, a thermoforming simulation testing machine is used to deform the aluminum alloy, controlling the compressive deformation of the aluminum alloy to be 45%-55% and the strain rate to be 0.1 s. -1 -10s -1 To achieve a dislocation density of 6.2 × 10¹ for the aluminum alloy to form a dislocation structure during the deformation process. 4 m - ²-9.8×10¹ 4 m - ², with a dislocation spacing of 20nm-50nm.

[0026] In a preferred embodiment, the aluminum alloy is subjected to single-stage unidirectional hot-pressing deformation at the solution treatment temperature.

[0027] In another preferred embodiment, the aluminum alloy is subjected to multiple unidirectional hot-pressing deformations within a temperature gradient range of 430℃ to 535℃. The temperature gradients are 430℃, 465℃, 500℃, and 535℃.

[0028] like Figure 4 As shown, during the hot pressing deformation process, Figure 4 (a) The aluminum alloy cylinder is mounted on the machine pressure head, and a mechanical sensor is arranged on the pressure head. Graphite sheets are attached to the end face of the aluminum alloy cylinder to reduce friction. Temperature is monitored by means of a K-type thermocouple. A unidirectional loading force is applied based on a thermoforming simulation test machine to control the strain rate and deformation. During the deformation process, the collected stress-displacement data is converted into true stress-true strain data.

[0029] In step S3, the compressed aluminum alloy cylinder is rapidly water-quenched to room temperature.

[0030] like Figure 4 As shown, Figure 4 (b) The quenching nozzle is directly aimed at the aluminum alloy cylinder to spray water.

[0031] In step S4, the artificial aging temperature is 175℃-185℃, and the aging time is 5h-7h.

[0032] After aging treatment, the B' / U2 composite phase is uniformly distributed in an X-shape in the easily deformable region of the aluminum alloy. The size of the B' phase is 10-30 nm, the size of the U2 phase is 5 nm-15 nm, and the number density of the B' / U2 composite phase is ≥1.5×10³ / μm².

[0033] It should be noted that this control method is applicable to any of the Mg / Si 6082 aluminum alloy system, Mg-rich aluminum alloy system, and balanced composition aluminum alloy system.

[0034] The present invention also provides an aluminum alloy, which is processed by the above-mentioned method for controlling the B' / U2 composite phase in aluminum alloy.

[0035] The aluminum alloy treated with the control method has a yield strength ≥302.1 MPa and a hardness ≥121.9 HV. This aluminum alloy is used to manufacture electrical spacer bars.

[0036] The 6082 aluminum alloys provided in the following embodiments are all processed using the above-mentioned method for controlling the B' / U2 composite phase in aluminum alloys. The only difference is the control parameters used in the embodiments.

[0037] Examples 1-3 and Comparative Examples 1-2 Examples 1-3 and Comparative Examples 1-2 all used 6082 aluminum alloy extruded bars in a free-processing state. Radial samples were taken and cut into cylindrical specimens with a diameter of 10 mm and a height of 15 mm. Table 1 is a comparison table of the control processes for the cylindrical aluminum alloy specimens in Examples 1-3 and Comparative Examples 1-2.

[0038] Table 1

[0039] It should be noted that in Example 3, the deformation treatment involved staged compression deformation at temperatures of 430℃, 465℃, 500℃, and 535℃, with strain rates of 0.1 s⁻¹ corresponding to each of these temperature steps. -1 1s -1 10s -1 1s -1 Comparative Example 1 was processed using conventional process parameters, while Comparative Example 2 used conventional process parameters but skipped the deformation process.

[0040] Test Results The samples prepared in Examples 1-3 were processed according to the process control in Table 1, and their performance and microstructure were analyzed using various characterization methods.

[0041] The low-magnification morphology of the microstructure was observed using an optical microscope. The distribution of the second phase and the grain orientation were analyzed using scanning electron microscopy and electron backscatter diffraction. The crystal structure, size and elemental distribution of the B' / U2 composite phase were characterized by transmission electron microscopy combined with energy dispersive spectroscopy. At the same time, the mechanical properties of the material were evaluated by hardness testing.

