Aluminum alloy conductor with high conductivity and fatigue resistance, preparation method and application thereof

Abstract

The application belongs to the technical field of conductor materials, and particularly relates to an aluminum alloy conductor with high conductivity and fatigue resistance, a preparation method and application. The aluminum alloy conductor provided by the application is an Al-Mg-Si aluminum alloy conductor. The raw material composition of the Al-Mg-Si aluminum alloy conductor is improved by adding cerium (Ce), cerium (Ce) and controlling the addition amount of iron (Fe). Meanwhile, the conductivity of the Al-Mg-Si aluminum alloy conductor can be improved to 62.4% IACS and the fatigue strength can be improved to 236 MPa through a three-stage temperature increasing aging treatment and a plurality of liquid nitrogen deep cooling treatment processes. Therefore, the Al-Mg-Si aluminum alloy conductor provided by the application has high conductivity and fatigue resistance, and solves the technical problem of lacking an aluminum alloy conductor material with high conductivity and fatigue resistance in the prior art.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of conductor materials, and particularly relates to an aluminum alloy conductor with high conductivity and fatigue resistance, a preparation method and application thereof. BACKGROUND

[0002] In addition to using steel-cored aluminum stranded wires, Al-Mg-Si aluminum alloy is also used as a conductor material of electric wire and cable in a power grid transmission line. In the operation process of the power grid transmission line, the Al-Mg-Si aluminum alloy conductor material needs to have good fatigue resistance to meet the long-term safety and stability requirements of the power grid transmission line, and at the same time, the conductivity of the Al-Mg-Si aluminum alloy conductor material needs to be improved as much as possible to reduce the loss in the power transmission process.

[0003] In recent years, high-voltage, ultra-high-voltage and extra-high-voltage long-distance and large-capacity transmission lines have higher requirements for the fatigue resistance and conductivity of aluminum alloy conductor materials, and the fatigue resistance and conductivity of the aluminum alloy conductor material need to be improved. However, the conductivity and fatigue resistance of the currently provided aluminum alloy conductor material are not high, and it is difficult to meet the requirements of high-voltage, ultra-high-voltage and extra-high-voltage long-distance and large-capacity transmission networks. SUMMARY

[0004] Therefore, the application provides an aluminum alloy conductor with high conductivity and fatigue resistance, a preparation method and application thereof, to solve the technical problem of the lack of aluminum alloy conductor materials with high conductivity and fatigue resistance in the prior art.

[0005] The first aspect of the application provides an aluminum alloy conductor with high conductivity and fatigue resistance, and the raw material composition includes: Al: 98.00-99.62wt%, Mg: 0.05-0.50wt%, Si: 0.10-0.30wt%, Ce: 0.10-0.20wt%, Fe: 0.10-0.90wt%, B: 0.02-0.05wt%, Ti: 0.005-0.02wt% and Ni: 0.01-0.05wt%, wherein the mass ratio of Fe to Si in the raw material composition is (3.0-3.5): 1.

[0006] Preferably, the raw material composition includes: Al: 98.49-99.28wt%, Mg: 0.10-0.30wt%, Si: 0.10-0.20wt%, Ce: 0.15-0.20wt%, Fe: 0.32-0.70wt%, B: 0.03-0.05wt%, Ti: 0.01-0.02wt% and Ni: 0.01-0.04wt%, wherein the mass ratio of Fe to Si in the raw material composition is (3.2-3.5): 1.

[0007] The second aspect of the application provides a preparation method of an aluminum alloy conductor with high conductivity and fatigue resistance, which can prepare the aluminum alloy conductor with high conductivity and fatigue resistance of the first aspect; the preparation method comprises the following steps:

[0008] In step S1, industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy are sequentially subjected to melting, refining and casting forming to obtain an aluminum alloy ingot;

[0009] In step S2, the aluminum alloy ingot is sequentially subjected to homogenization treatment, hot extrusion, annealing, solid solution, aging treatment, deep cooling treatment and stress relief treatment to obtain the aluminum alloy conductor with high conductivity and fatigue resistance;

[0010] In step S2, the aging treatment is three-stage temperature-increasing aging treatment.

[0011] The deep cooling treatment is repeated at least twice.

[0012] Preferably, the three-stage temperature-increasing aging treatment comprises the following steps: sequentially performing first aging treatment at 125-140℃ for 0.5-2h, second aging treatment at 145-160℃ for 2-3.5h and third aging treatment at 175-190℃ for 0.5-2.5h.

[0013] Preferably, the deep cooling treatment is repeated at least 2-5 times by using liquid nitrogen for 12-36h.

[0014] Preferably, the stress relief treatment is performed at 130-150℃ for 1-3h.

[0015] Preferably, in step S1, the melting temperature is 750-800℃.

[0016] The refining agent used in the refining is NaCl, KCl and Na3AlF3.

[0017] Preferably, in step S2, the homogenization treatment is performed at 400-600℃ for 12-36h.

[0018] The extrusion temperature of the hot extrusion is 350-400℃, and the extrusion ratio is 20-27.

[0019] The annealing temperature is 200-300℃, and the annealing time is 5-10h.

[0020] The solid solution temperature is 500-550℃, and the solid solution holding time is 0.5-1h.

[0021] The third aspect of the present application provides an application of the aluminum alloy conductor with high conductivity and fatigue resistance in the electric wire and cable.

[0022] The fourth aspect of the present application provides an electric wire and cable comprising the aluminum alloy conductor with high conductivity and fatigue resistance and the insulating layer.

[0023] The insulating layer covers the aluminum alloy conductor with high conductivity and fatigue resistance.

