Method for quantitatively determining distribution characteristics of excessive crystal phase particles in aluminum material

Abstract

The invention provides a simple, reliable, convenient and feasible sample preparation method for fully exposing excess crystal phase particles at different positions in an aluminum alloy deformed material. The technical problem that ultrasonic flaw detection, three-dimensional metallographic structure observation and other means cannot accurately and objectively measure and analyze the spatial distribution characteristics of the micron-sized crystal phase particles in the deformed aluminum alloy material is solved, and the measurement and analysis method for judging whether the crystal phase particles are aggregated and distributed or not is provided. The invention provides a statistical calculation method for evaluating the distribution uniformity of crystal phase particles. By utilizing the technical means of the invention, the spatial distribution characteristics of the excessive crystal phase particles in the aluminum material can be efficiently and accurately determined and analyzed, and the method can be used for further optimizing the spatial distribution characteristics of the excessive crystal phase particles in the aluminum material by virtue of a reasonable process regulation and control means. The necessary, objective and accurate method for obtaining the spatial distribution characteristic parameter data of the excessive crystal phase particles is provided for finally greatly improving the comprehensive performance of the aluminum material.

Description

Technical fields:

[0001] This invention belongs to the field of aluminum alloy technology and is a method for quantitatively determining and analyzing the spatial distribution characteristics (including particle size statistics, particle area fraction, particle aggregation distribution area size, particle spatial dispersion degree, etc.) of micron-sized excess crystalline phase particles in aluminum alloy extruded materials, forgings, rolled plates and other deformed materials. Background technology:

[0002] Aluminum alloy wrought iron profiles, as key structural materials, are widely used in the manufacture of high-speed rail car bodies, sleeper beams, side beams, traction beams, suspension tracks, and reinforcing plates; automotive body load-bearing components, including front pillars, middle pillars, body panels, and wheel hubs; aircraft panels, bulkheads, skins, wing spars, wing ribs, stringers, and nose cones; helicopter propeller blades; liquid hydrogen and liquid oxygen fuel storage tanks and their main structural components in rockets; and connecting frames, intermediate frames, skins, transition rings, and orbital module shell structures for manned spacecraft. To ensure the safety and reliability of rail transit car bodies, automobiles, and aerospace vehicles, aluminum materials must possess excellent mechanical properties, especially fatigue performance and fatigue damage tolerance. Micron-sized excess crystalline phase particles in aluminum alloys play a decisive role in fatigue crack initiation and propagation behavior, thus determining the fatigue performance and fatigue damage tolerance of the aluminum material. These micron-sized excess crystalline phase particles are an unavoidable alloying phase in aluminum alloys. During solidification, the aluminum alloy melt forms numerous dendritic micron-sized soluble or insoluble alloying phases. During the high-temperature, long-term homogenization process of the ingot, some of the soluble alloying phases dissolve, while the insoluble or incompletely dissolved alloying phase particles aggregate and grow into spheroids. These spheroidized alloying phase particles are broken up during subsequent ingot deformation and distributed planarly within a certain thickness layer of the deformed material. These micron-sized, hard, and brittle excess crystalline phase particles, distributed planarly along the thickness layer of the deformed material, have poor coordination with the matrix during deformation. When the matrix undergoes dislocation and slippage, they often accumulate at the particle interface fronts, causing significant stress concentration at the particle interface. Under concentrated stress, microcracks develop at the excess crystalline phase particle fronts, causing the particles to debond and separate from the matrix, becoming fatigue crack initiation points. In some cases, under concentrated stress, the micron-sized hard and brittle particles themselves fracture, forming microcracks. Therefore, the greater the number, size, uneven distribution, or obvious aggregation of excess crystalline phase particles in aluminum, the greater the stress concentration. This makes the alloy more prone to crack initiation and fracture during service, significantly reducing the tensile strength, elongation, fatigue strength, and fatigue damage tolerance of wrought aluminum alloys. Furthermore, the potential difference between coarse crystalline phase particles and the matrix in aluminum alloys easily leads to localized anodic dissolution corrosion. For example, the potential of the Al7Cu2Fe phase is higher than that of the aluminum matrix, causing the aluminum matrix to act as the anode and undergo galvanic corrosion dissolution.

[0003] In summary, micron-sized crystalline phase particles in aluminum alloys are detrimental to the tensile strength, elongation, fatigue strength, fatigue life, and corrosion resistance of aluminum alloys. The degree of adverse effect of crystalline phases on the properties of wrought aluminum alloys depends on the size and quantity of the crystalline phase particles, especially their spatial distribution characteristics (including the size of the aggregated distribution area and the spatial dispersion of the particles). Existing technologies typically utilize ultrasonic testing and metallographic observation and analysis of aluminum materials in three dimensions (cross-section, longitudinal section, and deformed surface) to determine and analyze the size, morphology, area fraction, and spatial distribution characteristics of excess crystalline phase particles in aluminum materials. However, ultrasonic testing has certain limitations on the thickness of aluminum materials, and this technology is difficult to identify micron-sized alloy phase particles; the sampling methods for metallographic observation and analysis cannot screen out the locations of micron-sized crystalline phase particle aggregation and distribution, and metallographic observation and analysis cannot construct the spatial distribution of particles in wrought alloy materials. Both existing techniques have significant limitations in determining and analyzing the spatial distribution characteristics of excess crystalline phase particles in aluminum materials, and cannot objectively and accurately determine and analyze the spatial distribution characteristics of excess crystalline phase particles in aluminum materials. This invention provides a practical, efficient, and accurate method for quantitatively measuring and analyzing spatial distribution characteristic parameters such as the statistical size of micron-sized crystalline phase particles, the statistical size of particle aggregation distribution regions, the degree of spatial dispersion of particles, and particle area fraction, for aluminum alloy deformable materials (including rolled plates, extruded materials, and forgings). Summary of the Invention:

[0004] The purpose of this invention is to provide a method for quantitatively determining and analyzing spatial distribution characteristics of micron-sized excess crystalline phase particles, including the size of particle aggregation regions, the degree of spatial dispersion, and the particle area fraction, in aluminum alloy extrusions, forgings, and rolled sheets. This method solves the problem that existing technologies cannot objectively and accurately determine and analyze the spatial distribution characteristics of micron-sized crystalline phase particles in deformed aluminum alloys. It also avoids the technical difficulties of objectively and accurately assessing the adverse effects of excess crystalline phase particles on aluminum properties and predicting the degree of deterioration. Using the technical means of this invention, the spatial distribution characteristics of excess crystalline phase particles in aluminum can be efficiently and accurately determined and analyzed. This provides a necessary, objective, and accurate method for obtaining spatial distribution characteristic data of excess crystalline phase particles, enabling further optimization of the spatial distribution characteristics of excess crystalline phase particles in aluminum through reasonable process control, ultimately significantly improving the overall performance of aluminum.