[0042] True stress-true strain curves were plotted at different temperatures, and the distribution of the second phase, grain orientation, and dislocation state were analyzed using microscopic characterization techniques to clarify the influence of deformation temperature on the rheological behavior of the material and the control of the composite phase.

[0043] Specifically, rapid quenching of 6082 aluminum alloy after compression deformation preserved the deformed microstructure. Although the rearrangement and consumption of dislocations during deformation slowed down the further increase in dislocation density, high strain rates (e.g., 10 s⁻¹) still contributed to the formation of the microstructure. - ¹) The deformed sample still maintained a high dislocation density after aging.

[0044] like Figure 2 As shown, where Figure 2 -a displays photographs of the overall sample and its axial cross-section of a uniaxially compressed and aged 6082 aluminum alloy sample. Figure 2-b displays the location and state distribution of microstructure characterization in different deformation regions of the sample under loading deformation. These different deformation regions include easily deformable region I, shear deformation region II, free deformation region III, and difficult-to-deform region IV. In the deformation regions, σ1 represents the X-axis stress, σ2 the Y-axis stress, and σ3 the Z-axis stress.

[0045] The easily deformable region I is under triaxial compressive stress, resulting in intense and uniform plastic deformation. This leads to a high-density, uniformly distributed distribution of dislocations and low-angle grain boundaries (LAGB), providing an optimal template for the directional nucleation of the B' / U2 composite phase. Consequently, the B' / U2 phase in this region exhibits a dispersed and ordered distribution with good size consistency (B' phase 10nm-30nm, U2 phase 5nm-15nm). Although the shear deformation region II and the difficult-to-deform region IV are under triaxial compressive stress, the former suffers from uneven dislocation distribution due to shearing, while the latter suffers from insufficient deformation due to friction. Both result in disordered nucleation and easy aggregation of the B' / U2 phase. In the free deformation region III, where σ1 is tensile stress, dislocations are prone to slip annihilation, leading to insufficient nucleation and scattered distribution of the B' / U2 phase. Therefore, selecting the easily deformable region I as the microstructure analysis sampling area (with the observation plane parallel to the compression direction) allows for precise capture of the core effect of dislocation-induced directional precipitation of the B' / U2 composite phase in this invention, establishing a unified benchmark for comparing the precision and performance of composite phase control among different samples.

[0046] like Figure 3 As shown, this illustrates the typical distribution morphology of dislocations within aluminum alloys, primarily consisting of low-angle grain boundaries and intragranular tangled dislocations. The formation of LAGB (Low-Angle Grain Boundary) is attributed to an increase in local orientation difference, while the dislocation tangling reflects the distribution of intragranular stress and the hindrance to slip. This defect structure greatly promotes atomic diffusion, further accelerating the precipitation of solute atoms during aging.

[0047] Specifically, in the microstructure after aging, in Figure 3 In (a), precipitates near dislocations and grain boundaries can be observed, mainly distributed in LAGB and at dislocations.

[0048] exist Figure 3 In (b), the second phase is typically distributed in a lamellar pattern, forming ordered or disordered precipitates at dislocations and LAGBs. The lamellar phase precipitated at LAGBs exhibits a disordered B' / U2 phase, which contributes significantly to the material's mechanical properties through the Orowan bypass mechanism.

[0049] exist Figure 3 In (c), regions II-III show a complex phase precipitated at dislocations, consisting of a β" phase and disordered TypeDis1 and TypeDis2 phases. The coexistence of these multiple precipitates indicates that high dislocation density and vacancy concentration effectively promote the simultaneous nucleation and growth of multiple precipitates.

