Preparation method of aluminum alloy wire

Abstract

The invention belongs to the technical field of overhead line transmission conductor manufacturing, and particularly relates to a preparation method of an aluminum alloy wire. According to the high-conductivity and high-strength aluminum alloy material and the matched aging process, aiming at the defects that an existing high-strength aluminum alloy wire is low in conductivity, immature in aging process, poor in surface performance and the like, by optimizing an alloy formula and the aging process, the conductivity level of the wire is remarkably improved, the process verification period is shortened, and the production cost is reduced. The production efficiency and the product consistency are improved; and meanwhile, the surface hardness and lubricity of the wire are enhanced, and construction damage and corona discharge in an operation stage are reduced, so that power transmission loss is reduced, line operation stability is improved, and electromagnetic pollution is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of overhead line transmission conductor manufacturing, and particularly relates to a method for preparing an aluminum alloy wire. Background Art

[0002] High-strength aluminum alloy conductors are mainly made of aluminum-magnesium-silicon alloy materials containing magnesium and silicon. Its 6 series products are widely used in overhead transmission line scenarios such as high drop, long distance, and large span due to their excellent tensile strength, low sag characteristics and long life. However, existing high-strength aluminum alloy conductors generally face the problem of low conductivity (only 52.5-53.0% IACS) resulting in high transmission losses. At the same time, there is a lack of mature aging processes in the development of high-conductivity aluminum alloy materials, and a lot of time is required for small sample verification to optimize process parameters, which seriously affects production efficiency. In addition, the surface hardness and lubricity of high-strength aluminum alloy single wires after aging treatment are reduced. During the line construction process, they are easily damaged due to friction with tensioners, pulleys and other equipment, which in turn affects the surface smoothness during the operation stage, aggravates the corona discharge phenomenon, and thus increases radio interference and audible noise, which has a negative impact on the surrounding environment. Summary of the Invention

[0003] To address the above-mentioned issues, the present invention aims to provide a high-conductivity, high-strength aluminum alloy material and a supporting aging process. This material addresses the shortcomings of existing high-strength aluminum alloy conductors, such as low conductivity, immature aging processes, and poor surface properties. By optimizing the alloy formulation and aging process, the conductor's conductivity is significantly improved, the process verification cycle is shortened, and production efficiency and product consistency are improved. At the same time, the conductor's surface hardness and lubricity are enhanced, construction damage and corona discharge during operation are reduced, thereby reducing transmission losses, improving line operation stability, and reducing electromagnetic pollution.

[0004] In order to solve the above-mentioned technical problems, this application provides the following technical solutions:

[0005] The present invention provides a method for preparing an aluminum alloy wire, comprising the following steps:

[0006] S11: mixing an aluminum ingot and an aluminum master alloy ingot and smelting them at a smelting temperature of 740-760° C. for 7-9 hours to obtain an aluminum alloy melt; the aluminum alloy melt is composed of the following components by weight: Si: 0.30-0.45%, Mg: 0.45-0.55%, Gd: 0.001-0.01%, Y: 0.01-0.02%, Ti: 0.005-0.008%, the total amount of Cr+Mn+V is not more than 0.001%, and the remainder is Al and unavoidable impurities;

[0007] S12: performing primary refining and double-stage filtration on the aluminum alloy melt to obtain a clean aluminum alloy melt;

[0008] S13: continuously casting and continuously rolling the clean aluminum alloy melt to obtain a high-conductivity and high-strength aluminum alloy rod;

[0009] S14: cold drawing the high-conductivity and high-strength aluminum alloy rod and allowing it to stand to obtain a semi-finished single wire with a diameter of 3-5 mm; the standing time is not less than 8 hours;

[0010] S15: performing aging treatment on the semi-finished single wire at 1.2-1.4°C / min, and cooling to room temperature (25±5°C);

[0011] In the aging treatment, when the semi-finished single wire meets the conditions of containing 0.3-0.35wt% Si and 0.45-0.48wt% Mg in its composition, a resistivity of less than 32.8nΩ·m, and a tensile strength of not less than 269MPa, the aging temperature is 143-149°C, and the aging time is 10.25-12.25h;

[0012] When the semi-finished single wire meets the conditions of containing 0.35-0.4wt% Si and 0.48-0.52wt% Mg in its composition, a resistivity of 32.2-33.4nΩ·m and a tensile strength of not less than 280MPa, the aging temperature is 149-157°C and the aging time is 9.25-11.25h;

[0013] When the semi-finished single wire meets the conditions of containing 0.4-0.45wt% Si and 0.52-0.55wt% Mg in its composition, a resistivity of not less than 32.8nΩ·m and a tensile strength of not less than 292MPa, the aging temperature is 160°C and the aging time is 9.5-12h;

[0014] S16: The cooled semi-finished single wire is cold drawn using wire drawing oil to obtain a finished aluminum alloy wire with a diameter of 2.4-4.15 mm.

[0015] Preferably, in step S11, aluminum boron 3, aluminum iron 20, magnesium ingot 100, aluminum gadolinium 20, aluminum yttrium 10, aluminum titanium 10, and aluminum titanium 3 boron 1 wire are used as aluminum intermediate alloy ingots and smelted according to the target composition ratio.

[0016] Preferably, a refining agent is used for primary refining.

[0017] Preferably, in the aging treatment of step S15, when the semi-finished single wire meets the conditions of containing 0.3-0.35wt% Si and 0.45-0.48wt% Mg in its composition, a resistivity of less than 31.8nΩ·m, and a tensile strength of 269-292MPa, the aging temperature is 143-145°C, and the aging time is 11.25-11.75h;

[0018] When the semi-finished single wire meets the conditions of containing 0.3-0.35wt% Si and 0.45-0.48wt% Mg in its composition, a resistivity of less than 31.8nΩ·m and a tensile strength of not less than 292MPa, the aging temperature is 143-145°C and the aging time is 11.75-12.25h;

[0019] In the aging treatment of step S15, when the semi-finished single wire meets the conditions of containing 0.3-0.35 wt% Si and 0.45-0.48 wt% Mg in its composition, a resistivity of 31.8-32.3 nΩ·m, and a tensile strength of 278-297 MPa, the aging temperature is 145-147° C., and the aging time is 10.25-10.75 h.

[0020] When the semi-finished single wire meets the conditions of containing 0.3-0.35wt% Si and 0.45-0.48wt% Mg in its composition, a resistivity of 31.8-32.3nΩ·m and a tensile strength of not less than 297MPa, the aging temperature is 145-147°C and the aging time is 10.75-11.25h;

[0021] When the semi-finished single wire meets the conditions of containing 0.3-0.35wt% Si and 0.45-0.48wt% Mg in its composition, a resistivity of 32.3-32.8nΩ·m and a tensile strength of 288-306MPa, the aging temperature is 147-149°C and the aging time is 11.25-11.75h;

[0022] When the semi-finished single wire meets the conditions of containing 0.3-0.35wt% Si and 0.45-0.48wt% Mg in its composition, a resistivity of 32.3-32.8nΩ·m and a tensile strength of not less than 306MPa, the aging temperature is 147-149°C and the aging time is 11.75-12.25h.

[0023] Preferably, in the aging treatment of step S15, when the semi-finished single wire meets the conditions of containing 0.35-0.4wt% