Al-Cu-Mg-Fe-Ni aluminum alloy bar and preparation method and application thereof

Abstract

The invention discloses an Al-Cu-Mg-Fe-Ni aluminum alloy bar as well as a preparation method and application of the Al-Cu-Mg-Fe-Ni aluminum alloy bar. The aluminum alloy bar comprises the following components in percentage by weight: less than or equal to 0.02% of Si, 0.7%-0.9% of Fe, 1.8%-2.1% of Cu, 1.3%-1.4% of Mg, 0.02%-0.08% of Ti, 0.7%-0.9% of Ni, more than or equal to 0.1% and less than or equal to 0.2% of Mn + Cr + Zr, and the balance of Al and inevitable impurities. The single impurity is less than or equal to 0.05%, the total impurity is less than or equal to 0.1% and the balance is Al, and the total percentage is 100%. When the aluminum alloy bar is extruded, the heating temperature of the head of the aluminum alloy ingot is higher than that of the tail; the front-section extrusion speed of the ingot is higher than the rear-section extrusion speed. Metal grains in the aluminum alloy bar are fine and uniform, the use requirements of the grains are met, the tensile strength of the bar is larger than or equal to 355MPa, and the ductility is larger than or equal to 8.0%.

Description

Technical Field

[0001] The present invention relates to the technical field of metal materials, and in particular to an Al-Cu-Mg-Fe-Ni aluminum alloy bar and a preparation method and application thereof. Background Art

[0002] Al-Cu-Mg-Fe-Ni aluminum alloy is a heat-treatable aluminum alloy. The Al9FeNi, Al7Cu4Ni, and Al2CuMg phases in the alloy give it good heat resistance and mechanical properties. It is widely used in the defense industry and aerospace fields. It has good hot and cold processing properties and moderate welding properties. It is suitable for manufacturing parts used at higher temperatures and is mostly used in aircraft engine pistons and ship materials. Al-Cu-Mg-Fe-Ni aluminum alloy extrusions have high technical requirements, especially strict requirements on grain size and uniformity.

[0003] At present, the Al-Cu-Mg-Fe-Ni aluminum alloy bars produced domestically generally have uneven and coarse grains, resulting in a very low yield rate. This not only increases production costs, but also seriously affects the demand for this material in the aviation field and corporate benefits. Summary of the invention

[0004] The main purpose of the present invention is to provide an Al-Cu-Mg-Fe-Ni aluminum alloy bar and a preparation method and application thereof, so as to solve the problems in the prior art that the aluminum alloy bar has coarse grains, uneven grains and mechanical properties that need to be improved.

[0005] In order to achieve the above object, according to one aspect of the present invention, an Al-Cu-Mg-Fe-Ni aluminum alloy bar is provided, which comprises the following components in weight percentage:

[0006] Si≤0.02,Fe 0.7%~0.9%,Cu 1.8%~2.1%,Mg 1.3%~1.4%,Ti 0.02%~0.08%,Ni 0.7%~0.9%,0.1%≤Mn+Cr+Zr≤0.2%;single impurity≤0.05%,total impurities≤0.1%,the remainder is Al, totaling 100%.

[0007] Furthermore, the diameter of the aluminum alloy rod is 20 to 80 mm.

[0008] According to a second aspect of the present invention, there is provided a method for preparing an Al-Cu-Mg-Fe-Ni aluminum alloy rod, comprising hot extruding an Al-Cu-Mg-Fe-Ni aluminum alloy ingot to obtain an extruded rod:

[0009] Among them, during the hot extrusion process, the heating temperature of the head of the aluminum alloy ingot is greater than the heating temperature of the tail;

[0010] The extrusion speed of the front section of the aluminum alloy ingot is greater than the extrusion speed of the rear section;

[0011] The Al-Cu-Mg-Fe-Ni aluminum alloy ingot is an ingot prepared by using the proportions of the components of the above-mentioned Al-Cu-Mg-Fe-Ni aluminum alloy rod, or an ingot prepared by using the proportions of the components of the aluminum alloy rod of grade 2A70 or grade 2D70.

[0012] Furthermore, the Al-Cu-Mg-Fe-Ni aluminum alloy ingot is a heat-treated ingot, specifically comprising:

[0013] The aluminum alloy ingot is obtained by smelting according to the proportion of each component in the aluminum alloy rod; and the aluminum alloy ingot is subjected to homogenization heat treatment to obtain a heat-treated ingot.

[0014] Furthermore, the method for preparing the Al-Cu-Mg-Fe-Ni aluminum alloy bar further comprises the following steps after the hot extrusion process:

[0015] The extruded rod is subjected to solution heat treatment to obtain a solution heat treated rod; the solution heat treated rod is stretched and straightened to obtain a stretched and straightened rod; and the stretched and straightened rod is subjected to aging heat treatment to obtain an Al-Cu-Mg-Fe-Ni aluminum alloy rod.

[0016] Furthermore, during the hot extrusion process, the heating temperature of the head of the aluminum alloy ingot is 5 to 20° C. higher than the heating temperature of the tail of the aluminum alloy ingot.

[0017] Furthermore, the heating temperature of the head of the aluminum alloy ingot is 430°C to 440°C, and the heating temperature of the tail of the aluminum alloy ingot is 420°C to 430°C.

[0018] Furthermore, the heating temperature of the hot extrusion die is 400°C to 420°C, and the heating temperature of the extrusion barrel in the die is 400°C to 420°C.

[0019] Furthermore, during the hot extrusion process, 1 / 2 of the length of the aluminum alloy ingot near the head is the front section, and 1 / 2 of the length of the aluminum alloy ingot near the tail is the rear section.

[0020] Furthermore, the extrusion speed of the front section is 1.5-2.0 mm / s, and the extrusion speed of the rear section is 0.5-1.0 mm / s.

[0021] Further, the solution heat treatment includes a first solution heat treatment and a second solution heat treatment;

[0022] The first solution heat treatment process includes: a heating rate of 90°C / h to 160°C / h, a temperature of 440°C to 460°C, and a holding time of 0.5h to 1.0h;

[0023] The second solution heat treatment process includes: a heating rate of 500°C / h to 1000°C / h, a temperature of 530°C to 540°C, and a holding time of 1.5h to 2.5h.

[0024] Furthermore, the hot extrusion die is a flat die; the working band length of the die is 2 to 3 mm.

[0025] Furthermore, during the stretching and straightening process, the stretching and straightening amount is ≤2.0%.

[0026] Furthermore, the temperature of the aging heat treatment is 195° C. to 205° C., and the holding time of the aging heat treatment is 8 h to 12 h.

[0027] According to a third aspect of the present invention, there is provided application of the Al-Cu-Mg-Fe-Ni aluminum alloy rod or the Al-Cu-Mg-Fe-Ni aluminum alloy rod obtained by the above preparation method in aviation materials.

[0028] By applying the technical scheme of the present invention, an Al-Cu-Mg-Fe-Ni aluminum alloy bar and a preparation method thereof are provided. By adding trace elements Mn, Cr and Zr into the alloy ingredients, recrystallization growth can be suppressed, the crystallization ratio can be effectively adjusted, and the grains can be uniform. By optimizing the extrusion process, such as the head extrusion temperature is greater than the tail extrusion temperature, such as the front section extrusion speed is greater than the middle section extrusion speed is greater than the rear section extrusion speed, and by regulating the deformation energy storage during the extrusion process, the nucleation rate and the growth rate of the crystal nucleus are reduced, the grains are fine and uniform, and the use requirements of the grains are met. By using a two-stage solid solution system, the tensile strength is ≥355MPa and the elongation is ≥8%. The Al-Cu-Mg-Fe-Ni aluminum alloy extrusion process of the present invention is not only applicable to 2A70 and 2D70 alloys, but can also be extended to other Al-Cu-Mg-Fe-Ni series heat-resistant aluminum alloys. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0030] Figure 1 The macrostructure diagram of the aluminum alloy extruded rod prepared in Example 1 of the present invention is shown;

[0031] Figure 2 The macrostructure diagram of the aluminum alloy extruded rod prepared in Example 2 of the present invention is shown;

[0032] Figure 3 The macrostructure diagram of the aluminum alloy extruded bar prepared in Comparative Example 1 of the present invention is shown;

[0033] Figure 4 A high-power microscopic image of the aluminum alloy extruded bar prepared in Example 1 of the present invention is shown;

[0034] Figure 5 A high-power microscopic image of the aluminum alloy extruded rod prepared in Example 2 of the present invention is shown;

[0035] Figure 6 A high-power microscopic image of the aluminum alloy extruded rod prepared in Comparative Example 1 of the present invention is shown. DETAILED DESCRIPTION

[0036] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0037] The present invention provides an Al-Cu-Mg-Fe-Ni aluminum alloy bar, comprising the following components in weight percentage:

[0038] Si≤0.02,Fe 0.7%~0.9%,Cu 1.8%~2.1%,Mg 1.3%~1.4%,Ti 0.02%~0.08%,Ni 0.7%~0.9%,0.1%≤Mn+Cr+Zr≤0.2%;single impurity≤0.05%,total impurities≤0.1%,the remainder is Al, totaling 100%.

[0039] The invention discloses a novel aluminum alloy bar material provided by the present invention. The three trace elements Mn, Cr and Zr are added to inhibit the recrystallization of grains in the aluminum alloy. The addition ratio of Mn, Cr and Zr is adjusted to make 0.1%≤Mn+Cr+Zr≤0.2%. The growth of recrystallization can be inhibited and the recrystallization ratio can be effectively adjusted to make the grain size uniform. The main elements in the material are Fe0.7%-0.9%, Cu 1.8%-2.1%, Mg 1.3%-1.4%, Ni 0.7%-0.9% and the balance Al. The mechanical properties and heat resistance of the aluminum alloy can be improved by adjusting the ratio of these main elements. The novel aluminum alloy bar material has a tensile strength of ≥355MPa and an elongation of ≥8.0%, and has good mechanical properties.

[0040] As a specific implementation, the diameter of the aluminum alloy rod is 20 to 80 mm.

[0041] According to a second aspect of the present invention, there is provided a method for preparing an Al-Cu-Mg-Fe-Ni aluminum alloy rod, comprising hot extruding an Al-Cu-Mg-Fe-Ni aluminum alloy ingot to obtain an extruded rod:

[0042] Among them, during the hot extrusion process, the heating temperature of the head of the aluminum alloy ingot is greater than the heating temperature of the tail;

[0043] The extrusion speed of the front section of the aluminum alloy ingot is greater than the extrusion speed of the rear section;

[0044] The Al-Cu-Mg-Fe-Ni aluminum alloy ingot is an ingot prepared by using the proportions of the components of the above-mentioned Al-Cu-Mg-Fe-Ni aluminum alloy rod, or an ingot prepared by using the proportions of the components of the aluminum alloy rod of grade 2A70 or grade 2D70.

[0045] The present invention optimizes the extrusion process and regulates the deformation energy storage during the extrusion process, so that the nucleation rate and growth rate of the crystal nucleus are reduced, the crystal grains are fine and uniform, and the requirements for the use of the crystal grains are met; the tensile strength is ≥355MPa, and the elongation is ≥8.0%.

[0046] The present invention finds that in the extrusion process, the head of the aluminum alloy ingot is extruded first and cools down faster in the environment, and the tail is extruded later, and the tail will generate heat due to extrusion during the continuous extrusion process, which causes the temperature of the aluminum alloy material that comes out first to be lower than that of the aluminum alloy material that comes out later, thereby producing a relatively obvious temperature difference, and this temperature difference will cause the same aluminum alloy bar to have different deformation energy storage due to uneven internal heat distribution and uneven grain crystallization; in order to overcome the extrusion defect, it is designed to increase the hot extrusion temperature of the ingot head, so that the hot extrusion temperature of the head is slightly higher than the hot pressing temperature of the tail, so that the temperature of the head after hot extrusion can be similar to or the same as the temperature of the tail that is being extruded but not yet out, thereby minimizing the temperature difference in the same aluminum alloy material and improving the uniformity of grain crystallization and mechanical properties; and in order to overcome the extrusion temperature difference, in addition to improving the temperature of the head and tail of the aluminum alloy material, the extrusion speed of each part of the aluminum alloy is also optimized. For the same reason, when a single When the extrusion speed is high, the head aluminum alloy extruded first cools down faster in the environment. At the same time, the middle part and the rear part being extruded in the heating cylinder are being extruded, that is, they are continuously generating heat. This will cause a temperature difference between the first extruded part and the later extruded part of the aluminum alloy. This phenomenon is not conducive to the uniformity and fineness of grain crystallization. For this reason, the present invention is designed to make the extrusion speed of the front part of the aluminum alloy slightly greater than the extrusion speed of the rear part. By adopting different extrusion speeds and the extrusion speed of the front part that comes out first is larger, and the extrusion speed of the later part that comes out last is smaller, because the faster the extrusion speed, the aluminum alloy generates more heat due to the extrusion friction, which can compensate for the phenomenon of cooling of the first aluminum alloy material. By adopting two different extrusion speeds, the products of each extrusion speed are continuously matched, so that the temperatures of the two sections of aluminum alloy can be similar or the same during the extrusion process, avoiding the generation of temperature, thereby improving the crystallinity, uniformity, fineness of the grains and improving the mechanical properties of the aluminum alloy.

[0047] As a specific implementation manner, the Al-Cu-Mg-Fe-Ni aluminum alloy ingot is a heat-treated ingot, specifically comprising:

[0048] The aluminum alloy ingot is obtained by smelting according to the proportion of each component in the aluminum alloy rod; and the aluminum alloy ingot is subjected to homogenization heat treatment to obtain a heat-treated ingot.

[0049] In step S1 of the present invention, the above-mentioned novel aluminum alloy bar material is used to prepare aluminum alloy ingots. By adding three trace elements of Mn, Cr and Zr, the recrystallization of grains in the aluminum alloy can be suppressed. By adjusting the addition ratio of Mn, Cr and Zr, 0.1%≤Mn+Cr+Zr≤0.2% can be made; not only can the growth of recrystallization be suppressed, but also the proportion of recrystallization can be effectively adjusted to make the grain size uniform; Fe 0.7%~0.9%, Cu 1.8%~2.1%, Mg 1.3%~1.4%, Ni 0.7%~0.9% and the remaining Al are the main elements in the material, and the proportion of these main elements is adjusted. The tensile strength of the above-mentioned novel aluminum alloy bar of the present invention is ≥355MPa, and the elongation is ≥8.0%, and it has good mechanical properties; it can improve the mechanical properties and heat resistance of the aluminum alloy. The internal structure of the metal is improved by homogenization heat treatment, casting stress is eliminated, segregation is reduced, and it is more conducive to the subsequent stretching and extrusion processes.

[0050] As a specific implementation manner, the method for preparing the Al-Cu-Mg-Fe-Ni aluminum alloy bar further includes the following steps after the hot extrusion process:

[0051] performing a solution heat treatment on the extruded rod to obtain a solution heat treated rod;

[0052] The solution heat treated rod is stretched and straightened to obtain a stretch-straightened rod;

[0053] The stretched and straightened rod is subjected to aging heat treatment to obtain Al-Cu-Mg-Fe-Ni aluminum alloy rod.

[0054] The present invention prepares the aluminum alloy rod by hot extrusion, and then improves the grain morphology in the rod by solid solution heat treatment to ensure that the solid solution of the alloy is fully dissolved into the matrix, thereby ensuring the mechanical properties of the alloy. The obtained aluminum alloy rod has a tensile strength of ≥355MPa and an elongation of ≥8.0%.

[0055] As a preferred embodiment, during the hot extrusion process, the heating temperature of the head of the aluminum alloy ingot is 5 to 20°C higher than the heating temperature of the tail of the aluminum alloy ingot. When the difference between the head hot pressing temperature and the tail hot extrusion temperature is controlled at 5 to 20°C, the temperature of the first extruded head and the temperature of the later extruded tail can be appropriately adjusted to achieve almost the same effect, which can reduce the deformation energy storage during the extrusion process and improve the uniformity of the head and tail of the extruded bar, so that the grains are further refined and uniform; this ensures that each part of the same aluminum alloy bar has the same or similar heating temperature or internal heat, which can promote the internal crystallization of the aluminum alloy to be more refined and uniform, and is more conducive to the improvement of the mechanical properties of the final product.

[0056] As a preferred embodiment, the heating temperature of the hot extrusion die is 400°C to 420°C, and the heating temperature of the extrusion barrel in the die is 400°C to 420°C. In the present invention, the heating temperature of the hot extrusion die and the extrusion barrel temperature are the same or similar, and the temperature can be adjusted according to the characteristics of the aluminum alloy components, and cannot be too high or too low, so as to avoid that the hot extrusion effect cannot be achieved if it is too low, and the extrusion quality will be affected if it is too high.

[0057] As a preferred embodiment, the head heating temperature of the aluminum alloy ingot is 430°C to 440°C, and the tail heating temperature of the aluminum alloy ingot is 420°C to 430°C. For example, the head heating temperature is 430°C, the tail heating temperature is 420°C, or the head heating temperature is 440°C, the tail heating temperature is 420°C, or the head heating temperature is 440°C, the tail heating temperature is 430°C, etc. In the present invention, within a large hot extrusion range, the head temperature is increased to above 430°C, and the tail temperature is controlled to be above 420°C. The head temperature is always greater than the tail temperature. In this way, during the extrusion process, the head and tail temperatures are similar or the same, which can balance the overall temperature of the same aluminum alloy material, reduce the temperature difference during the hot extrusion process, further improve the crystallization performance of the aluminum alloy grains, make them finer and more uniform, and also promote the mechanical properties of the aluminum alloy.

[0058] As a preferred embodiment, during the hot extrusion process, the 1 / 2 length of the aluminum alloy ingot near the head is the front section, and the 1 / 2 length of the aluminum alloy ingot near the tail is the rear section. The present invention divides the aluminum alloy into two sections on average, which are called the front section and the rear section in the order of being hot extruded first and last, and accurately controls the different extrusion speeds of the two sections. The present invention can further accurately measure the heat generated by each section during the extrusion process through different extrusion speeds in accordance with the average segmentation method, so as to facilitate the homogenization, refinement and uniform mechanical properties of the aluminum alloy grains.

[0059] As a preferred embodiment, the extrusion speed of the front section is 1.5-2.0 mm / s, and the extrusion speed of the rear section is 0.5-1.0 mm / s. According to the heat generated by the extrusion friction of the aluminum alloy during the extrusion process and the hot extrusion temperature and the dissolution or dissolution of metal elements in the aluminum matrix, the present invention appropriately designs two sections of different extrusion speeds to balance the same or similar heat in each section during the extrusion process and avoid the phenomenon of metal elements dissolving from the aluminum matrix; the present invention designs the extrusion speed of the front section and the rear section in a gradient progressive mode, the extrusion speed of the front section is 1.5-2.0 mm / s faster, and the rear section is controlled at 0.5-1.0 mm / s. Such a gradient extrusion speed can balance the heat in the aluminum alloy during the extrusion process, reduce the temperature difference, and can also avoid the dissolution of metal components from the aluminum matrix as much as possible, further promoting the crystallization effect and mechanical properties of the aluminum alloy.