[0005] A method for determining the spatial distribution characteristics of excess crystalline phase particles in wrought aluminum alloys includes the following steps:

[0006] (1) Take samples from any position on the surface of the aluminum alloy deformed material to be observed: Randomly cut 6 samples with dimensions of approximately 10mm × 10mm × 5~8mm from different positions and thicknesses of the aluminum alloy deformed material in three dimensions, such as... Figure 1As shown, the purple and yellow samples are used to characterize the distribution characteristics of micron-sized excess crystalline phase particles in a selected thickness layer of the aluminum alloy wrought metal along the deformation direction and perpendicular to the deformation direction, respectively. The specific dimensions are 10 mm (along the deformation direction) × 10 mm (width direction) × 5–8 mm (thickness direction; if the thickness of the wrought metal is less than 5 mm, the full thickness of the wrought metal is cut off). The red and dark blue samples are used to characterize the distribution characteristics of micron-sized excess crystalline phase particles in the longitudinal section parallel to the deformation direction and in the thickness direction of the longitudinal section of the aluminum alloy wrought metal, respectively. The specific dimension is 10 mm (parallel to the deformation direction).

[0007] ×10mm (in the thickness direction; if the thickness of the deformed material is less than 10mm, then the full thickness of the deformed material is cut off)

[0008] ×5~8mm (width direction); green and light blue samples are used to characterize the distribution characteristics of micron-level excess crystalline phase particles in the width and thickness directions of the cross-section of aluminum alloy deformed material. The specific size is 10mm (width direction) × 10mm (thickness direction; if the thickness of the deformed material is less than 10mm, the full thickness of the deformed material is cut out) × 5~8mm (width direction).

[0009] Note: For aluminum alloy rolled sheets, the deformation direction is the rolling direction; for aluminum alloy extruded materials, the deformation direction is the extrusion direction; for aluminum alloy forgings, the deformation direction is the direction with the largest dimension in the three dimensions of the forging.

[0010] (2) Pre-cut notches along the dimensional direction of the particle configuration features to be observed: Use a hand saw or wire cutting method to cut a pre-cut notch of a certain size along the direction of the aluminum material to be observed for the sample cut in step (1).

[0011] (3) Tear the remaining part along the direction of the precast notch expansion: such as Figure 2 As shown, the remaining portion is torn along the expansion direction of the pre-formed notch in the aluminum material to expose excess crystalline phase particles in the surface to be observed and analyzed. Since the aggregation surface or location of micron-sized excess crystalline phase particles is the surface with the weakest bonding force in the aluminum material, when the remaining portion is torn along the pre-formed notch, the aluminum fracture always extends along the spatial path with the largest area fraction and the highest degree of aggregation of micron-sized excess crystalline phase particles, i.e., the fracture surface is torn (…). Figure 2 The medium gray area can best expose the micron-sized excess crystalline phase particles in the aluminum material.

[0012] (4) Protect the torn fracture surface: Place the two fracture surfaces after tearing into two clean sample bags respectively to avoid wear or contamination of the surface of the torn fracture surface to be observed and analyzed.

[0013] (5) Observation and analysis of the tear fracture surface: The surface of the tear fracture was observed using a scanning electron microscope. Figure 2In the medium gray area, photographs of crystalline phase particle characteristics were sequentially taken and stitched together on the torn fracture surface of ≤10mm (the direction to be observed) × 1~2mm (the other dimension of the surface to be observed) × 1~3mm (the other dimension of the deformable material besides the surface to be observed), to obtain, as shown in the image. Figure 3 ≤10mm shown

[0014] (The direction to be observed) × 1~2mm (another dimension of the surface to be observed) is used to quantitatively determine and analyze the size, aggregation distribution and distribution uniformity of excess crystalline phase particles in aluminum. During the image taking process, EDS energy dispersive spectroscopy analysis can be combined to determine the types of crystalline phase particles in aluminum.

[0015] (6) Determine and analyze the spatial distribution characteristics of crystalline phase particles: Use Nano Measurer software to determine the size of crystalline phase particles, the area fraction of particles, and the size of the region where crystalline phase particles are aggregated. The threshold for the aggregated distribution of crystalline phase particles is defined as the maximum equivalent diameter of a single particle among adjacent particles. When the distance between adjacent particles is greater than the maximum equivalent diameter of adjacent particles, the particles are considered to be discretely distributed. If the distance between adjacent particles is less than or equal to the maximum equivalent diameter of adjacent particles, the particles are considered to be aggregated.

[0016] (7) Determine the distribution and dispersion of crystalline phase particles in the torn fracture surface: Divide the entire torn fracture surface obtained by splicing in step (5) into X*Y parts (4≤X≤6, Y value satisfies: 1:2≤ aspect ratio of each part ≤1:1), and number each part sequentially as X. i Y j (i,j∈Z + ; 1≤i≤X; 1≤j≤Y), remove Z invalid image samples (such as completely blank images (no information) and partially blank images (incomplete information), and mark them with the "▲" symbol, such as Figure 3 As shown, the area fraction of crystalline phase particles in each valid image (X*YZ) was measured using ImageJ software and defined as S. ij (i,j∈Z + ; 1≤i≤X; 1≤j≤Y), calculate the average area fraction. (unit:%):

[0017]

[0018] (8) Determination of the uniformity of crystalline phase particle distribution in the torn fracture surface: The uniformity of crystalline phase particle distribution in aluminum alloy deformed materials is defined as A, where:

[0019]

[0020] The larger the uniformity A value of crystalline phase particle distribution, the more uneven the distribution of crystalline phase particles in the aluminum alloy wrought material.

[0021] The beneficial effects of this invention are:

[0022] (1) A simple, easy, objective and accurate method is provided to quantitatively characterize the spatial characteristics of micron-sized excess crystalline phase particles in aluminum alloy deformed materials (including particle area fraction, particle size and particle size distribution characteristics, major axis and minor axis of particle aggregation distribution, particle spatial distribution uniformity, etc.).

[0023] (2) It solved the technical problem that ultrasonic flaw detection and metallographic observation could not accurately and objectively determine and analyze the spatial distribution characteristics of micron-sized crystalline phase particles in aluminum alloy deformed materials.

[0024] Instruction manual illustrations:

[0025] Figure 1 This is a sampling diagram for determining the distribution characteristics of micron-sized excess crystalline phase particles in aluminum materials;

[0026] Figure 2 This is a schematic diagram of the sample preparation method for analyzing the distribution characteristics of crystalline phase particles in aluminum alloy deformed materials;

[0027] Figure 3 This is a schematic diagram of the SEM image stitched together and analysis diagram of the torn surface, representing a method for characterizing the uniformity of crystalline phase particle distribution in wrought aluminum alloys.

[0028] Figure 4 This document describes the cutting locations and observation surfaces of six samples used for the determination and analysis of the spatial distribution characteristics of micron-sized excess crystalline phase particles in a 25mm thick 2024 aluminum plate in commercial applications.

[0029] Figure 5 This is a method for preparing a sample for determining and analyzing the distribution characteristics of six excess crystalline phase particles in a 25mm thick 2024 aluminum plate used in commercial applications.

[0030] Figure 6 This is a composite image of SEM images of a torn surface and its measurement and analysis diagram, representing a method for characterizing the uniformity of crystalline phase particle distribution in six directions on a 25mm thick 2024 aluminum plate used in commercial applications.

[0031] Figure 7 This document describes the spatial distribution characteristics of micron-sized excess crystalline phase particles in the reinforcing ribs of a 6mm thick hollow thin-walled 6110A aluminum alloy profile, including the cutting locations and observation surfaces of six samples.

[0032] Figure 8 This is a sample preparation method for determining and analyzing the distribution characteristics of excess crystalline phase particles in six directions of the reinforcing ribs of a 6mm thick hollow thin-walled 6110A aluminum alloy profile.

[0033] Figure 9 This is a composite image of SEM images of the torn surface and its measurement and analysis diagram of a 6mm thick commercial 6110A aluminum extrusion sample with a 6mm thick reinforcing rib in six directions, which characterizes the uniformity of crystalline phase particle distribution in the six directions of the sample.

[0034] Figure 10 This document describes the spatial distribution characteristics of micron-sized excess crystalline phase particles in a 31mm thick 7050 aluminum forging, based on the cutting locations and observation surfaces of six samples.

[0035] Figure 11 This is a sample preparation method for determining and analyzing the distribution characteristics of excess crystalline phase particles in six directions in a commercially available 31mm thick 7050 aluminum forging.

[0036] Figure 12 This is a composite image of SEM images of the torn surface and its measurement and analysis diagram, representing the characterization method of uniformity of crystalline phase particle distribution in six directions for a 31mm thick 7050 aluminum forging in commercial use.

[0037] Figure 13 These are three-dimensional metallographic images of three types of aluminum alloy deformed materials; Specific implementation methods:

[0038] The present invention will be further described in detail below with reference to the embodiments.

[0039] Example 1

[0040] A quantitative analysis method for the distribution characteristics of micron-sized excess crystalline phase particles in a 25mm thick commercial 2024 aluminum plate. (e.g.) Figure 4 As shown in the figure, in this embodiment, six samples were cut from a commercially available 25mm thick 2024 aluminum plate, with the thickness layer along the rolling direction (purple sample), the thickness layer perpendicular to the rolling direction (yellow sample), the longitudinal section parallel to the rolling direction (red sample), the longitudinal section thickness direction (dark blue sample), the cross-sectional width direction (green sample), and the cross-sectional thickness direction (light blue sample). The thickness layer sample was cut at 1 / 4 of the plate thickness, while the longitudinal and cross-sectional samples were cut near the surface of the aluminum plate and at the center of the plate thickness, respectively. The specific directions of the sample cutting and the surfaces to be observed are as follows. Figure 4 As shown, RD represents the rolling direction; TD represents the width direction of the aluminum plate; and ND represents the thickness direction of the aluminum plate.

[0041] Includes the following steps:

[0042] (1) Samples were taken from commercial 25mm thick 2024 aluminum plates: Two samples with dimensions of approximately 10mm (along the rolling direction) × 10mm (plate width direction) × 6mm (plate thickness direction) were cut from any position in the 1 / 4 thickness layer of the aluminum plate. These samples were used to prepare specimens for measuring the crystalline phase particle configuration characteristics in the observation planes of the thickness layer along the rolling direction and perpendicular to the rolling direction, respectively. Samples with dimensions of approximately 10mm (plate thickness direction) × 10mm (parallel to the rolling direction) × 7mm (plate width direction) were cut from any position in the longitudinal section near any side of the aluminum plate surface.

[0043] Two samples were prepared to prepare specimens for measuring the crystalline phase particle configuration characteristics in the observation planes of the longitudinal section parallel to the rolling direction and the longitudinal section thickness direction, respectively. Two samples with dimensions of approximately 10 mm (plate width direction) × 10 mm (plate thickness direction) × 5 mm (rolling direction) were cut from any position on the cross-section of the aluminum plate's thickness center layer. These samples were prepared to prepare specimens for measuring the crystalline phase particle configuration characteristics in the observation planes of the cross-section width direction and the cross-section thickness direction, respectively.

[0044] (2) Pre-cut notches along the dimensional direction of the particle configuration characteristics to be observed: Using a hand saw, cut a pre-cut notch approximately 9 mm wide along the longitudinal section of the sample to be observed along the rolling direction. The notch expansion direction is perpendicular to the rolling direction. Figure 5 As shown in (a); a pre-cut notch approximately 8.5 mm wide was cut along the longitudinal section of the sample, perpendicular to the rolling direction, with the notch extending parallel to the rolling direction, as shown in (a). Figure 5 As shown in (b); with the longitudinal section parallel to the rolling direction, a pre-fabricated notch approximately 8 mm wide was cut along the rolling direction of the plate surface. The notch extends along the thickness direction of the longitudinal section, as shown in (b). Figure 5 (c)

[0045] As shown; a pre-made notch approximately 8 mm wide was sawn along the thickness direction of the sample in the longitudinal section. The notch expansion direction is parallel to the rolling direction along the longitudinal section of the plate. Figure 5 As shown in (d); a pre-made notch with a width of approximately 9 mm is sawn into the sample along the rolling direction perpendicular to the plate surface. The notch extends along the thickness direction of the plate surface, as shown in (d). Figure 5 As shown in (e); a pre-fabricated notch approximately 8 mm wide was cut into the sample for observing the cross-sectional thickness along the thickness direction of the longitudinal section plate. The notch extends along the width direction of the cross-sectional plate, as shown in (e). Figure 5 (f)

[0046] As shown;

[0047] (3) Tear the remaining part along the direction of the pre-made notch: Tear the remaining part along the direction of the pre-made notch of the 2024 aluminum plate to expose the excess crystalline phase particles in the surface to be observed and analyzed. Since the surface or location of the micron-sized excess crystalline phase particles is the weakest bonding surface of the aluminum plate, when the remaining part is torn along the pre-made notch, the fracture of the aluminum plate always extends along the spatial path with the largest area fraction and the greatest degree of aggregation of the micron-sized excess crystalline phase particles. That is, the torn fracture surface can expose the micron-sized excess crystalline phase particles of the 2024 aluminum plate to the greatest extent.

[0048] (4) Protect the torn fracture surface: Place the two fracture surfaces after tearing into two clean sample bags respectively to avoid wear or contamination of the surface of the torn fracture surface to be observed and analyzed;

[0049] (5) Observation and analysis of the tear fracture surface: Using a scanning electron microscope, photographs were taken sequentially along the desired observation direction for the tear fracture surface of six samples: the thickness layer along the rolling direction, the thickness layer perpendicular to the rolling direction, the longitudinal section parallel to the rolling direction, the longitudinal section thickness direction, the cross-sectional width direction, and the cross-sectional thickness direction. The images were then stitched together to obtain the following results: Figure 6 The following sizes are shown: 10mm (along the rolling direction) × 1mm (perpendicular to the rolling direction), 10mm (perpendicular to the rolling direction) × 1.5mm (along the rolling direction), 10mm (parallel to the rolling direction) × 2mm (thickness direction), 10mm (thickness direction) × 2mm (parallel to the rolling direction), 10mm (width direction) × 1mm (thickness direction), and 10mm (thickness direction) ×

[0050] A 2mm (width direction) tear fracture surface morphology photograph is used to quantitatively determine and analyze the characteristics of excess crystalline phase particles in aluminum plates, such as size, aggregation distribution area size range, distribution uniformity, and particle area fraction. During the SEM photograph taking process, EDS energy dispersive spectroscopy analysis is combined to determine the types of crystalline phase particles in aluminum plates.

[0051] (6) Determination of spatial distribution characteristics of crystalline phase particles: The size of crystalline phase particles, the area fraction of particles, and the size of the region where crystalline phase particles are aggregated were determined using Nano Measurer software. The threshold for the aggregation distribution of crystalline phase particles was defined as the maximum equivalent diameter of a single particle among adjacent particles. When the distance between adjacent particles is greater than the maximum equivalent diameter of adjacent particles, the particles are considered to be discretely distributed. If the distance between adjacent particles is less than or equal to the maximum equivalent diameter of adjacent particles, the particles are considered to be aggregated. The statistics are shown in Table 1.

[0052] Table 1. Statistics on the types and size distribution of excess crystalline phase particles in six directions of commercial 25mm thick 2024 aluminum plate samples.

[0053]

[0054]

[0055] (7) Determination of the distribution and dispersion of crystalline phase particles in the torn fracture surface: The distribution and dispersion of crystalline phase particles in a commercial 25mm thick 2024 aluminum plate were determined. Typical field-of-view photographs of the entire torn fracture surface of six samples obtained in step (5) along the rolling direction, perpendicular to the rolling direction, parallel to the rolling direction of the longitudinal section, the thickness direction of the longitudinal section, the width direction of the cross section, and the thickness direction of the cross section were evenly divided into X*Y parts (X=4, Y=10). Each part of the image was numbered sequentially as X. i Y j (i,j∈Z + ;1≤

[0056] i≤4; 1≤j≤10), remove Z invalid image samples (completely blank images (no information) and partially blank images (incomplete information), and mark them with the "▲" symbol, such as Figure 6 As shown, the area fraction of crystalline phase particles in each valid image was measured using ImageJ software and defined as S. ij (i,j∈

[0057] Z + (1≤i≤4; 1≤j≤10), the calculation results are shown in Table 2.

[0058] Table 2. Analysis results of excess crystalline phase particles in 4×10 samples from 6 directions of commercial 25mm thick 2024 aluminum plates (unit: %)

[0059]

[0060]

[0061] The results in Table 2 show the thickness of a 25mm thick 2024 aluminum plate along the rolling direction, perpendicular to the rolling direction, parallel to the rolling direction of the longitudinal section, in the thickness direction of the longitudinal section, in the width direction of the cross section, and in the cross section.

[0062] Average area fraction of excess crystalline phase particles in the thickness direction (unit:%):

[0063]

[0064] The calculation results are shown in Table 3;

[0065] (8) Determining the uniformity of crystalline phase particle distribution in the torn fracture surface: The uniformity of crystalline phase particle distribution in the aluminum plate is defined as...

[0066] The uniformity is A, where:

[0067]

[0068] Table 3 shows the calculated uniformity of excess crystalline phase particles in six samples of commercial 25mm thick 2024 aluminum plates: along the rolling direction, perpendicular to the rolling direction, parallel to the rolling direction of the longitudinal section, along the thickness direction of the longitudinal section, along the width direction of the cross section, and along the thickness direction of the cross section. It can be seen that the commercial 25mm thick 2024 aluminum plate has fewer crystalline phase particles in the parallel rolling direction of the longitudinal section and along the width direction of the cross section, with smaller maximum particle aggregation areas and more uniform particle spatial distribution. However, the aluminum plate has more crystalline particles in the thickness direction of the longitudinal section and along the thickness direction of the cross section, with larger maximum particle aggregation areas and stronger particle aggregation characteristics in spatial distribution.

[0069] Table 3. Statistical results of the area fraction and spatial distribution uniformity of excess crystalline phase particles in six directions of commercial 25mm thick 2024 aluminum plate samples.

[0070]

[0071] Example 2

[0072] A quantitative analysis of the distribution characteristics of micron-sized excess crystalline phase particles in a commercial 6110A aluminum alloy hollow thin-walled profile with a wall thickness of 6 mm and a width of 20 mm was conducted on the reinforcing ribs. Figure 7 As shown, in this embodiment, six full-thickness samples were cut from the reinforcing ribs of a 6mm thick hollow thin-walled 6110A aluminum alloy profile. These samples were taken along the extrusion direction (purple sample), perpendicular to the extrusion direction (yellow sample), parallel to the extrusion direction (red sample), along the thickness direction (dark blue sample), along the width direction (green sample), and along the thickness direction (light blue sample). ED represents the extrusion direction; TD represents the width direction of the extruded reinforcing rib; and ND represents the thickness direction of the extruded reinforcing rib.

[0073] Includes the following steps:

[0074] (1) Take samples from the reinforcing ribs of 6mm thick hollow thin-walled 6110A aluminum alloy profiles: Cut two samples with dimensions of approximately 10mm (along the extrusion direction) × 10mm (width direction of the extrusion rib) × 6mm (thickness direction of the extrusion rib) at any position on the full thickness layer of the aluminum extrusion rib. These samples are used to prepare specimens for measuring the crystalline phase particle configuration characteristics in the observation planes along the extrusion direction and perpendicular to the extrusion direction of the thickness layer, respectively; Cut two samples with dimensions of approximately 6mm (thickness direction of the extrusion rib) × 10mm (width direction of the extrusion rib) × 6mm (thickness direction of the extrusion rib) at any position on the longitudinal section of the extrusion rib. Two 10mm (parallel to the extrusion direction) × 7mm (width direction of the extruded material reinforcing rib) samples were used to prepare specimens for measuring the crystalline phase particle configuration characteristics in the observation planes of the longitudinal section in the parallel to the extrusion direction and the longitudinal section in the thickness direction, respectively. Two samples with dimensions of approximately 10mm (width direction of the extruded material reinforcing rib) × 6mm (thickness direction of the extruded material reinforcing rib) × 6mm (extrusion direction) were cut from any position on the cross-section of the extruded material reinforcing rib, respectively, for preparing specimens for measuring the crystalline phase particle configuration characteristics in the observation planes of the cross-section in the width direction and the cross-section in the thickness direction, respectively.

[0075] (2) Cut a notch along the dimension in which the particle configuration characteristics are to be observed: Using a hand saw, cut a pre-fabricated notch approximately 8.5 mm wide along the longitudinal section of the sample to be observed in the compression direction. The notch expansion direction is perpendicular to the compression direction. Figure 8 As shown in (a); when observing the sample with the thickness layer perpendicular to the extrusion direction, a pre-fabricated notch with a width of approximately 8.5 mm is cut along the longitudinal section parallel to the extrusion direction. The notch extends in the direction parallel to the extrusion direction, as shown in (a). Figure 8 As shown in (b); when observing the sample with the longitudinal section parallel to the extrusion direction, a pre-fabricated notch with a width of approximately 4.5 mm is cut along the extrusion direction of the reinforcing rib. The notch extends along the thickness direction of the longitudinal section of the reinforcing rib, as shown in (b). Figure 8 As shown in (c); a prefabricated notch approximately 9 mm wide was cut along the thickness direction of the reinforcing rib in the longitudinal section of the sample. The notch expansion direction is parallel to the extrusion direction along the longitudinal section of the reinforcing rib. Figure 8 As shown in (d); when observing the sample in the width direction of the cross-section, use a hand saw or wire cutting method to cut a pre-fabricated notch approximately 5mm wide along the upper surface of the reinforcing rib perpendicular to the extrusion direction. The notch extends along the thickness direction of the upper surface of the reinforcing rib, as shown in (d). Figure 8 As shown in (e); a prefabricated notch approximately 8 mm wide was cut into the cross-sectional thickness observation sample along the longitudinal cross-sectional thickness direction of the reinforcing rib, with the notch extending along the cross-sectional width direction of the reinforcing rib, as shown. Figure 8 As shown in (f);

[0076] (3) Tear the remaining part along the direction of the pre-formed notch: Tear the remaining part along the direction of the pre-formed notch of the six 6110A aluminum extrusion reinforcing ribs to expose the excess crystalline phase particles in the surface to be observed and analyzed. Since the surface or location of the micron-sized excess crystalline phase particles is the weakest bonding force of the aluminum extrusion reinforcing rib, when the remaining part is torn along the pre-formed notch, the fracture of the aluminum extrusion reinforcing rib always extends along the spatial path with the largest area fraction and the greatest degree of aggregation of the micron-sized excess crystalline phase particles. That is, the torn fracture surface can expose the micron-sized excess crystalline phase particles of the 6110A aluminum extrusion reinforcing rib to the greatest extent.

[0077] (4) Protect the torn fracture surface: Place the two fracture surfaces after tearing into two clean sample bags respectively to avoid wear or contamination of the surface of the torn fracture surface to be observed and analyzed;

[0078] (5) Observation and analysis of the tear fracture surface: Using a scanning electron microscope, photographs were taken sequentially along the desired observation direction of the tear fracture surface of six samples: the thickness layer along the extrusion direction, the thickness layer perpendicular to the extrusion direction, the longitudinal section parallel to the extrusion direction, the longitudinal section thickness direction, the cross-sectional width direction, and the cross-sectional thickness direction. These photographs were then stitched together to obtain the following results: Figure 9 The figures shown are 10mm (along the extrusion direction) × 1.5mm (perpendicular to the extrusion direction), 10mm (perpendicular to the extrusion direction) × 1.5mm (along the extrusion direction), 10mm (parallel to the extrusion direction) × 1.5mm (in the direction of the reinforcing rib thickness), and 6mm (in the direction of the reinforcing rib thickness) × 1.

[0079] Tear fracture surface morphology photographs of 10 mm (parallel to the extrusion direction), 10 mm (reinforcing rib width direction) × 1 mm (reinforcing rib thickness direction), and 6 mm (reinforcing rib thickness direction) × 2 mm (reinforcing rib width direction) were taken to quantitatively determine and analyze the characteristics of excess crystalline phase particles in the reinforcing ribs of 6110A aluminum alloy hollow thin-walled profiles, such as the size, aggregation distribution area, distribution uniformity, and particle area fraction. During the SEM photograph taking process, EDS energy dispersive spectroscopy analysis was combined to determine the types of crystalline phase particles in the reinforcing ribs of aluminum extrusions.

[0080] (6) Determine the spatial distribution characteristics of crystalline phase particles: The size, particle area fraction, and size of the aggregated distribution area of ​​crystalline phase particles in the reinforcing ribs of aluminum extrusion were determined using Nano Measurer software. The threshold for the aggregated distribution of crystalline phase particles was defined as the maximum equivalent diameter of a single particle in adjacent particles. When the distance between adjacent particles is greater than the maximum equivalent diameter of adjacent particles, the particles are considered to be discretely distributed. If the distance between adjacent particles is less than or equal to the maximum equivalent diameter of adjacent particles, the particles are considered to be aggregated. The statistical results are shown in Table 4.

[0081] Table 4. Statistics on the types and size distribution of excess crystalline phase particles in six directions of 6mm thick hollow thin-walled profiles made of commercial 6110A aluminum alloy.

[0082]

[0083]

[0084] (7) Determine the distribution and dispersion of crystalline phase particles in the torn fracture surface: Determine the distribution and dispersion of crystalline phase particles in the reinforcing ribs of 6mm thick commercial 6110A aluminum extrusion. The typical field-of-view mosaics of the entire torn fracture surface of 6 samples obtained in step (5) along the extrusion direction, the thickness layer perpendicular to the extrusion direction, the longitudinal section parallel to the extrusion direction, the longitudinal section thickness direction, the cross-sectional width direction, and the cross-sectional thickness direction are all divided into X*Y parts (X=5, Y=10). Each part of the image is numbered X. i Y j (i,j∈Z + (1≤i≤5; 1≤j≤10), after removing invalid image samples (such as completely blank images (no information)).

[0085] And some blank images (incomplete information), marked with "▲", and invalid image samples were removed, resulting in Z samples, such as... Figure 9 As shown,

[0086] The area fraction of crystalline phase particles in each valid image (the remaining sample after deleting images with no or incomplete information) was measured using ImageJ software and defined as S. ij (i,j∈Z + ; 1≤i≤

[0087] 5; 1≤j≤10), the calculation results are shown in Table 5.

[0088] Table 5. Analysis results of excess crystalline phase particles in six directions of 5 × 10 parts of images from 6mm thick commercial 6110A aluminum extrusions (unit: %).

[0089]

[0090]

[0091] Based on the results in Table 5, the average area fraction of excess crystalline phase particles was calculated for the 6mm thick reinforcing rib layer along the extrusion direction, perpendicular to the extrusion direction, parallel to the longitudinal section in the extrusion direction, in the longitudinal section thickness direction, in the cross-sectional width direction, and in the cross-sectional thickness direction of commercial 6110A aluminum extrusion. (unit:%):

[0092]

[0093] The calculation results are shown in Table 6;

[0094] (8) Determining the uniformity of crystalline phase particle distribution in the fracture surface: defining the crystalline phase in the reinforcing ribs of aluminum extrusions.

[0095] The particle distribution uniformity is A, where:

[0096]

[0097] Table 6 shows the calculated uniformity of excess crystalline phase particles in six samples of 6mm thick commercial 6110A aluminum extruded material, including the reinforcing rib thickness layer along the extrusion direction, the thickness layer perpendicular to the extrusion direction, the longitudinal section parallel to the extrusion direction, the longitudinal section thickness direction, the cross-sectional width direction, and the cross-sectional thickness direction. It can be seen that the number of crystalline phase particles in the cross-sectional width and thickness directions of the 6mm thick reinforcing rib of the commercial 6110A aluminum extruded material is relatively small, the maximum size of the particle aggregation distribution area is small, and the spatial distribution of particles is relatively uniform. However, the number of crystalline phase particles along the extrusion direction and perpendicular to the extrusion direction of the reinforcing rib thickness layer is larger, the maximum size of the particle aggregation distribution area is larger, and the spatial distribution of particles exhibits more obvious aggregation characteristics.

[0098] Table 6. Statistical results of excess crystalline phase particles and particle spatial distribution uniformity in six samples of 6mm thick reinforcing ribs for commercial 6110A aluminum extrusion.

[0099]

[0100] Example 3

[0101] A quantitative analysis method for the distribution characteristics of micron-sized excess crystalline phase particles in commercially available 31mm thick 7050 aluminum forgings. (e.g.) Figure 10 As shown in the figure, in this embodiment, six samples were cut from a commercially available 31mm thick 7050 aluminum forging. These samples were taken along the principal strain direction (purple sample), perpendicular to the principal strain direction (yellow sample), parallel to the principal strain direction in the longitudinal section (red sample), along the thickness direction in the longitudinal section (dark blue sample), along the width direction in the cross section (green sample), and along the thickness direction in the cross section (light blue sample). The forging thickness sample was taken at half the thickness of the forging. The longitudinal and cross-sectional samples were taken from the surface near the aluminum forging and the center layer of the aluminum forging, respectively, to characterize the spatial distribution of micron-sized excess crystalline phase particles in the aluminum forging. FD represents the principal strain direction; TD represents the width direction of the aluminum forging; and ND represents the thickness direction of the aluminum forging.

[0102] Includes the following steps:

[0103] (1) Samples were taken from commercially available 31mm thick 7050 aluminum forgings: Two samples with dimensions of approximately 10mm (principal strain direction) × 10mm (forging width direction) × 5mm (forging thickness direction) were cut from any position in the 1 / 2 thickness layer of the aluminum forging. These samples were used to determine the crystalline phase particle configuration characteristics in the observation planes along the principal strain direction and perpendicular to the principal strain direction of the prepared thickness layer, respectively. Samples with dimensions of approximately 10mm (forging thickness direction) × 10mm (principal strain direction) × 5mm were also cut from any position in the longitudinal section near any side of the aluminum forging surface.

[0104] Two 8mm (forging width direction) samples were used to prepare specimens for measuring the crystalline phase particle configuration characteristics in the observation planes parallel to the principal strain direction and the thickness direction of the longitudinal section, respectively; two samples with dimensions of approximately 10mm (forging width direction) × 10mm (forging thickness direction) × 7mm (principal strain direction) were cut from any position on the cross-section of the aluminum forging's thickness center layer, respectively, for preparing specimens for measuring the crystalline phase particle configuration characteristics in the observation planes in the cross-sectional width direction and the cross-sectional thickness direction;

[0105] (2) Cutting a notch along the dimension in which the particle configuration characteristics are to be observed: Using a wire cutting method, a pre-fabricated notch approximately 8.5 mm wide is cut along the longitudinal section of the sample to be observed along the principal strain direction. The notch extends along the width of the forging. Figure 11 As shown in (a); a pre-fabricated notch with a width of approximately 8.5 mm was cut along the longitudinal section of the sample, perpendicular to the principal strain direction and parallel to the principal strain direction. The notch expansion direction is parallel to the principal strain direction of the forging. Figure 11 As shown in (b); a pre-fabricated notch with a width of approximately 9 mm was cut along the principal strain direction of the thickness layer of the sample, with the notch extending along the thickness direction of the forging, as shown in (b). Figure 11 As shown in (c); a pre-fabricated notch with a width of approximately 8 mm was cut along the thickness direction of the cross-section forging of the sample observed in the longitudinal section thickness direction. The notch expansion direction is parallel to the principal strain direction, as shown in (c). Figure 11 As shown in (d), a pre-fabricated notch with a width of approximately 9 mm was cut into the sample observed in the width direction of the cross-section, perpendicular to the principal strain direction of the thickness layer. The notch extends along the thickness direction of the forging, as shown in the figure.

[0106] As shown in 11(e); the cross-sectional thickness observation sample was cut along the thickness direction of the longitudinal section of the forging, with a width of approximately 8.5 mm.

[0107] A pre-formed notch of mm, the notch expansion direction is along the width direction of the forging, such as... Figure 11 As shown in (f);

[0108] (3) Tear the remaining part along the direction of the pre-formed notch: Tear the remaining part along the direction of the pre-formed notch of the 7050 aluminum forging to expose the excess crystalline phase particles in the surface to be observed and analyzed. Since the surface or location of the accumulation of micron-sized excess crystalline phase particles is the surface with the weakest bonding force of the aluminum forging, when the remaining part is torn along the pre-formed notch, the fracture of the aluminum forging always extends along the spatial path with the largest area fraction and the greatest degree of accumulation of micron-sized excess crystalline phase particles. That is, the micron-sized excess crystalline phase particles of the 7050 aluminum forging can be exposed to the greatest extent in the torn fracture surface.

[0109] (4) Protect the torn fracture surface: Place the two fracture surfaces after tearing into two clean sample bags respectively to avoid wear or contamination of the surface of the torn fracture surface to be observed and analyzed;

[0110] (5) Observation and analysis of the tear fracture surface: The tear fracture surface was observed using a scanning electron microscope. Photographs were taken sequentially along the desired observation direction for the tear fracture surface of the sample in the following directions: along the principal strain direction of the thickness layer, perpendicular to the principal strain direction of the thickness layer, parallel to the principal strain direction of the longitudinal section, the thickness direction of the longitudinal section, the width direction of the cross section, and the thickness direction of the cross section. These images were then stitched together to obtain the following results: Figure 12 The following features are used to analyze the characteristics of excess crystalline phase particles on the tear fracture surfaces of 10mm (along the principal strain direction) × 1.5mm (perpendicular to the principal strain direction), 10mm (perpendicular to the principal strain direction) × 1.5mm (along the principal strain direction), 10mm (parallel to the principal strain direction) × 1mm (forging thickness direction), 10mm (forging thickness direction) × 2mm (parallel to the principal strain direction), 10mm (forging width direction) × 1mm (forging thickness direction), and 10mm (forging thickness direction) × 1.5mm (forging width direction). These features are combined with the information obtained during the SEM imaging process.

[0111] EDS energy dispersive spectroscopy analysis was used to determine the types of crystalline phase particles in aluminum forgings;

[0112] (6) Determine the spatial distribution characteristics of crystalline phase particles: The size of crystalline phase particles and the size of the region where crystalline phase particles are aggregated in aluminum forgings were determined using Nano Measurer software. The threshold for the aggregation distribution of crystalline phase particles was defined as the maximum equivalent diameter of a single particle in adjacent particles. When the distance between adjacent particles is greater than the maximum equivalent diameter of adjacent particles, the particles are considered to be discretely distributed. If the distance between adjacent particles is less than or equal to the maximum equivalent diameter of adjacent particles, the particles are considered to be aggregated. The statistical results are shown in Table 7.