[0050] like Figure 5 As shown in the true stress-true strain curves of the sample in Example 2, under all deformation conditions, the flow stress rises rapidly in the initial stage of deformation, exhibiting work hardening characteristics caused by dislocation accumulation induced by deformation. With increasing deformation, the flow stress reaches its peak and then enters a steady state, indicating that work hardening and softening interactions occur within the material, forming a high-temperature dynamic softening phenomenon. During this process, the dislocation density within the material continuously increases, and simultaneously, dislocations migrate, rearrange, and annihilate under dynamic softening, resulting in a decrease in true stress and a reduction in the slope of the flow stress curve. At the same deformation temperature, the higher the strain rate, the greater the peak and steady-state stress values ​​of the flow stress, exhibiting a significant strain rate hardening effect. This indicates that the material exhibits low dynamic softening and low dislocation consumption when deformed at high strain rates; conversely, the material exhibits high dynamic softening and high dislocation consumption when deformed at low strain rates. At the same strain rate, the higher the deformation temperature, the lower the peak and steady-state stress values ​​of the flow stress, indicating that increasing the deformation temperature can enhance the degree of dynamic softening during material deformation. When the deformation temperature is the solution temperature, the material exhibits the highest degree of dynamic softening and the lowest corresponding peak stress. Under the same compressive strain rate, the higher the deformation temperature, the lower the flow stress, demonstrating a significant high-temperature softening effect. As the deformation temperature increases, the dislocation migration ability and vacancy activity improve, making dislocations more prone to cross-slip and climb, thus reducing the flow stress.

[0051] like Figure 6 As shown, the specimen in Example 3 underwent deformation at four temperature stages: 430℃, 465℃, 500℃, and 535℃, with a deformation time of 0.1-10s. - ¹A comparison of true stress-true strain curves obtained from the combined strain rate process. This reveals the influence of temperature and strain rate on the true stress-true strain relationship and the dislocation density control law during the solution-hot deformation integration process.

[0052] Figure 6 The strain rate in (a) is 0.1 s⁻¹. -1 , Figure 6 The strain rate in (b) is 1 s. -1 , Figure 6 The strain rate in (c) is 10 s. -1 , Figure 6 The strain rate in (d) is 1 s. -1 .

[0053] Specifically, under the same compressive strain rate, the flow stress gradually decreases with increasing deformation temperature, exhibiting a significant high-temperature softening effect. This phenomenon is closely related to the migration ability of dislocations and the mobility of vacancies. As the deformation temperature increases, the mobility of dislocations strengthens, and they are more prone to cross-slip and climb, thus leading to a decrease in flow stress. At a strain rate of 0.1 s⁻¹... - Under the experimental conditions, the dynamic softening degree of the material increases significantly with increasing deformation, especially at lower deformation temperatures, where it exhibits more pronounced softening characteristics. like Figure 6 As shown in (a), aluminum alloys are more prone to softening at low temperatures, possibly because dislocation activity is suppressed under these conditions, resulting in a more pronounced softening process.

[0054] like Figure 6 As shown in (b), (c), and (d), that is, under high strain rate conditions, such as 1 s - ¹ and 10s - ¹, the rheological stress remains essentially stable after reaching a steady state. This phenomenon can be attributed to the fact that at high strain rates, the dislocation multiplication rate is significantly higher than the dislocation annihilation rate caused by dynamic recrystallization (DRV) or dynamic recovery (DRX), leading to an increase in deformation stress. This is consistent with the conclusions of existing literature, indicating that at high strain rates, the deformation mechanism of materials is mainly dominated by dislocation multiplication, while the dynamic softening effect does not significantly affect the rheological stress.

[0055] In 0.5s - ¹-1s - ¹Under strain rate conditions, experimental results show that the rheological stress still decreases with increasing temperature, but at high temperatures, the decrease in rheological stress is significantly less than 0.1 s⁻¹. - ¹ and 1s - ¹The condition. This is likely due to the condition at 0.5s. - ¹-1s - Within the strain rate range¹, the rheological behavior of the material exhibits certain nonlinear characteristics, leading to increased complexity in the variation of rheological stress. In other words, in actual processing, appropriate deformation conditions should be selected according to specific process requirements to optimize the formability of the aluminum alloy. Table 2 is a comparison table of the performance tests of cylindrical aluminum alloy specimens from Examples 1-3 and Comparative Examples 1-2.