[0060] As a preferred embodiment, the solution heat treatment includes a first solution heat treatment and a second solution heat treatment; the process of the first solution heat treatment includes: a heating rate of 90℃ / h~160℃ / h, a temperature of 440℃~460℃, and a holding time of 0.5h~1.0h; the process of the second solution heat treatment includes: a heating rate of 500℃ / h~1000℃ / h, a temperature of 530℃~540℃, and a holding time of 1.5h~2.5h.

[0061] The present invention adopts a two-stage solid solution system. The first stage solid solution system can adjust the grain morphology. The second stage solid solution system ensures that the solid solution of the alloy is fully dissolved into the matrix under the premise that the grain morphology meets the requirements, thereby ensuring the mechanical properties of the alloy.

[0062] As a specific implementation manner, the present invention stretches and straightens the aluminum alloy after the solid solution heat treatment, and the stretching and straightening amount is ≤2.0%.

[0063] As a specific implementation method, the temperature of the aging heat treatment is 195°C to 205°C, and the holding time of the aging heat treatment is 8h to 12h. The present invention can eliminate internal stress, stabilize the organization and structure of the aluminum alloy bar, and improve its mechanical properties by adopting the artificial aging treatment at the above temperature and time. For example, the tensile strength of the aluminum alloy bar of the present invention is ≥355MPa, and the elongation is ≥8.0%.

[0064] As a more specific embodiment, the present invention provides a method for preparing an Al-Cu-Mg-Fe-Ni aluminum alloy extruded bar with uniform fine grain structure, comprising the following steps:

[0065] (1) subjecting the prepared aluminum alloy round ingot to homogenization heat treatment to obtain an aluminum alloy round ingot after homogenization heat treatment;

[0066] (2) milling the aluminum alloy round ingot obtained in step (1) and then subjecting it to induction heating, wherein the heating temperature of the head end of the round ingot is 430° C. to 440° C., and the heating temperature of the tail end is 420° C. to 430° C., and the heating temperature of the tail end is 10° C. to 20° C. lower than that of the head end;

[0067] (3) The die structure is a flat die with a working band length of 2 to 3 mm. The die is heated to 400° C. to 420° C., the extrusion barrel is heated to 400° C. to 420° C., the extrusion pad is cooled by liquid nitrogen, and then the aluminum alloy ingot treated in step (2) is placed therein. The extrusion speed of the first 1 / 2 length of the ingot is 1.5 to 2.0 mm / s, and the extrusion speed of the rear 1 / 2 length is 0.5 to 1.0 mm / s, to obtain an aluminum alloy rod;

[0068] (4) The aluminum alloy rod obtained in step (3) is subjected to a solution heat treatment, wherein the solution heat treatment system is as follows: a heating rate of 90°C / h to 160°C / h, a temperature of 440°C to 460°C, and a holding time of 0.5h to 1.0h; a second-stage solution heating rate of 500°C / h to 1000°C / h, a temperature of 530°C to 540°C, and a holding time of 1.5h to 2.5h.

[0069] (5) stretching and straightening the rod treated in step (4), wherein the stretching and straightening amount is ≤2.0%;

[0070] (6) The aluminum alloy bar after stretching and straightening in step (5) is subjected to artificial aging heat treatment, the artificial aging heat treatment temperature is 195° C. to 205° C., and the holding time is 8 h to 12 h, so as to obtain an Al-Cu-Mg-Fe-Ni aluminum alloy extruded bar with uniform fine grain structure.

[0071] The Al-Cu-Mg-Fe-Ni aluminum alloy rod provided by the present invention or the Al-Cu-Mg-Fe-Ni aluminum alloy rod obtained by the above preparation method has finer grains, uniform grain distribution, tensile strength ≥355MPa, elongation ≥8.0%, good heat resistance, and can be well applied to aviation materials.

[0072] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0073] Example 1

[0074] A method for preparing an Al-Cu-Mg-Fe-Ni aluminum alloy extruded bar comprises the following steps:

[0075] The ingredients are prepared according to the weight percentage of each component in the aluminum alloy bar: Si 0.01%, Fe 0.7%, Cu1.8%, Mg 1.3%, Ti 0.02%, Ni 0.7%, Mn 0.06%, Cr 0.04%, Zr 0.06%, single impurity ≤ 0.05%, total impurity ≤ 0.15%, the balance is Al, a total of 100%;

[0076] Aluminum ingots, Mg ingots, Al-Cu master alloys, Fe-Ni alloys, Al-Mn alloys, Al-Cr alloys, Al-Zr alloys, etc. are melted to obtain aluminum alloy round ingots. The round ingots are homogenized and heat treated before extrusion. The extrusion die structure is a flat die with a working band length of 2 mm. The extrusion process is as follows: electromagnetic heating of the head end temperature of the round ingot to 430°C, the tail end temperature to 420°C, the extrusion barrel temperature to 400°C, the extrusion die temperature to 400°C, liquid nitrogen cooling of the extrusion pad, the extrusion speed of the front 1 / 2 length of the round ingot is 1.5 mm / s, and the extrusion speed of the rear 1 / 2 length is 0.5 mm / s to obtain extruded bars. The obtained extruded rods were subjected to solution heat treatment, and the solution system was as follows: the first-stage solution heating rate was 90°C / h, the solution temperature was 440°C, and the holding time was 0.5h; the second-stage solution heating rate was 1000°C / h, the solution temperature was 530°C, and the holding time was 1.5h. After the solution heat treatment, the rods were water-cooled to room temperature; the rods after the solution heat treatment were stretched and straightened, and the stretching straightening amount was ≤2.0%; the straightened extruded rods were subjected to artificial aging heat treatment, the artificial aging temperature was 195°C, the holding time was 8h, and they were cooled to room temperature. The cooling medium was air, and Al-Cu-Mg-Fe-Ni aluminum alloy extruded rods were obtained, and their macrostructure was as follows Figure 1 As shown, the high-magnification tissue structure is Figure 4 The test results of the microstructure and properties of the extruded rods are shown in Table 1.

[0077] Example 2

[0078] A method for preparing an Al-Cu-Mg-Fe-Ni aluminum alloy extruded bar comprises the following steps:

[0079] Si 0.01%, Fe 0.8%, Cu 1.9%, Mg 1.4%, Ti 0.06%, Ni 0.8%, Mn 0.04%, Cr0.03%, Zr 0.05%, single impurity ≤ 0.05%, total impurity ≤ 0.15%, the balance is Al, a total of 100%;

[0080] Aluminum ingots, Mg ingots, Al-Cu master alloys, Fe-Ni alloys, Al-Mn alloys, Al-Cr alloys, Al-Zr alloys, etc. are melted to obtain aluminum alloy round ingots. The round ingots are homogenized and heat treated before extrusion. The extrusion die structure is a flat die with a working band length of 3 mm. The extrusion process is as follows: electromagnetic heating of the head end temperature of the round ingot to 435°C, the tail end temperature to 430°C, the extrusion barrel temperature to 410°C, the extrusion die temperature to 410°C, liquid nitrogen cooling of the extrusion pad, the extrusion speed of the front 1 / 2 length of the round ingot is 1.75 mm / s, and the extrusion speed of the rear 1 / 2 length is 0.75 mm / s to obtain extruded bars. The obtained extruded rods were subjected to solution heat treatment, and the solution system was as follows: the first-stage solution heating rate was 125°C / h, the solution temperature was 450°C, and the holding time was 1h; the second-stage solution heating rate was 750°C / h, the solution temperature was 535°C, and the holding time was 2h. After the solution heat treatment, the rods were water-cooled to room temperature; the rods after the solution heat treatment were stretched and straightened, and the stretching straightening amount was ≤2.0%; the straightened extruded rods were subjected to artificial aging heat treatment, the artificial aging temperature was 200°C, the holding time was 10h, and they were cooled to room temperature. The cooling medium was air, and Al-Cu-Mg-Fe-Ni aluminum alloy extruded rods were obtained, and their macrostructure was as follows Figure 1 As shown, the high-magnification tissue structure is Figure 4 The test results of the microstructure and properties of the extruded rods are shown in Table 1.

[0081] Example 3

[0082] Si 0.01%, Fe 0.9%, Cu 2.1%, Mg 1.35%, Ti 0.08%, Ni 0.9%, Mn 0.03%, Cr0.025%, Zr 0.045%, single impurity ≤ 0.05%, total impurity ≤ 0.15%, the balance is Al, a total of 100%;

[0083] Aluminum ingots, Mg ingots, Al-Cu master alloys, Fe-Ni alloys, Al-Mn alloys, Al-Cr alloys, Al-Zr alloys, etc. are melted to obtain aluminum alloy round ingots. The round ingots are homogenized and heat treated before extrusion. The extrusion die structure is a flat die with a working band length of 2.5 mm. The extrusion process is as follows: electromagnetic heating of the head end temperature of the round ingot to 440°C, the tail end temperature to 425°C, the extrusion barrel temperature to 420°C, the extrusion die temperature to 420°C, liquid nitrogen cooling of the extrusion pad, the extrusion speed of the front 1 / 2 length of the round ingot is 2 mm / s, and the extrusion speed of the rear 1 / 2 length is 1 mm / s to obtain extruded bars. The obtained extruded rods were subjected to solution heat treatment, and the solution system was as follows: the first-stage solution heating rate was 160°C / h, the solution temperature was 460°C, and the holding time was 0.5h; the second-stage solution heating rate was 500°C / h, the solution temperature was 540°C, and the holding time was 2.5h. After solution heat treatment, the rods were water-cooled to room temperature; the rods after solution heat treatment were stretched and straightened, and the stretching straightening amount was ≤2.0%; the straightened extruded rods were subjected to artificial aging heat treatment, the artificial aging temperature was 205°C, the holding time was 12h, and they were cooled to room temperature. The cooling medium was air, and the Al-Cu-Mg-Fe-Ni aluminum alloy extruded rods were obtained. The test results of the microstructure and properties of the extruded rods are shown in Table 1.

[0084] Example 4

[0085] Si 0.01%, Fe 0.7%, Cu 1.9%, Mg 1.3%, Ti 0.02%, Ni 0.7%, Mn 0.08%, Cr0.05%, Zr 0.07%, individual impurities ≤ 0.05%, total impurities ≤ 0.15%, the balance is Al, a total of 100%;

[0086] Aluminum ingots, Mg ingots, Al-Cu master alloys, Fe-Ni alloys, Al-Mn alloys, Al-Cr alloys, Al-Zr alloys, etc. are melted to obtain aluminum alloy round ingots. The round ingots are homogenized and heat treated before extrusion. The extrusion die structure is a flat die with a working band length of 3 mm. The extrusion process is as follows: electromagnetic heating of the head end temperature of the round ingot to 430°C, the tail end temperature to 425°C, the extrusion barrel temperature to 415°C, the extrusion die temperature to 415°C, liquid nitrogen cooling of the extrusion pad, the extrusion speed of the front 1 / 2 length of the round ingot is 1.5 mm / s, and the extrusion speed of the rear 1 / 2 length is 0.5 mm / s to obtain extruded bars. The obtained extruded rods were subjected to solution heat treatment, and the solution system was as follows: the first-stage solution heating rate was 125°C / h, the solution temperature was 445°C, and the holding time was 1h; the second-stage solution heating rate was 500°C / h, the solution temperature was 530°C, and the holding time was 2.5h. After solution heat treatment, the rods were water-cooled to room temperature; the rods after solution heat treatment were stretched and straightened, and the stretching straightening amount was ≤2.0%; the straightened extruded rods were subjected to artificial aging heat treatment, the artificial aging temperature was 195°C, the holding time was 8h, and they were cooled to room temperature. The cooling medium was air, and Al-Cu-Mg-Fe-Ni aluminum alloy extruded rods were obtained. The test results of the microstructure and properties of the obtained extruded rods are shown in Table 1.

[0087] Example 5

[0088] Si 0.01%, Fe 0.7%, Cu 1.9%, Mg 1.3%, Ti 0.02%, Ni 0.9%, Mn 0.06%, Cr 0.04%, Zr 0.06%, single impurity ≤ 0.05%, total impurity ≤ 0.15%, the balance is Al, a total of 100%;

[0089] Aluminum ingots, Mg ingots, Al-Cu master alloys, Fe-Ni alloys, Al-Mn alloys, Al-Cr alloys, Al-Zr alloys, etc. are melted to obtain aluminum alloy round ingots. The round ingots are homogenized and heat treated before extrusion. The extrusion die structure is a flat die with a working band length of 2.5 mm. The extrusion process is as follows: electromagnetic heating of the head end temperature of the round ingot to 435°C, the tail end temperature to 420°C, the extrusion barrel temperature to 415°C, the extrusion die temperature to 415°C, liquid nitrogen cooling of the extrusion pad, the extrusion speed of the front 1 / 2 length of the round ingot is 2 mm / s, and the extrusion speed of the rear 1 / 2 length is 0.5 mm / s to obtain extruded bars. The obtained extruded rods were subjected to solution heat treatment, and the solution system was as follows: the first-stage solution heating rate was 125°C / h, the solution temperature was 450°C, and the holding time was 1h; the second-stage solution heating rate was 500°C / h, the solution temperature was 535°C, and the holding time was 2h. After solution heat treatment, the rods were water-cooled to room temperature; the rods after solution heat treatment were stretched and straightened, and the stretching straightening amount was ≤2.0%; the straightened extruded rods were subjected to artificial aging heat treatment, the artificial aging temperature was 195°C, the holding time was 12h, and they were cooled to room temperature. The cooling medium was air, and Al-Cu-Mg-Fe-Ni aluminum alloy extruded rods were obtained. The test results of the microstructure and properties of the obtained extruded rods are shown in Table 1.

[0090] Example 6

[0091] Si 0.01%, Fe 0.9%, Cu 2.1%, Mg 1.5%, Ti 0.08%, Ni 0.8%, Mn 0.08%, Cr0.05%, Zr 0.07%, single impurity ≤ 0.05%, total impurity ≤ 0.15%, the balance is Al, a total of 100%;

[0092] Aluminum ingots, Mg ingots, Al-Cu master alloys, Fe-Ni alloys, Al-Mn alloys, Al-Cr alloys, Al-Zr alloys, etc. are melted to obtain aluminum alloy round ingots. The round ingots are homogenized and heat treated before extrusion. The extrusion die structure is a flat die with a working band length of 2 mm. The extrusion process is as follows: electromagnetic heating of the head end temperature of the round ingot to 440°C, the tail end temperature to 430°C, the extrusion barrel temperature to 405°C, the extrusion die temperature to 405°C, liquid nitrogen cooling of the extrusion pad, the extrusion speed of the front 1 / 2 length of the round ingot is 1.75 mm / s, and the extrusion speed of the rear 1 / 2 length is 1 mm / s to obtain extruded bars. The obtained extruded rods were subjected to solution heat treatment, and the solution system was as follows: the first-stage solution heating rate was 135°C / h, the solution temperature was 455°C, and the holding time was 0.5h; the second-stage solution heating rate was 750°C / h, the solution temperature was 533°C, and the holding time was 1h. After solution heat treatment, the rods were water-cooled to room temperature; the rods after solution heat treatment were stretched and straightened, and the stretching straightening amount was ≤2.0%; the straightened extruded rods were subjected to artificial aging heat treatment, the artificial aging temperature was 205°C, the holding time was 8h, and they were cooled to room temperature. The cooling medium was air, and Al-Cu-Mg-Fe-Ni aluminum alloy extruded rods were obtained. The test results of the microstructure and properties of the obtained extruded rods are shown in Table 1.

[0093] Comparative Example 1

[0094] A method for preparing an Al-Cu-Mg-Fe-Ni aluminum alloy extruded bar comprises the following steps:

[0095] The ingredients are formulated according to the weight percentage of each component in the aluminum alloy bar: Si 0.01%, Fe 0.7%, Cu1.8%, Mg 1.3%, Ti 0.02%, Ni 0.7%, Cr 0.2%, single impurity ≤0.05%, total impurity ≤0.15%, and the rest is Al.

[0096] Aluminum ingots, Mg ingots, Al-Cu master alloys, Fe-Ni alloys, Al-Cr alloys, etc. are melted to obtain aluminum alloy round ingots. The round ingots are homogenized and heat treated before extrusion. The extrusion die structure is a flat die with a working band length of 2 mm. The extrusion process is as follows: electromagnetic heating of the head end temperature of the round ingot to 440°C, the tail end temperature to 420°C, the extrusion barrel temperature to 380°C, the extrusion die temperature to 380°C, liquid nitrogen cooling of the extrusion pad, the extrusion speed of the front 1 / 2 length of the round ingot is 1.5 mm / s, and the extrusion speed of the rear 1 / 2 length is 0.5 mm / s to obtain extruded bars. The obtained extruded rods were subjected to solution heat treatment, and the solution system was as follows: the first-stage solution heating rate was 455°C / h, the solution temperature was 400°C, and the holding time was 1h; the second-stage solution heating rate was 1000°C / h, the solution temperature was 538°C, and the holding time was 2h. After the solution heat treatment, the rods were water-cooled to room temperature; the rods after the solution heat treatment were stretched and straightened, and the stretching straightening amount was ≤2.0%; the straightened extruded rods were subjected to artificial aging heat treatment, and the artificial aging temperature was 205°C, the holding time was 8h, and cooled to room temperature. The cooling medium was air, and Al-Cu-Mg-Fe-Ni aluminum alloy extruded rods were obtained, and their macrostructure was as follows Figure 3 As shown, the high-magnification tissue structure is Figure 6 The test results of the microstructure and properties of the extruded rods are shown in Table 1.

[0097] Comparative Example 2

[0098] A method for preparing an Al-Cu-Mg-Fe-Ni aluminum alloy extruded bar comprises the following steps:

[0099] The ingredients are prepared according to the weight percentage of each component in the aluminum alloy bar: Si 0.01%, Fe 0.8%, Cu1.9%, Mg 1.75%, Ti 0.06%, Ni 0.8%, Mn 0.18%, Cr 0.1%, Zr 0.12%, single impurity ≤0.05%, total impurity ≤0.15%, and the rest is Al.

[0100] Aluminum ingots, Mg ingots, Al-Cu master alloys, Fe-Ni alloys, Al-Mn alloys, Al-Cr alloys, Al-Zr alloys, etc. are melted to obtain aluminum alloy round ingots. The round ingots are homogenized and heat treated before extrusion. The extrusion die structure is a flat die with a working band length of 5 mm. The extrusion process is as follows: electromagnetic heating of the head end temperature of the round ingot to 450°C, the tail end temperature to 440°C, the extrusion barrel temperature to 390°C, the extrusion die temperature to 390°C, liquid nitrogen cooling of the extrusion pad, the extrusion speed of the front 1 / 2 length of the round ingot is 1mm / s, and the extrusion speed of the rear 1 / 2 length is 1.5mm / s to obtain extruded bars. The obtained extruded rods were subjected to solution heat treatment, and the solution system was as follows: the first-stage solution heating rate was 1000℃ / h, the solution temperature was 480℃, and the holding time was 2h; the second-stage solution heating rate was 1000℃ / h, the solution temperature was 520℃, and the holding time was 3h. After solution heat treatment, the rods were water-cooled to room temperature; the rods after solution heat treatment were stretched and straightened, and the stretching straightening amount was ≤2.0%; the straightened extruded rods were subjected to artificial aging heat treatment, the artificial aging temperature was 170℃, the holding time was 12h, and they were cooled to room temperature. The cooling medium was air, and Al-Cu-Mg-Fe-Ni aluminum alloy extruded rods were obtained. The test results of the microstructure and properties of the obtained extruded rods are shown in Table 1.

[0101] Comparative Example 3

[0102] A method for preparing an Al-Cu-Mg-Fe-Ni aluminum alloy extruded bar comprises the following steps:

[0103] The ingredients are prepared according to the weight percentage of each component in the aluminum alloy bar: Si 0.01%, Fe 0.9%, Cu2.1%, Mg 1.5%, Ti 0.08%, Ni 0.9%, Mn 0.06%, Cr 0.04%, Zr 0.06%, single impurity ≤0.05%, total impurity ≤0.15%, and the rest is Al.

[0104] Aluminum ingots, Mg ingots, Al-Cu master alloys, Fe-Ni alloys, Al-Mn alloys, Al-Cr alloys, Al-Zr alloys, etc. are melted to obtain aluminum alloy round ingots. The round ingots are homogenized and heat treated before extrusion. The extrusion die structure is a flat die with a working belt length of 6 mm. The extrusion process is as follows: electromagnetic heating of the round ingot temperature is 400°C, the extrusion barrel temperature is 400°C, the extrusion die temperature is 400°C, the extrusion pad is cooled by liquid nitrogen, the extrusion speed of the front 1 / 2 length of the round ingot is 1mm / s, and the extrusion speed of the rear 1 / 2 length is 1.5mm / s to obtain extruded bars. The obtained extruded rods were subjected to solution heat treatment, and the solution system was as follows: the first-stage solution heating rate was 160°C / h, the solution temperature was 420°C, and the holding time was 3h; the second-stage solution heating rate was 340°C / h, the solution temperature was 545°C, and the holding time was 6h. After solution heat treatment, the rods were water-cooled to room temperature; the rods after solution heat treatment were stretched and straightened, and the stretching straightening amount was ≤2.0%; the straightened extruded rods were subjected to artificial aging heat treatment, the artificial aging temperature was 200°C, the holding time was 14h, and they were cooled to room temperature. The cooling medium was air, and Al-Cu-Mg-Fe-Ni aluminum alloy extruded rods were obtained. The test results of the microstructure and properties of the obtained extruded rods are shown in Table 1.

[0105] Table 1 Test results of the microstructure and properties of the extruded rods obtained in Examples 1 to 6 and Comparative Examples 1 to 3

[0106]

[0107]

[0108] The test results in Table 1 show that the Al-Cu-Mg-Fe-Ni aluminum alloy bars prepared in Examples 1 to 6 of the present invention have finer grains, more uniform grain distribution, tensile strength ≥ 355MPa (375 to 432MPa), and elongation ≥ 8.0% (8.5 to 15.8%); the grains of Comparative Examples 1 to 3 are coarse and / or unevenly distributed, with a tensile strength of 320 to 345MPa and an elongation of about 10.5 to 15.9. By comparison, it can be seen that the tensile strength of the aluminum alloy bars of the present invention is 30 to 90MPa higher than that of the aluminum alloy bars of Comparative Examples 1 to 3, and the mechanical properties of the aluminum alloy bars prepared in the embodiments of the present invention are significantly better than those of the aluminum alloy bars prepared in Comparative Examples 1 to 3.

[0109] The internal structure detection graphs of the aluminum alloy bars prepared in various embodiments and comparative examples show that, at the same scanning magnification, Figures 1-2 and Figure 3 In contrast, the cross-section of the aluminum alloy bars of Examples 1 to 2 of the present invention has finer grains and a more uniform grain distribution, while the cross-section of the bars of Comparative Examples 1 to 3 is rough, the grains are of different sizes, and the grain distribution is also uneven; Figures 4-5 and Figure 6In contrast, the embodiment of the present invention Figures 4-5 The metal grain size in the center and edge of the rod is obviously smaller and more evenly distributed. Figure 6 The metal grains in the center and edge of the middle bar are relatively larger and unevenly distributed.

[0110] The trace elements introduced into the aluminum alloy bar material of comparative example 1 are only Cr 0.2%, while the trace elements introduced into the aluminum alloy bar material of embodiments 1-2 of the present invention are 0.1%≤Mn+Cr+Zr≤0.2%. From the performance and internal structure test results of the two aluminum alloy bars in Table 1, it can be seen that the present invention introduces three trace elements of Mn, Cr and Zr into the material with a specific ratio and a specific ratio between the three, and combines the two different extrusion speeds designed by the present invention, which can make the metal grains finer and more evenly distributed, and further improve the mechanical properties of the bar, such as tensile strength and elongation.

[0111] In comparative example 2, three trace elements, Mn, Cr and Zr, are introduced into the batching, but the total proportion of the three is 0.4%. In the extrusion process, the extrusion speed of the front section of the ingot is 1 mm / s, and the extrusion speed of the rear section is 0.5 mm / s, that is, the extrusion speed of the front section is less than the extrusion speed of the rear section, and the first solid solution heating rate is 1000 ° C / h. The performance and internal structure test results show that the total amount of the three trace elements Mn, Cr and Zr is controlled within a certain range, such as 0.1% ≤ Mn + Cr + Zr ≤ 0.2%, and combined with a specific two-stage extrusion speed, such as The extrusion speed in the front section is greater than the extrusion speed in the rear section. Only by adopting the above method can the metal grains be finer, the distribution is more uniform, and the mechanical properties are better. In particular, although the extrusion speed of Example 2 also adopts two-stage different extrusion speeds, the relative relationship between the two-stage extrusion speeds is not reasonably designed, and the purpose of improving the mechanical properties is not achieved. Similarly, although the total proportion of the three trace elements introduced in Example 3 is the same as that in the embodiment of the present invention, in the extrusion process, due to the unreasonable design of the relative relationship between the extrusion speeds in the front section and the rear section, the grain distribution and mechanical properties cannot be improved. The design of the front section being larger than the rear section of the present invention is based on the fact that the head of the front section is extruded first, and the tail of the rear section is extruded later. The temperature of the first section will be lower, and the temperature of the later section will become larger due to extrusion friction and heating, which will further affect the fine chemical distribution and uniformity of the metal grain size, and will also affect the mechanical properties of the rod. After designing the above-mentioned extrusion speed, the present invention can make the temperatures of the two sections basically the same or similar during the extrusion process, so that the heat of the entire rod is balanced during the extrusion process, and can also improve the metal grain size during the extrusion process. It is more fine and the distribution is more uniform, and its mechanical properties such as tensile strength and elongation can be further improved.

[0112] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those described herein, for example.

[0113] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An Al-Cu-Mg-Fe-Ni aluminum alloy bar, characterized in that: The aluminum alloy bar comprises the following components in weight percentage: Si≤0.02%, Fe 0.7%~0.9%, Cu 1.8%~2.1%, Mg 1.3%~1.4%, Ti 0.02%~0.08%, Ni0.7%~0.9%, 0.1%≤Mn+Cr+Zr≤0.2%; single impurity ≤0.05%, total impurities ≤0.1%, the remainder is Al, totaling 100%.

2. A method for preparing an Al-Cu-Mg-Fe-Ni aluminum alloy bar, characterized in that: The method for preparing the aluminum alloy bar comprises hot extruding an Al-Cu-Mg-Fe-Ni aluminum alloy ingot to obtain an extruded bar: Wherein, during the hot extrusion process, the heating temperature of the head of the aluminum alloy ingot is greater than the heating temperature of the tail; The front-end extrusion speed of the aluminum alloy ingot is greater than the rear-end extrusion speed; The Al-Cu-Mg-Fe-Ni aluminum alloy ingot is an ingot prepared by using the proportions of the components of the Al-Cu-Mg-Fe-Ni aluminum alloy bar described in claim 1, or an ingot prepared by using the proportions of the components of the aluminum alloy bar of grade 2A70 or grade 2D70.

3. The method for preparing the Al-Cu-Mg-Fe-Ni aluminum alloy rod according to claim 2, characterized in that: The Al-Cu-Mg-Fe-Ni aluminum alloy ingot is a heat-treated ingot, specifically comprising: According to the proportion of each component in the aluminum alloy bar, the ingredients are mixed and smelted to obtain an aluminum alloy ingot; The aluminum alloy ingot is subjected to homogenization heat treatment to obtain the heat-treated ingot.

4. The method for preparing the Al-Cu-Mg-Fe-Ni aluminum alloy bar according to claim 2 or 3, characterized in that: The method for preparing the Al-Cu-Mg-Fe-Ni aluminum alloy bar further comprises the following steps after the hot extrusion process: The extruded rod is subjected to solution heat treatment to obtain a solution heat treated rod; the solution heat treated rod is stretched and straightened to obtain a stretched and straightened rod; the stretched and straightened rod is subjected to aging heat treatment to obtain the Al-Cu-Mg-Fe-Ni aluminum alloy rod.

5. The method for preparing the Al-Cu-Mg-Fe-Ni aluminum alloy rod according to any one of claims 2 to 4, characterized in that: During the hot extrusion process, the heating temperature of the head of the aluminum alloy ingot is 5-20° C. higher than the heating temperature of the tail of the aluminum alloy ingot.

6. The method for preparing the Al-Cu-Mg-Fe-Ni aluminum alloy rod according to any one of claims 2 to 5, characterized in that: During the hot extrusion process, the heating temperature of the head of the aluminum alloy ingot is 430° C. to 440° C., and the heating temperature of the tail of the aluminum alloy ingot is 420° C. to 430° C.; And / or, the heating temperature of the hot extrusion die is 400°C to 420°C, and the heating temperature of the extrusion barrel in the die is 400°C to 420°C.

7. The method for preparing the Al-Cu-Mg-Fe-Ni aluminum alloy rod according to any one of claims 2 to 6, characterized in that: During the hot extrusion process, 1 / 2 of the length of the aluminum alloy ingot near the head is the front section, and 1 / 2 of the length of the aluminum alloy ingot near the tail is the rear section; And / or, the extrusion speed of the front section is 1.5-2.0 mm / s, and the extrusion speed of the rear section is 0.5-1.0 mm / s.

8. The method for preparing the Al-Cu-Mg-Fe-Ni aluminum alloy rod according to any one of claims 4 to 7, characterized in that: The solution heat treatment includes a first solution heat treatment and a second solution heat treatment; wherein, The first solution heat treatment process includes: a heating rate of 90°C / h to 160°C / h, a temperature of 440°C to 460°C, and a holding time of 0.5h to 1.0h; The second solution heat treatment process includes: a heating rate of 500°C / h to 1000°C / h, a temperature of 530°C to 540°C, and a holding time of 1.5h to 2.5h.

9. The method for preparing the Al-Cu-Mg-Fe-Ni aluminum alloy rod according to any one of claims 3 to 8, characterized in that: During the hot extrusion process, the die used is a flat die; the working band length of the die is 2 to 3 mm; And / or, during the stretching and straightening process, the stretching and straightening amount is ≤2.0%; And / or, the temperature of the aging heat treatment is 195° C. to 205° C., and the holding time of the aging heat treatment is 8 h to 12 h.

10. Use of the Al-Cu-Mg-Fe-Ni aluminum alloy rod according to claim 1 or the Al-Cu-Mg-Fe-Ni aluminum alloy rod obtained by the preparation method according to any one of claims 2 to 9 in aviation materials.

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