[0113] Table 7. Statistics on the types and size distribution of excess crystalline phase particles in six directions of 31mm thick commercial 7050 aluminum forgings.

[0114]

[0115]

[0116] (7) Determine the distribution and dispersion of crystalline phase particles in the torn fracture surface: Determine the distribution and dispersion of crystalline phase particles in a 31mm thick 7050 aluminum alloy forging. The typical field-of-view photographs of the entire torn fracture surface of the six samples obtained in step (5) along the principal strain direction, the thickness layer perpendicular to the principal strain direction, the longitudinal section parallel to the principal strain direction, the longitudinal section thickness direction, the cross-sectional width direction, and the cross-sectional thickness direction are averaged and divided into X*Y parts (X=5, Y=10). Each part of the image is numbered sequentially as X. i Y j (i,j∈

[0117] Z + ; 1≤i≤5; 1≤j≤10), after removing invalid image samples (such as completely blank images (no information) and partially blank images (incomplete information), and marked with the "▲" symbol, the number of invalid image samples removed is Z), such as Figure 12 As shown, the area fraction of crystalline phase particles in each valid image was measured using ImageJ software and defined as S. ij (i,j∈Z + ;1≤i≤5;1≤j≤10), the calculation results are shown in Table 8; Table 8: Analysis results of excess crystalline phase particles in 5×10 samples of 31mm thick 7050 aluminum forgings from 6 directions (unit: %)

[0118]

[0119]

[0120] Based on the results in Table 8, the average area fraction of excess crystalline phase particles was calculated along the principal strain direction, perpendicular to the principal strain direction, parallel to the principal strain direction in the longitudinal section, in the thickness direction of the longitudinal section, in the width direction of the cross section, and in the thickness direction of the cross section for commercial 31mm thick 7050 aluminum forgings. (unit:%):

[0121]

[0122] The calculation results are shown in Table 9;

[0123] (8) Determine the uniformity of crystalline phase particle distribution in the torn fracture surface: Define the distribution of crystalline phase particles in aluminum forgings

[0124] The uniformity is A, where:

[0125]

[0126] A higher uniformity (A) of crystalline phase particle distribution indicates a more uneven distribution of crystalline phase particles in the aluminum forging. Table 9 shows the calculated uniformity of excess crystalline phase particles in the thickness layer of a commercial 31mm thick 7050 aluminum forging along the principal strain direction, perpendicular to the principal strain direction, parallel to the principal strain direction in the longitudinal section, in the thickness direction of the longitudinal section, in the width direction of the cross section, and in the thickness direction of the cross section. It can be seen that the maximum size of the aggregated distribution area of ​​crystalline phase particles in the thickness direction and the width direction of the cross section of the commercial 31mm thick 7050 aluminum alloy forging is smaller, with a smaller uniformity (A) and a more uniform spatial distribution of particles. However, the maximum size of the aggregated distribution area along the principal deformation direction and parallel to the principal strain direction in the thickness layer of the aluminum forging is larger, with a larger uniformity (A), indicating a stronger aggregated distribution characteristic in the spatial distribution of particles.

[0127] Table 9. Statistics on the uniformity of excess crystalline phase particles in six directions for commercial 31mm thick 7050 aluminum forgings.

[0128]

[0129] Comparative Example

[0130] The three-dimensional metallographic structure of the aluminum alloy deformed materials used in the above three embodiments (commercial 25mm thick 2024 aluminum plate, commercial 6110A aluminum alloy hollow thin-walled profile with 6mm wall thickness reinforcing ribs, and commercial 31mm thick 7050 aluminum forgings) was observed. The sampling and observation positions were the same as those in the corresponding embodiments above. The observation results are as follows: Figure 13 Therefore, compared with traditional three-dimensional metallographic imaging techniques for characterizing the distribution of excess crystalline phase particles in aluminum, the quantitative determination technique for the distribution of excess crystalline phase particles in aluminum proposed in this invention has the following three advantages and innovations:

[0131] (1) Traditional metallographic sample preparation methods cannot screen out the location of micron-sized crystalline phase particles, and cannot expose the micron-sized excess crystalline phase particles in the observation direction of aluminum alloy deformed materials to the greatest extent. However, the present invention is based on the principle that the surface or location of micron-sized excess crystalline phase particles is the surface with the weakest bonding force of aluminum material. When the remaining part is torn along the pre-made notch, the aluminum material fracture always extends along the spatial path with the largest area fraction and the greatest degree of aggregation of micron-sized excess crystalline phase particles. Therefore, the method of pre-making a notch and then tearing the cross-section used in the present invention can expose the micron-sized excess crystalline phase particles in aluminum deformed materials to the greatest extent.

[0132] (2) Metallographic observation can only reflect the distribution characteristics of crystalline phase particles in a plane to a certain extent in aluminum wrought metals. Even if three cross-sections are observed and a structure is constructed, the results are not comprehensive. Figure 13The three-dimensional metallographic images shown also fail to determine the spatial distribution of particles in the deformed material because the three samples are not in-situ samples, and the spatial distribution of excess crystalline phase particles in the alloy deformed material cannot be constructed from the metallographic structures of three directions. This invention, through the preparation of 3...

[0133] The test results, consisting of six samples in six directions across six dimensions, are comprehensive, objective, and valid.

[0134] (3) Metallographic observation of aluminum wrought metals cannot determine the types of alloy phase particles and cannot quantitatively analyze the uniformity of the distribution of crystalline phase particles. The method used in this invention can determine the types of crystalline phase particles by means of EDS analysis when taking SEM images. More importantly, this invention proposes a concept for determining the aggregation and distribution of excess crystalline phase particles and establishes a calculation method for measuring the uniformity of particle distribution.

[0135] The above description is merely a preferred embodiment of this disclosure and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in the embodiments of this disclosure is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in the embodiments of this disclosure.

Claims

1. A method for determining the spatial distribution characteristics of excess crystalline phase particles in wrought aluminum alloys, comprising the following steps: (1) Take samples from any position on the surface of the aluminum alloy deformed material to be observed: Randomly cut six samples with dimensions of approximately 10mm × 10mm × 5-8mm in three dimensions from different positions and thicknesses of the aluminum alloy deformed material. Among them, two samples with dimensions of 10mm (along the deformation direction) × 10mm (width direction) × 5-8mm (thickness direction; if the thickness of the deformed material is less than 5mm, the full thickness of the deformed material is cut) are used to characterize the distribution characteristics of micron-level excess crystalline phase particles in the selected thickness layer of the aluminum alloy deformed material along the deformation direction and perpendicular to the deformation direction, respectively; and two samples with dimensions of 10mm (parallel to the deformation direction) × 10mm × 5-8mm are used to characterize the distribution characteristics of micron-level excess crystalline phase particles in the selected thickness layer of the aluminum alloy deformed material along the deformation direction and perpendicular to the deformation direction, respectively. Two samples with dimensions of 10mm (thickness direction; if the thickness of the deformed material is less than 10mm, the full thickness of the deformed material is cut) × 5-8mm (width direction) are used to characterize the distribution characteristics of micron-sized excess crystalline phase particles in the longitudinal section parallel to the deformation direction and the longitudinal section thickness direction of the aluminum alloy deformed material, respectively; two samples with dimensions of 10mm (width direction) × 10mm (thickness direction; if the thickness of the deformed material is less than 10mm, the full thickness of the deformed material is cut) × 5-8mm (width direction) are used to characterize the distribution characteristics of micron-sized excess crystalline phase particles in the cross-section width direction and the cross-section thickness direction of the aluminum alloy deformed material, respectively. Note: For rolled aluminum alloy sheets, the deformation direction is the rolling direction; for extruded aluminum alloys... The deformation direction is the extrusion direction; for aluminum alloy forgings, the deformation direction is the direction with the largest dimension in the three-dimensional dimensions of the forging. (2) Pre-cut notches along the dimensional direction of the particle configuration features to be observed: Use a hand saw or wire cutting method to cut a pre-cut notch of a certain size along the direction of the aluminum material to be observed for the sample cut in step (1). (3) Tear the remaining part along the expansion direction of the pre-fabricated notch: Tear the remaining part along the expansion direction of the pre-fabricated notch of the aluminum material. The torn surface is the surface where the excess crystalline phase particle configuration is to be observed, measured and analyzed. Since the aggregation surface or aggregation position of the micron-sized excess crystalline phase particles is the surface with the weakest bonding force of the aluminum material, when the remaining part is torn along the pre-fabricated notch, the aluminum material fracture always extends along the spatial path with the largest area fraction and the greatest degree of aggregation of the micron-sized excess crystalline phase particles. That is, the torn fracture surface can expose the micron-sized excess crystalline phase particles in the aluminum material to the greatest extent. (4) Protect the torn fracture surface: Place the two fracture surfaces after tearing into two clean sample bags respectively to avoid wear or contamination of the surface of the torn fracture surface to be observed and analyzed; (5) Observation and analysis of the surface of the tear fracture: The surface of the tear fracture is observed using a scanning electron microscope. The crystalline phase particle characteristic photos of the tear fracture surface with a diameter of ≤10mm (the direction to be observed) × 1~2mm (the other dimension of the surface to be observed) × 1~3mm (the other dimension of the deformed material) are photographed and stitched together to obtain the morphology photos of the tear fracture surface with a diameter of ≤10mm (the direction to be observed) × 1~2mm (the other dimension of the surface to be observed). These photos are used to quantitatively determine and analyze the size, aggregation distribution and distribution uniformity of excess crystalline phase particles in aluminum. During the process of taking pictures, the type of crystalline phase particles in aluminum can be determined by combining EDS energy dispersive spectroscopy analysis. (6) Determine and analyze the spatial distribution characteristics of crystalline phase particles: Use Nano Measurer software to determine the size of crystalline phase particles, the area fraction of particles, and the size of the region where crystalline phase particles are aggregated. The threshold for the aggregated distribution of crystalline phase particles is defined as the maximum equivalent diameter of a single particle among adjacent particles. When the distance between adjacent particles is greater than the maximum equivalent diameter of adjacent particles, the particles are considered to be discretely distributed. If the distance between adjacent particles is less than or equal to the maximum equivalent diameter of adjacent particles, the particles are considered to be aggregated. (7) Determine the distribution and dispersion of crystalline phase particles in the torn fracture surface: Divide the entire torn fracture surface obtained by splicing in step (5) into X*Y parts (4≤X≤6, Y value satisfies: 1:2≤ aspect ratio of each part ≤1:1), and number each part sequentially as X. i Y j (i,j∈Z + ; 1≤i≤X; 1≤j≤Y), remove Z invalid image samples (such as completely blank images (no information) and partially blank images (incomplete information), and label them with symbols). Use ImageJ software to measure the area fraction of crystalline phase particles in each valid image (X*YZ), and define it as S. ij (i,j∈Z + ; 1≤i≤X;1≤j≤Y), Calculate the average area fraction (unit:%): (8) Determination of the uniformity of crystalline phase particle distribution in the torn fracture surface: The uniformity of crystalline phase particle distribution in aluminum alloy deformed materials is defined as A, where: The larger the uniformity A value of crystalline phase particle distribution, the more uneven the distribution of crystalline phase particles in the aluminum alloy wrought material.

2. The method for quantitatively determining the distribution characteristics of excess crystalline phase particles in aluminum materials according to claim 1, characterized in that, In steps (2) and (3), a method for preparing an aluminum wrought metal sample for observing the excess crystalline phase particle configuration can be used to expose excess crystalline phase particles in aluminum to the greatest extent. Specifically, it involves using a hand saw or wire cutting to cut a pre-made notch of a certain size along the direction of the aluminum material where the particle configuration characteristics are to be observed. Then, the remaining part is torn along the expansion direction of the pre-made notch. Since the aggregation surface or aggregation position of the micron-sized excess crystalline phase particles is the surface with the weakest bonding force of the aluminum material, when the remaining part is torn along the pre-made notch, the aluminum material fracture always extends along the spatial path with the largest area fraction and the greatest degree of aggregation of the micron-sized excess crystalline phase particles. That is, the torn fracture surface can expose the micron-sized excess crystalline phase particles in the aluminum material to the greatest extent.

3. The method for quantitatively determining the distribution characteristics of excess crystalline phase particles in aluminum materials according to claim 1, characterized in that, In step (6), a method for determining the aggregation distribution of crystalline phase particles is provided. Specifically, this includes defining the threshold for the aggregation distribution of crystalline phase particles as the maximum equivalent diameter of a single particle among adjacent particles. When the distance between adjacent particles is greater than the maximum equivalent diameter of adjacent particles, the particles are considered to be discretely distributed. If the distance between adjacent particles is less than or equal to the maximum equivalent diameter of adjacent particles, the particles are considered to be aggregated.

4. The method for quantitatively determining the distribution characteristics of excess crystalline phase particles in aluminum materials according to claim 1, characterized in that, In step (7), a method for calculating the area fraction of crystalline phase particles is described. Specifically, this includes defining the area fraction of excess crystalline phase particles in each image as S. ij (i,j∈Z + ; (1≤i≤X; 1≤j≤Y), use formula -1 to calculate the average area fraction of all images. (unit:%): Where X*Y represents the total number of sample images, and Z represents the number of invalid image samples.

5. The method for quantitatively determining the distribution characteristics of excess crystalline phase particles in aluminum materials according to claim 1, characterized in that, In step (8), a method for calculating the uniformity of crystalline phase particle distribution is provided. Specifically, this includes defining the uniformity of crystalline phase particle distribution in aluminum alloy wrought metal as A, and calculating the uniformity A using formula -2, where i,j∈Z. + ; 1≤i≤X; 1≤j≤Y, where X*Y is the total number of sample images and Z is the number of invalid image samples: The larger the uniformity A value of crystalline phase particle distribution, the more uneven the distribution of crystalline phase particles in the aluminum alloy wrought material.

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