[0024] In summary, the present application provides an aluminum alloy conductor with high conductivity and fatigue resistance, a preparation method and an application. The aluminum alloy conductor provided by the present application is an Al-Mg-Si aluminum alloy conductor, and the raw material composition comprises: Al: 98.00-99.62wt%, Mg: 0.05-0.50wt%, Si: 0.10-0.30wt%, Ce: 0.10-0.20wt%, Fe: 0.10-0.90wt%, B: 0.02-0.05wt%, Ti: 0.005-0.02wt%, and Ni: 0.01-0.05wt%. The addition amount of cerium (Ce), cerium (Ce) and iron (Fe) is introduced, and the aluminum alloy ingot is sequentially subjected to first, second and third aging treatment at 125-140℃, 145-160℃ and 175-190℃, and multiple liquid nitrogen deep cooling treatment, so that the conductivity of the Al-Mg-Si aluminum alloy conductor can be improved to 62.4% IACS, and the fatigue strength is improved to 236MPa, so that the Al-Mg-Si aluminum alloy conductor provided by the present application has high conductivity and fatigue resistance, thereby solving the technical problem of lack of aluminum alloy conductor material with high conductivity and fatigue resistance in the prior art. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the drawings needed in the specific embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0026] Figure 1 The flowchart of the preparation method of the aluminum alloy conductor with high conductivity and fatigue resistance provided by Example 1 of the present application is shown. DETAILED DESCRIPTION

[0027] The present application provides an aluminum alloy conductor with high conductivity and fatigue resistance, a preparation method and an application, which are used to solve the technical problem of lack of aluminum alloy conductor material with high conductivity and fatigue resistance in the prior art.

[0028] The technical solutions of the present application will be described clearly and completely in conjunction with the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0029] In view of the fact that the current aluminum alloy conductor cannot provide high-conductivity and fatigue-resistant aluminum alloy conductor materials, resulting in poor stability and large power loss during the operation of power grid transmission lines; the application provides an aluminum alloy conductor with high conductivity and fatigue resistance; the raw material composition of the aluminum alloy conductor provided by the application comprises Al: 98.00-99.62wt%, Mg: 0.05-0.50wt%, Si: 0.10-0.30wt%, Ce: 0.10-0.20wt%, Fe: 0.10-0.90wt%, B: 0.02-0.05wt%, Ti: 0.005-0.02wt% and Ni: 0.01-0.05wt%; the Al, Mg, Si, Ce, Fe, B, Ti and Ni in the aluminum alloy conductor are introduced by industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy; the aluminum alloy conductor provided by the application improves the raw material composition on the basis of the Al-Mg-Si aluminum alloy system; the improvement includes adding cerium (Ce) to the aluminum alloy conductor raw material, which fills the defects on the surface of the aluminum alloy, can improve the crystallization conditions of the Al-Mg-Si alloy, hinder the growth of the crystal grains, thereby refining the as-cast structure grain, can also refine the coarse eutectic silicon in the Al-Mg-Si alloy, thereby reducing the scattering of electrons to reduce the resistivity, and thus can improve the conductivity and fatigue strength of the Al-Mg-Si alloy; in addition, boron (B) is added to the aluminum alloy conductor raw material; in addition to refining the grains, the addition of boron (B) can also change the existence state of the impurities carried by the industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy in the Al-Mg-Si alloy and is beneficial to removing the impurities in the Al-Mg-Si alloy during the preparation process, thereby purifying the impurities in the Al-Mg-Si alloy and improving the conductivity and fatigue strength of the aluminum alloy conductor; in addition to adding cerium (Ce) and boron (B) elements to the Al-Mg-Si aluminum alloy system, the application also controls the addition amount of silicon (Si), magnesium (Mg) and iron (Fe) in the Al-Mg-Si aluminum alloy system; among them, the Mg in the aluminum alloy conductor raw material composition is controlled to be 0.05-0.50wt%, and the Si is controlled to be 0.10-0.30wt%, which improves the precipitation phase density of the Al-Mg-Si alloy during the preparation process and is beneficial to improving the fatigue strength and conductivity of the Al-Mg-Si alloy, and the mass ratio of Fe to Si in the raw material composition is controlled to be (3.0-3.5):1, and the content of iron does not exceed 3 times that of silicon.5 times, the amount of iron added is less, can make Al-Mg-Si alloy precipitate more easily, precipitate phase nucleation, fast, so that the fatigue strength and electrical conductivity of Al-Mg-Si alloy is improved, while adding more iron, easy to cause adverse effects on the fatigue strength and electrical conductivity of Al-Mg-Si alloy; At the same time, the Fe, Si, Ni, Ti added in the Al-Mg-Si aluminum alloy system is beneficial to the micro-alloying, which can appropriately reduce the ingot extrusion temperature, increase the ingot extrusion deformation, realize the purpose of breaking and refining Fe, Si, Ni, Ti alloy phase in Al-Mg-Si alloy, without reducing the fatigue performance of Al-Mg-Si alloy, thereby improving the electrical conductivity and fatigue strength of Al-Mg-Si alloy; The raw material composition of the Al-Mg-Si aluminum alloy is improved, so that the electrical conductivity of the Al-Mg-Si aluminum alloy can reach more than 61.5%IACS, and the fatigue strength of the obtained Al-Mg-Si alloy can reach 215MPa, and the electrical conductivity and fatigue resistance are higher than that of the Al-Mg-Si alloy without adding cerium (Ce), boron (B), controlling the amount of iron (Fe) and the mass ratio of Fe and Si.

[0030] In addition to improving the raw material composition of the Al-Mg-Si aluminum alloy, the preparation process of the Al-Mg-Si aluminum alloy is also improved; The improvement includes aging treatment process, cryogenic treatment process and stress relief treatment process; After the aluminum alloy ingot obtained by melting, refining, casting and forming is subjected to homogenization treatment, hot extrusion, annealing, solid solution treatment and other process treatments, three-stage temperature increasing aging treatment is carried out, wherein the three-stage temperature increasing aging treatment is first aging treatment at 125-140℃ for 0.5-2h, second aging treatment at 145-160℃ for 2-3.5h, and third aging treatment at 175-190℃ for 0.5-2.5h. The fatigue strength of the Al-Mg-Si aluminum alloy after three-stage temperature increasing aging treatment is significantly higher than that of the aluminum alloy without three-stage temperature increasing aging treatment, and the electrical conductivity of the Al-Mg-Si aluminum alloy can also be improved, thereby further improving the electrical conductivity and fatigue strength of the Al-Mg-Si aluminum alloy; After three-stage temperature increasing aging treatment, the application also uses liquid nitrogen (-196℃) cryogenic treatment for 12-36h, and repeats 2-5 times, and stress relief treatment at 130-150℃ for 1-3h. The fatigue strength of the Al-Mg-Si aluminum alloy after cryogenic treatment and stress relief treatment can be significantly improved, and the electrical conductivity can also be improved.