[0056] Table 2

[0057] In summary, the method for controlling the B' / U2 composite phase in aluminum alloys provided by this invention has achieved significant technical effects in terms of the performance, process optimization, and industrial adaptation of aluminum alloys in power components, as detailed below: 1. Significantly improved precision in composite phase control Compared to Comparative Example 1 and Comparative Column 2, Examples 1-3 achieve better results by precisely controlling dislocation parameters (density 6.2 × 10¹). 4 m - ²-9.8×10¹ 4 m - The spacing (20nm-50nm) is matched with the process to ensure that the B' / U2 composite phase exhibits a directional distribution. The B' phase size is stable at 10nm-30nm, the U2 phase size is controlled at 5nm-15nm, and the composite phase number density is ≥1.5×10³ / μm². Furthermore, a uniform X-shaped distribution is formed in the easily deformable region. This effectively avoids the problems of long-range disorder and impurity phase inclusions in traditional processes, achieving quantifiable control over the morphology, size, and distribution of the composite phase, and solving the stringent requirements for microstructure consistency in power components.

[0058] 2. Mechanical properties are optimized in a coordinated manner and meet service requirements. As shown in Table 2, compared to Comparative Example 1 and Comparative Column 2, Examples 1-3 exhibit significantly improved overall mechanical properties due to the synergistic effect of grain refinement strengthening, dislocation strengthening, and B' / U2 composite phase precipitation strengthening. (The materials underwent solution treatment at 535℃ for 10 seconds.) - ¹After strain rate deformation and aging treatment at 180℃ for 6 hours, the yield strength of 6082 aluminum alloy can reach 302.1MPa and the hardness can reach 121.9HV, both of which far exceed the industry's strength requirements of 260MPa and 108HV. Among the core performance indicators of power components, the yield strength after aging is stable at 200-210MPa and the hardness is maintained at 88.1-91.5HV, which is more than double the original extruded state (yield strength 843MPa, hardness 49.8-52.9HV), fully meeting the performance requirements of components such as power spacers under complex service scenarios such as tensile and compressive loads and stress corrosion.

[0059] 3. Simultaneous optimization of process adaptability and production efficiency The integrated solution-deformation-quenching-aging process eliminates the need for multiple heating and solution steps, shortening the production process by more than 30%. The process parameters (535℃ solution, 10s...) are also optimized. - ¹Strain rate and 180℃ aging) are fully compatible with large-scale production lines for power components. The optimal forging parameters of 525℃ mold temperature and 300mm / s upper mold speed were determined through finite element simulation optimization, which reduced the peak load by 12%, increased the cavity filling rate by 9%, effectively avoided forming defects such as folding and incomplete filling, improved production efficiency by more than 40% compared with traditional processes, and reduced production costs by 30%-50%.

[0060] 4. Significantly enhanced organizational stability and service reliability. The synergistic effect of the B' / U2 composite phase effectively suppresses the coarsening of precipitated phases at high temperatures. After long-term service testing at 300℃, the material's performance degradation rate is less than 10%, far superior to products manufactured using traditional processes (with a degradation rate of over 40%). Simultaneously, the pinning effect of the composite phase at grain boundaries and dislocations inhibits abnormal grain growth, refining the average grain size to approximately 60μm after thermal deformation and increasing the proportion of high-angle grain boundaries to 59.5%. This significantly enhances the long-term service stability of power components in complex outdoor environments, extending their service life by more than two times.

[0061] 5. The regulatory mechanism is clear and has strong universality. The mechanism by which dislocations act as nucleation templates for the B' / U2 composite phase was clarified. Directional control of dislocation-induced precipitation was achieved by regulating deformation and strain rate. This mechanism is applicable to 6082 aluminum alloys with different Mg / Si ratios. For Mg-rich alloys, the precipitation path can be reversed through dislocation induction, promoting the formation of a phase structure with superior strengthening effect. For alloys with balanced composition, coarsening of the matrix precipitates can be effectively avoided, providing a unified technical solution for the performance customization of different types of aluminum alloy components in the power industry.

[0062] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of the claims of the present invention pending approval.

Claims

1. A method for controlling the B' / U2 composite phase in aluminum alloys, characterized in that, include: Solution treatment: The aluminum alloy is heated to the solution temperature and held at that temperature to form a supersaturated solid solution within the aluminum alloy; Deformation process: Compressing and deforming the aluminum alloy to form a dislocation structure inside the aluminum alloy; Quenching treatment: The deformed aluminum alloy is rapidly quenched to room temperature to retain the supersaturated solid solution and dislocation structure in the aluminum alloy; Aging treatment: Artificial aging is performed on quenched aluminum alloys to induce the directional precipitation of the B' / U2 composite phase along the dislocation structure in the aluminum alloy.

2. The method for controlling the B' / U2 composite phase in aluminum alloys according to claim 1, characterized in that, The heating rate for the solution treatment is 10℃ / s-15℃ / s, the solution temperature is 530℃-540℃, and the holding time is 10min-15min.

3. The method for controlling the B' / U2 composite phase in aluminum alloys according to claim 1, characterized in that, In the deformation treatment step, the aluminum alloy undergoes compressive deformation of 45%-55% at a strain rate of 0.1 s⁻¹. -1 -10s -1 .

4. The method for controlling the B' / U2 composite phase in aluminum alloys according to claim 1, characterized in that, In the deformation process, the aluminum alloy undergoes a single-stage unidirectional hot-pressing deformation at the solution treatment temperature.

5. The method for controlling the B' / U2 composite phase in aluminum alloys according to claim 1, characterized in that, The dislocation density forming the dislocation structure during the deformation process is 6.2 × 10⁻⁶. 14 m -2 -9.8×10 14 m -2 The dislocation spacing is 20nm-50nm.

6. The method for controlling the B' / U2 composite phase in aluminum alloys according to claim 1, characterized in that, In the deformation process, the aluminum alloy undergoes multiple unidirectional hot-pressing deformations at stepped temperatures ranging from 430℃ to 535℃.

7. The method for controlling the B' / U2 composite phase in aluminum alloys according to claim 5, characterized in that, The stepped temperatures are 430℃, 465℃, 500℃ and 535℃, respectively.

8. The method for controlling the B' / U2 composite phase in aluminum alloys according to claim 1, characterized in that, The aging temperature in the aging process is 175℃-185℃, and the aging time is 5h-7h.

9. The method for controlling the B' / U2 composite phase in aluminum alloys according to claim 1, characterized in that, The aging temperature in the aging process is 180℃, and the aging time is 6 hours.

10. The method for controlling the B' / U2 composite phase in aluminum alloys according to claim 1, characterized in that, The aforementioned control method is applicable to any one of the Mg / Si 6082 aluminum alloy system, Mg-rich aluminum alloy system, and balanced composition aluminum alloy system.

11. The method for controlling the B' / U2 composite phase in aluminum alloys according to claim 1, characterized in that, In the aging treatment step, the B' / U2 composite phase is uniformly distributed in an X-shape in the easily deformable region of the aluminum alloy. The B' phase size is 10nm-30nm, the U2 phase size is 5nm-15nm, and the B' / U2 composite phase number density is ≥1.5×10⁻⁶. 3 / μm 2 .

12. An aluminum alloy, characterized in that, It is processed using the method for controlling the B' / U2 composite phase in aluminum alloys as described in any one of claims 1-11.

13. The aluminum alloy according to claim 12, characterized in that, The aluminum alloy is used to manufacture electrical spacer bars.

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