[0031] The Al-Mg-Si aluminum alloy conductor provided by the application will be specifically described below in combination with examples and experimental examples.

[0032] Embodiment 1

[0033] The embodiment 1 of the present application provides a preparation method of an aluminum alloy conductor with high conductivity and fatigue resistance, which comprises the steps of raw material preparation, melting and casting of aluminum alloy and process treatment.

[0034] In the step of raw material preparation, 100 kg of raw materials including industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy are weighed according to the proportions of Al: 98.98wt%, Mg: 0.20wt%, Si: 0.15wt%, Ce: 0.15wt%, Fe: 0.45wt%, B: 0.04wt%, Ti: 0.01wt% and Ni: 0.02wt%.

[0035] The step of melting and casting of aluminum alloy comprises the following steps: first, heating the industrial pure aluminum (mass fraction ≥ 99.7%) to 750℃, and then melting to obtain aluminum liquid; increasing the temperature of the aluminum liquid to 760℃, and then sequentially adding industrial pure magnesium (mass fraction ≥ 99.7%), industrial pure silicon (mass fraction ≥ 99.7%), Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy; melting; then adding refining agents (NaCl, KCl and Na3AlF3 in a mass ratio of 40:25:20) in an amount of 1.5 kg / t for refining; maintaining for 10 min; then skimming and casting to obtain aluminum alloy ingot.

[0036] The step of process treatment comprises the following steps:

[0037] The aluminum alloy ingot is subjected to homogenization treatment at 400℃ for 36 h, and then the mold, extrusion cylinder and extrusion pad required for extrusion are heated to 380℃, and the aluminum alloy ingot after homogenization treatment is subjected to hot extrusion with an extrusion ratio of 25; the aluminum alloy ingot after hot extrusion is annealed at 200℃ for 10 h; and solid solution treatment is performed at 550℃ for 0.5 h in a high-precision box-type resistance furnace.

[0038] After furnace cooling, three-stage temperature increasing aging treatment is performed, and the three-stage temperature increasing aging treatment process comprises the following steps: first aging treatment at 130℃ for 1.5 h, then second aging treatment at 150℃ for 3 h, and third aging treatment at 180℃ for 2 h, and air cooling to room temperature.

[0039] The cooled aluminum alloy ingot is subjected to deep cooling treatment three times using liquid nitrogen (-196℃) for 24 h, and after each deep cooling treatment, the aluminum alloy ingot is naturally warmed at room temperature and then subjected to deep cooling treatment using liquid nitrogen (-196℃) again.

[0040] After the third deep cryogenic treatment using liquid nitrogen (-196℃), the equal aluminum alloy ingot is naturally cooled at room temperature, and then stress relief treatment is carried out at 150℃ for 2h to obtain the aluminum alloy conductor with high conductivity and fatigue resistance.

[0041] Embodiment 2

[0042] The embodiment 2 of the present application provides a preparation method of an aluminum alloy conductor with high conductivity and fatigue resistance, which comprises raw material preparation, melting and casting of aluminum alloy and process treatment.

[0043] In the step of raw material preparation, 100Kg of corresponding raw materials including industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy are weighed according to the proportion of Al: 99.015wt%, Mg: 0.30wt%, Si: 0.10wt%, Ce: 0.20wt%, Fe: 0.32wt%, B: 0.03wt%, Ti: 0.005wt% and Ni: 0.03wt%.

[0044] The step of melting and casting of aluminum alloy comprises the following steps: first, heating the industrial pure aluminum (mass fraction ≥ 99.7%) to 750℃, and then melting to obtain aluminum liquid; increasing the temperature of the aluminum liquid to 760℃, and then sequentially adding industrial pure magnesium (mass fraction ≥ 99.7%), industrial pure silicon (mass fraction ≥ 99.7%), Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy; melting; then adding refining agents (NaCl, KCl and Na3AlF3 in a mass ratio of 40:25:20) in an amount of 1.5kg / t for refining; maintaining for 10min; then skimming and casting to obtain an aluminum alloy ingot.

[0045] The step of process treatment comprises the following steps:

[0046] The aluminum alloy ingot is subjected to homogenization treatment at 450℃ for 24h, and then the mold, extrusion cylinder and extrusion pad required for extrusion are heated to 380℃, and the aluminum alloy ingot after homogenization treatment is subjected to hot extrusion with an extrusion ratio of 25; the aluminum alloy ingot after hot extrusion is annealed at 250℃ for 6h; and solid solution treatment is carried out at 500℃ for 1h in a high-precision box-type resistance furnace.

[0047] After furnace cooling, three-stage temperature increasing aging treatment is carried out, and the process of three-stage temperature increasing aging treatment is as follows: first aging treatment at 140℃ for 1h, then second aging treatment at 155℃ for 2.5h, and then third aging treatment at 185℃ for 1h, and air cooling to room temperature.

[0048] The cooled aluminum alloy ingot is frozen using liquid nitrogen (-196℃) for 24h for 4 times of cryogenic treatment, and after each cryogenic treatment, the aluminum alloy ingot is naturally cooled at room temperature and then cryogenically treated using liquid nitrogen (-196℃) again;

[0049] After the fourth cryogenic treatment using liquid nitrogen (-196℃), the aluminum alloy ingot is naturally cooled at room temperature, and then stress relief treatment is performed at 130℃ for 2h to obtain an aluminum alloy conductor with high conductivity and fatigue resistance.

[0050] Embodiment 3

[0051] The embodiment 3 of the present application provides a preparation method of an aluminum alloy conductor with high conductivity and fatigue resistance, which comprises raw material preparation, melting and casting of aluminum alloy, and process treatment.

[0052] The raw material preparation step comprises weighing 100Kg of corresponding raw materials such as industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy, and Ni-Al intermediate alloy according to the proportions of Al: 99.315wt%, Mg: 0.10wt%, Si: 0.10wt%, Ce: 0.10wt%, Fe: 0.35wt%, B: 0.02wt%, Ti: 0.005wt%, and Ni: 0.01wt%.

[0053] The melting and casting of aluminum alloy step comprises: first heating the industrial pure aluminum (mass fraction ≥99.7%) to 750℃, melting the aluminum liquid, increasing the temperature of the aluminum liquid to 780℃, then sequentially adding industrial pure magnesium (mass fraction ≥99.7%), industrial pure silicon (mass fraction ≥99.7%), Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy, and Ni-Al intermediate alloy, melting, then adding refining agents (NaCl, KCl, and Na3AlF3 in a mass ratio of 45:30:15) in an amount of 1.5kg / t for refining, maintaining for 10min, then skimming and casting to obtain an aluminum alloy ingot.

[0054] The process treatment step comprises:

[0055] The aluminum alloy ingot is homogenized at 500℃ for 12h, then the mold, extrusion cylinder, and extrusion pad required for extrusion are heated to 400℃, the homogenized aluminum alloy ingot is hot extruded with an extrusion ratio of 25, the hot extruded aluminum alloy ingot is annealed at 300℃ for 5h, and then solid solution treated at 550℃ for 0.5h in a high-precision box-type resistance furnace.

[0056] After furnace cooling, three-stage temperature increasing aging treatment is carried out, and the three-stage temperature increasing aging treatment process is as follows: first aging treatment is carried out at 140 DEG C for 1 h, then second aging treatment is carried out at 155 DEG C for 2.5 h, and then third aging treatment is carried out at 185 DEG C for 1 h, and air cooling is carried out to room temperature;

[0057] The cooled aluminum alloy ingot is frozen for 24 h using liquid nitrogen (-196 DEG C) to carry out deep cooling treatment 4 times, and after each deep cooling treatment, the aluminum alloy ingot is naturally cooled at room temperature and then deep cooling treatment is carried out using liquid nitrogen (-196 DEG C) again.

[0058] After the fourth deep cooling treatment using liquid nitrogen (-196 DEG C), the aluminum alloy ingot is naturally cooled at room temperature, and then stress relief treatment is carried out at 130 DEG C for 2 h to obtain an aluminum alloy conductor with high conductivity and fatigue resistance.

[0059] Embodiment 4

[0060] The embodiment 4 of the present application provides a preparation method of an aluminum alloy conductor with high conductivity and fatigue resistance, and the preparation method comprises raw material preparation, aluminum alloy melting and casting, and process treatment.

[0061] In the raw material preparation step, 100 kg of corresponding raw materials such as industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy are weighed according to the proportions of Al: 98.98wt%, Mg: 0.20wt%, Si: 0.15wt%, Ce: 0.15wt%, Fe: 0.45wt%, B: 0.04wt%, Ti: 0.01wt% and Ni: 0.02wt%.

[0062] The aluminum alloy melting and casting step comprises the following steps: first, the industrial pure aluminum (mass fraction ≥ 99.7%) is heated to 750 DEG C, and after melting, the temperature of the aluminum liquid is increased to 760 DEG C, then the industrial pure magnesium (mass fraction ≥ 99.7%), the industrial pure silicon (mass fraction ≥ 99.7%), the Ce-Al intermediate alloy, the Fe-Al intermediate alloy, the B-Al intermediate alloy, the Ti-Al intermediate alloy and the Ni-Al intermediate alloy are sequentially added, and then the refining agent (the mass ratio of NaCl, KCl and Na3AlF3 is 40:25:20) is added in an amount of 1.5 kg / t for refining, and the temperature is maintained for 10 min, then slagging and casting are carried out to obtain the aluminum alloy ingot.

[0063] The process treatment step includes: homogenizing the aluminum alloy ingot at 400 DEG C for 36h, then heating the extrusion die, extrusion cylinder and extrusion pad to 380 DEG C, hot extruding the homogenized aluminum alloy ingot, and the extrusion ratio is 25; annealing the hot extruded aluminum alloy ingot at 200 DEG C for 10h; and solid solution treatment at 550 DEG C for 0.5h in a high-precision box resistance furnace.

[0064] After furnace cooling, three-stage temperature increasing aging treatment is carried out, and the three-stage temperature increasing aging treatment process is: first aging treatment at 130 DEG C for 1.5h, then second aging at 150 DEG C for 3h, and then third aging treatment at 180 DEG C for 2h, and air cooling to room temperature.

[0065] The cooled aluminum alloy ingot is frozen for 24h using liquid nitrogen (-196 DEG C) for deep cooling treatment 4 times, and after each deep cooling treatment, the aluminum alloy ingot is naturally cooled at room temperature and then deep cooled using liquid nitrogen (-196 DEG C) again.

[0066] After the fourth deep cooling treatment using liquid nitrogen (-196 DEG C), the aluminum alloy ingot is naturally cooled at room temperature, and then stress relief treatment is carried out at 150 DEG C for 2h, to obtain an aluminum alloy conductor with high conductivity and fatigue resistance.

[0067] Example 5

[0068] The embodiment 5 of the present application provides a preparation method of an aluminum alloy conductor with high conductivity and fatigue resistance, and the preparation method includes raw material preparation, melting and casting of aluminum alloy and process treatment.

[0069] The raw material preparation step includes: weighing 100Kg of corresponding raw materials such as industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy according to the proportions of Al: 98.98wt%, Mg: 0.20wt%, Si: 0.15wt%, Ce: 0.15wt%, Fe: 0.45wt%, B: 0.04wt%, Ti: 0.01wt% and Ni: 0.02wt%.

[0070] The step of melting and casting the aluminum alloy comprises the following steps: firstly, heating the industrial pure aluminum (mass fraction ≥ 99.7%) to 750℃, and obtaining the aluminum liquid after the industrial pure aluminum is melted; then, increasing the temperature of the aluminum liquid to 760℃, and then adding the industrial pure magnesium (mass fraction ≥ 99.7%), the industrial pure silicon (mass fraction ≥ 99.7%), the Ce-Al intermediate alloy, the Fe-Al intermediate alloy, the B-Al intermediate alloy, the Ti-Al intermediate alloy and the Ni-Al intermediate alloy in sequence; melting; then, adding the refining agent (the mass ratio of NaCl, KCl and Na3AlF3 is 40:25:20) in an amount of 1.5kg / t for refining, and keeping the temperature for 10min; and then, removing the slag and casting to obtain the aluminum alloy ingot.

[0071] The step of process treatment comprises the following steps: keeping the aluminum alloy ingot at 400℃ for 36h for homogenization treatment; then, heating the extrusion mold, the extrusion cylinder and the extrusion pad to 380℃; then, performing hot extrusion on the aluminum alloy ingot after the homogenization treatment, and the extrusion ratio is 25; then, annealing the aluminum alloy ingot after the hot extrusion at 200℃ for 10h; then, performing solid solution treatment on the aluminum alloy ingot in a high-precision box-type resistance furnace at 550℃ for 0.5h; then, performing three-stage temperature increasing aging treatment on the aluminum alloy ingot after the solid solution treatment,

[0072] The three-stage temperature increasing aging treatment process comprises the following steps: first, performing first aging treatment at 130℃ for 1.5h; then, performing second aging treatment at 150℃ for 3h; and then, performing third aging treatment at 180℃ for 2h, and then, air cooling to room temperature;

[0073] After the cooling, the aluminum alloy ingot is frozen for 24h using liquid nitrogen (-196℃) for deep cooling treatment for 5 times, and after each deep cooling treatment, the aluminum alloy ingot is naturally warmed at room temperature and then deep cooling treatment is performed again using liquid nitrogen (-196℃);

[0074] After the fifth deep cooling treatment using liquid nitrogen (-196℃), the aluminum alloy ingot is naturally warmed at room temperature, and then, stress relief treatment is performed at 150℃ for 2h, so that the aluminum alloy conductor with high conductivity and fatigue resistance is obtained.

[0075] Embodiment 6

[0076] The embodiment 6 of the present application provides a preparation method of an Al-Mg-Si aluminum alloy conductor, which is a first comparative embodiment of the embodiment 1, and the preparation method comprises the following steps: raw material preparation, melting and casting the aluminum alloy and process treatment.

[0077] The raw material preparation step includes: weighing 100 kg of corresponding industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy, and Ni-Al intermediate alloy, etc. according to the proportions of Al: 99.13 wt%, Mg: 0.20 wt%, Si: 0.15 wt%, Fe: 0.45 wt%, B: 0.04 wt%, Ti: 0.01 wt%, and Ni: 0.02 wt%.

[0078] The melting and casting of the aluminum alloy step includes: first heating the industrial pure aluminum (mass fraction ≥ 99.7%) to 750℃, melting the aluminum liquid, and then increasing the temperature of the aluminum liquid to 760℃, and then sequentially adding industrial pure magnesium (mass fraction ≥ 99.7%), industrial pure silicon (mass fraction ≥ 99.7%), Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy, and Ni-Al intermediate alloy, melting, then adding refining agents (the mass ratio of NaCl, KCl, and Na3AlF3 is 40:25:20) in an amount of 1.5 kg / t, refining, holding for 10 min, then skimming and casting to obtain an aluminum alloy ingot.

[0079] The process treatment step includes: homogenizing the aluminum alloy ingot at 400℃ for 36h, then heating the extrusion mold, extrusion cylinder, and extrusion pad, etc. to 380℃, hot extruding the homogenized aluminum alloy ingot, with an extrusion ratio of 25, annealing the hot extruded aluminum alloy ingot at 200℃ for 10h, and then solid solution treatment at 550℃ for 0.5h in a high-precision box-type resistance furnace.

[0080] After furnace cooling, three-stage temperature increasing aging treatment is performed, which includes first aging treatment at 130℃ for 1.5h, then second aging treatment at 150℃ for 3h, and third aging treatment at 180℃ for 2h, and air cooling to room temperature.

[0081] The cooled aluminum alloy ingot is frozen for 24h using liquid nitrogen (-196℃) for deep cooling treatment three times, and after each deep cooling treatment, the aluminum alloy ingot is naturally warmed at room temperature before being deep cooled using liquid nitrogen (-196℃) again.

[0082] After the third deep cooling treatment using liquid nitrogen (-196℃), the aluminum alloy ingot is naturally warmed at room temperature before being stress relieved at 150℃ for 2h, and an Al-Mg-Si aluminum alloy conductor is obtained.

[0083] Example 7

[0084] The embodiment 7 of the application provides a preparation method of an Al-Mg-Si aluminum alloy conductor, which is a second comparative example of the embodiment 1, and the preparation method comprises the steps of raw material preparation, melting and casting of the aluminum alloy and process treatment.

[0085] In the step of raw material preparation, 100 kg of raw materials including industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy are weighed according to the proportion of Al: 99.02 wt%, Mg: 0.20 wt%, Si: 0.15 wt%, Ce: 0.15 wt%, Fe: 0.45 wt%, Ti: 0.01 wt% and Ni: 0.02 wt%.

[0086] The step of melting and casting of the aluminum alloy comprises the following steps: first, the industrial pure aluminum (mass fraction ≥ 99.7%) is heated to 750 ℃, and the aluminum liquid is obtained after melting; the temperature of the aluminum liquid is increased to 760 ℃, and then the industrial pure magnesium (mass fraction ≥ 99.7%), the industrial pure silicon (mass fraction ≥ 99.7%), the Ce-Al intermediate alloy, the Fe-Al intermediate alloy, the Ti-Al intermediate alloy and the Ni-Al intermediate alloy are sequentially added and melted; then, the refining agent (the mass ratio of NaCl, KCl and Na3AlF3 is 40:25:20) is added in an amount of 1.5 kg / t for refining, and the temperature is kept for 10 min; then, the slag is removed and casting is performed to obtain the aluminum alloy ingot.

[0087] The step of process treatment comprises the following steps: the aluminum alloy ingot is kept at 400 ℃ for 36 h for homogenization treatment; then, the mold, the extrusion cylinder and the extrusion pad required for extrusion are heated to 380 ℃, and the aluminum alloy ingot after homogenization treatment is hot extruded with an extrusion ratio of 25; the aluminum alloy ingot after hot extrusion is annealed at 200 ℃ for 10 h; the high-precision box-type resistance furnace is used for solid solution treatment at 550 ℃ for 0.5 h.

[0088] After furnace cooling, three-stage temperature increasing aging treatment is performed, and the three-stage temperature increasing aging treatment process comprises the following steps: first aging treatment is performed at 130 ℃ for 1.5 h, then second aging treatment is performed at 150 ℃ for 3 h, and then third aging treatment is performed at 180 ℃ for 2 h, and air cooling is performed to room temperature.

[0089] The aluminum alloy ingot after cooling is frozen for 24 h using liquid nitrogen (-196 ℃) for deep cooling treatment three times, and after each deep cooling treatment, the liquid nitrogen (-196 ℃) is used for deep cooling treatment after natural temperature rise at room temperature.

[0090] After the third deep cooling treatment using liquid nitrogen (-196℃), the equal-aluminum alloy ingot is naturally cooled at room temperature, and then is stress relieved at 150℃ for 2h to obtain the Al-Mg-Si aluminum alloy conductor.

[0091] Embodiment 8

[0092] Embodiment 8 of the present application provides a preparation method of an Al-Mg-Si aluminum alloy conductor, which is a third comparative embodiment of embodiment 1, and the preparation method comprises raw material preparation, melting and casting of aluminum alloy and process treatment.

[0093] In the raw material preparation step, 100kg of raw materials including industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy are weighed according to the proportions of Al: 98.83wt%, Mg: 0.20wt%, Si: 0.15wt%, Ce: 0.15wt%, Fe: 0.60wt%, B: 0.04wt%, Ti: 0.01wt% and Ni: 0.02wt%.

[0094] The melting and casting of aluminum alloy step comprises the following steps: first, heating the industrial pure aluminum (mass fraction ≥ 99.7%) to 750℃, melting the aluminum liquid, and then increasing the temperature of the aluminum liquid to 760℃; then, adding the industrial pure magnesium (mass fraction ≥ 99.7%), industrial pure silicon (mass fraction ≥ 99.7%), Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy in sequence; melting; then adding refining agents (NaCl, KCl and Na3AlF3 in a mass ratio of 40:25:20) in an amount of 1.5kg / t for refining; maintaining for 10min; then skimming and casting to obtain the aluminum alloy ingot.

[0095] The process treatment step comprises the following steps: homogenizing the aluminum alloy ingot at 400℃ for 36h; heating the extrusion mold, extrusion cylinder and extrusion pad to 380℃; hot extruding the homogenized aluminum alloy ingot, with an extrusion ratio of 25; annealing the hot extruded aluminum alloy ingot at 200℃ for 10h; solid solution treatment at 550℃ for 0.5h in a high-precision box-type resistance furnace;

[0096] After furnace cooling, three-stage temperature increasing aging treatment is performed, and the three-stage temperature increasing aging treatment process comprises the following steps: first aging treatment at 130℃ for 1.5h, then second aging treatment at 150℃ for 3h, and then third aging treatment at 180℃ for 2h, and air cooling to room temperature.

[0097] The cooled aluminum alloy ingot is frozen using liquid nitrogen (-196℃) for 24h to perform three times of cryogenic treatment, and after each cryogenic treatment, the aluminum alloy ingot is naturally cooled at room temperature and then frozen using liquid nitrogen (-196℃) for cryogenic treatment again;

[0098] After the third cryogenic treatment using liquid nitrogen (-196℃), the aluminum alloy ingot is naturally cooled at room temperature, and then stress relief treatment is performed at 150℃ for 2h to obtain the Al-Mg-Si aluminum alloy conductor.

[0099] Embodiment 9

[0100] The embodiment 9 of the present application provides a preparation method of an Al-Mg-Si aluminum alloy conductor, which is a fourth comparative embodiment of the embodiment 1, and the preparation method comprises raw material preparation, melting and casting of the aluminum alloy, and process treatment.

[0101] In the raw material preparation step, 100Kg of corresponding raw materials including industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy are weighed according to the proportions of Al: 98.98wt%, Mg: 0.20wt%, Si: 0.15wt%, Ce: 0.15wt%, Fe: 0.45wt%, B: 0.04wt%, Ti: 0.01wt% and Ni: 0.02wt%.

[0102] The melting and casting of the aluminum alloy step comprises: first, heating the industrial pure aluminum (mass fraction ≥ 99.7%) to 750℃, melting the aluminum liquid, and then increasing the temperature of the aluminum liquid to 760℃, and then sequentially adding the industrial pure magnesium (mass fraction ≥ 99.7%), the industrial pure silicon (mass fraction ≥ 99.7%), the Ce-Al intermediate alloy, the Fe-Al intermediate alloy, the B-Al intermediate alloy, the Ti-Al intermediate alloy and the Ni-Al intermediate alloy, melting, and then adding the refining agent (NaCl, KCl and Na3AlF3 in a mass ratio of 40:25:20) in an amount of 1.5kg / t for refining, and then holding for 10min, and then slagging and casting to obtain the aluminum alloy ingot.

[0103] The process treatment step comprises: homogenizing the aluminum alloy ingot at 400℃ for 36h, then heating the extrusion required mold, extrusion cylinder and extrusion pad to 380℃, and then hot extruding the homogenized aluminum alloy ingot with an extrusion ratio of 25; annealing the hot extruded aluminum alloy ingot at 200℃ for 10h; and performing solid solution treatment at 550℃ for 0.5h using a high-precision box-type resistance furnace.

[0104] After furnace cooling, aging treatment is performed, and the aging treatment process is first aging treatment at 130℃ for 1.5h, and then second aging treatment at 150℃ for 3h, and air cooling to room temperature;

[0105] The cooled aluminum alloy ingot is frozen for 24h using liquid nitrogen (-196℃) for three times of deep cooling treatment, and after each deep cooling treatment, the aluminum alloy ingot is naturally cooled at room temperature and then deep cooled using liquid nitrogen (-196℃) again.

[0106] After the third deep cooling treatment using liquid nitrogen (-196℃), the aluminum alloy ingot is naturally cooled at room temperature, and then stress relief treatment is performed at 150℃ for 2h, to obtain the Al-Mg-Si aluminum alloy conductor.

[0107] Embodiment 10

[0108] Embodiment 10 of the present application provides a preparation method of an Al-Mg-Si aluminum alloy conductor, which is a fifth comparative embodiment of embodiment 1, and the preparation method comprises raw material preparation, aluminum alloy melting and casting, and process treatment.

[0109] In the raw material preparation step, 100Kg of corresponding raw materials including industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy are weighed according to the proportions of Al: 98.98wt%, Mg: 0.20wt%, Si: 0.15wt%, Ce: 0.15wt%, Fe: 0.45wt%, B: 0.04wt%, Ti: 0.01wt% and Ni: 0.02wt%.

[0110] The aluminum alloy melting and casting step comprises: first, heating the industrial pure aluminum (mass fraction ≥ 99.7%) to 750℃, melting the aluminum liquid, and then increasing the temperature of the aluminum liquid to 760℃, and then sequentially adding industrial pure magnesium (mass fraction ≥ 99.7%), industrial pure silicon (mass fraction ≥ 99.7%), Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy, melting, and then adding refining agents (NaCl, KCl and Na3AlF3 in a mass ratio of 40:25:20) in an amount of 1.5kg / t for refining, and then holding for 10min, and then skimming and casting to obtain the aluminum alloy ingot.

[0111] The process treatment step includes: homogenizing the aluminum alloy ingot at 400℃ for 36h, then heating the extrusion die, extrusion cylinder and extrusion pad to 380℃, hot extruding the homogenized aluminum alloy ingot, and the extrusion ratio is 25; annealing the hot extruded aluminum alloy ingot at 200℃ for 10h; solid solution treatment at 550℃ for 0.5h in a high-precision box resistance furnace; after furnace cooling,

[0112] carrying out three-stage temperature increasing aging treatment, the three-stage temperature increasing aging treatment process is: first aging treatment at 130℃ for 1.5h, then second aging treatment at 150℃ for 3h, and then third aging treatment at 180℃ for 2h, and air cooling to room temperature.

[0113] directly performing stress relief treatment on the cooled aluminum alloy ingot at 150℃ for 2h to obtain the Al-Mg-Si aluminum alloy conductor.

[0114] Embodiment 11

[0115] The embodiment 11 of the present application provides a preparation method of an Al-Mg-Si aluminum alloy conductor, which is a sixth comparative embodiment of the embodiment 1, and the preparation method comprises raw material preparation, melting and casting of aluminum alloy and process treatment.

[0116] The raw material preparation step includes: weighing 100Kg of corresponding raw materials such as industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy according to the proportions of Al: 98.98wt%, Mg: 0.20wt%, Si: 0.15wt%, Ce: 0.15wt%, Fe: 0.45wt%, B: 0.04wt%, Ti: 0.01wt% and Ni: 0.02wt%.

[0117] The melting and casting of aluminum alloy step includes: first heating the industrial pure aluminum (mass fraction ≥ 99.7%) to 750℃, melting the aluminum liquid after heating, increasing the temperature of the aluminum liquid to 760℃, then adding industrial pure magnesium (mass fraction ≥ 99.7%), industrial pure silicon (mass fraction ≥ 99.7%), Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy in sequence, melting, then adding refining agents (the mass ratio of NaCl, KCl and Na3AlF3 is 40:25:20) in an amount of 1.5kg / t for refining, maintaining for 10min, then skimming and casting to obtain the aluminum alloy ingot.

[0118] The process treatment steps include: homogenizing the aluminum alloy ingot at 400℃ for 36h, then heating the extrusion die, extrusion cylinder and extrusion pad to 380℃, hot extruding the homogenized aluminum alloy ingot, the extrusion ratio is 25; annealing the hot extruded aluminum alloy ingot at 200℃ for 10h; solid solution treatment at 550℃ for 0.5h in a high-precision box-type resistance furnace;

[0119] After furnace cooling, three-stage temperature increasing aging treatment is carried out, the three-stage temperature increasing aging treatment process is: first aging treatment at 130℃ for 1.5h, then second aging treatment at 150℃ for 3h, and then third aging treatment at 180℃ for 2h, and air cooling to room temperature;

[0120] The cooled aluminum alloy ingot is subjected to deep cooling treatment three times using liquid nitrogen (-196℃), the holding time of each deep cooling treatment is 24h, and after each deep cooling treatment, the aluminum alloy ingot is naturally cooled to room temperature and then subjected to deep cooling treatment using liquid nitrogen (-196℃) again.

[0121] After the third deep cooling treatment using liquid nitrogen (-196℃), the aluminum alloy ingot is naturally cooled to room temperature, and an Al-Mg-Si aluminum alloy conductor is obtained.

[0122] Experimental Example 1

[0123] The performance of the aluminum alloy conductors provided in Examples 1-5 and Examples 6-11 is tested in Experimental Example 1 of the present application. In the performance test, the electrical conductivity is measured by a direct current double-arm bridge, and the maximum stress when the aluminum alloy conductor does not break after being subjected to alternating load for 10 7 times is tested by a bending fatigue testing machine, and the test results are shown in Table 1.

[0124] Fatigue strength / MPa Electrical conductivity / % IACS Example 1 220 62.4 Example 2 236 63.1 Example 3 215 61.5 Example 4 221 63.9 Example 5 232 64.2 Example 6 192 45.4 Example 7 185 48.6 Example 8 176 44.3 Example 9 121 60.1 Example 10 206 40.7 Example 11 105 61.2

[0125] Table 1

[0126] As can be seen from the performance test results of Comparative Examples 6 and 7 and Example 1, after adding cerium (Ce) and boron (B) to the Al-Mg-Si aluminum alloy, the electrical conductivity and fatigue resistance of the Al-Mg-Si aluminum alloy are both improved, which indicates that the addition of Ce and B can refine the grain, remove impurities, and improve the electrical conductivity and fatigue resistance of the aluminum alloy.

[0127] As can be seen from the performance test results of Comparative Example 8 and Example 1, when too much iron (Fe) is added, the amount of iron (Fe) is 4 times the amount of silicon (Si), which reduces the electrical conductivity and fatigue resistance of the Al-Mg-Si aluminum alloy, which may be due to the effect of too much iron (Fe) on the grain precipitation behavior of the Al-Mg-Si aluminum alloy, the grain precipitation rate slows down, the amount decreases, and it becomes difficult to precipitate; by controlling the amount of iron (Fe) to be (3.0-3.5) times the amount of silicon (Si), the electrical conductivity of the Al-Mg-Si aluminum alloy can be improved from 44.3% IACS to 62.4% IACS, which is more than 40% improvement in electrical conductivity, the fatigue strength is improved from 176 MPa to 220 MPa, which is more than 25% improvement in fatigue strength, and the electrical conductivity and fatigue resistance of the Al-Mg-Si aluminum alloy are significantly improved.

[0128] As can be seen from the performance test results of Comparative Example 9 and Example 1, when only secondary aging treatment is performed, the electrical conductivity of the Al-Mg-Si aluminum alloy is 60.1% IACS, and the fatigue strength is only 121 MPa, and when tertiary temperature increasing aging treatment is performed, the electrical conductivity of the Al-Mg-Si aluminum alloy is improved to 62.4% IACS, and the fatigue strength is only 220 MPa, which is about 4% improvement in electrical conductivity, and more than 80% improvement in fatigue strength, which shows that the third aging treatment at a temperature of 75-190°C can significantly improve the grain microstructure of the Al-Mg-Si aluminum alloy, significantly improving the fatigue strength, and also improving the electrical conductivity to a certain extent.

[0129] As can be seen from the performance test results of Comparative Examples 10 and 11 and Example 1, cryogenic treatment using liquid nitrogen has a greater effect on the electrical conductivity of the Al-Mg-Si aluminum alloy, and stress relief at 150°C has a greater effect on the fatigue strength of the Al-Mg-Si aluminum alloy; therefore, the Al-Mg-Si aluminum alloy can be subjected to liquid nitrogen cryogenic treatment or stress relief at 150°C as needed; for example, to improve the electrical conductivity of the Al-Mg-Si aluminum alloy, the Al-Mg-Si aluminum alloy can be subjected to one more liquid nitrogen cryogenic treatment or two liquid nitrogen cryogenic treatments on the basis of three liquid nitrogen cryogenic treatments, as shown in Examples 4-5, which can improve the electrical conductivity of the Al-Mg-Si aluminum alloy from 62.4% IACS to 63.9% IACS and 64.2% IACS.

[0130] The above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An aluminum alloy conductor having both high electrical conductivity and fatigue resistance, characterized by, The raw material composition comprises: Al: 98.00-99.62wt%, Mg: 0.05-0.50wt%, Si: 0.10-0.30wt%, Ce: 0.10-0.20wt%, Fe: 0.10-0.90wt%, B: 0.02-0.05wt%, Ti: 0.005-0.02wt%, and Ni: 0.01-0.05wt%; wherein the mass ratio of Fe to Si in the raw material composition is (3.0-3.5):1; The preparation method of the aluminum alloy conductor with high conductivity and fatigue resistance comprises the following steps: In step S1, industrial pure aluminum, industrial pure magnesium, industrial pure silicon, Ce-Al intermediate alloy, Fe-Al intermediate alloy, B-Al intermediate alloy, Ti-Al intermediate alloy and Ni-Al intermediate alloy are sequentially subjected to melting, refining and casting forming to obtain an aluminum alloy ingot; In step S2, the aluminum alloy ingot is sequentially subjected to homogenization treatment, hot extrusion, annealing, solid solution, aging treatment, deep cooling treatment and stress relief treatment to obtain the aluminum alloy conductor with high conductivity and fatigue resistance; In step S2, the aging treatment comprises the following steps: sequentially performing first aging treatment at 125-140 DEG C for 0.5-2h, second aging treatment at 145-160 DEG C for 2-3.5h and third aging treatment at 175-190 DEG C for 0.5-2.5h; The deep cooling treatment is performed for 12-36h at least 2-5 times using liquid nitrogen.

2. The aluminum alloy conductor with high conductivity and fatigue resistance according to claim 1, characterized in that, The raw material composition comprises: Al: 98.00-99.62wt%, Mg: 0.05-0.50wt%, Si: 0.10-0.30wt%, Ce: 0.10-0.20wt%, Fe: 0.10-0.90wt%, B: 0.02-0.05wt%, Ti: 0.005-0.02wt%, and Ni: 0.01-0.05wt%; wherein the mass ratio of Fe to Si in the raw material composition is (3.0-3.5):1; 3. The aluminum alloy conductor with high conductivity and fatigue resistance according to claim 1, wherein In step S2, the stress relief treatment is performed at 130-150 DEG C for 1-3h.

4. The aluminum alloy conductor with high conductivity and fatigue resistance according to claim 1, wherein In step S1, the melting temperature is 750-800 DEG C; The refining agent used in the refining is NaCl, KCl and Na3AlF3.

5. The aluminum alloy conductor with high conductivity and fatigue resistance according to claim 1, wherein In step S2, the homogenization treatment temperature is 400-600 DEG C, and the homogenization treatment holding time is 12-36h; The extrusion temperature of the hot extrusion is 350-400 DEG C, and the extrusion ratio is 20-27; The annealing temperature is 200-300 DEG C, and the annealing time is 5-10h; The solid solution temperature is 500-550 DEG C, and the solid solution holding time is 0.5-1h.

6. The aluminum alloy conductor with high conductivity and fatigue resistance according to any one of claims 1-5 is applied to an electric wire and cable.

7. An electric wire cable, characterized by, The aluminum alloy conductor with high conductivity and fatigue resistance according to any one of claims 1-5 is coated with an insulation layer. The aluminum alloy conductor with high conductivity and fatigue resistance according to any one of claims 1-5 is coated with an insulation layer.

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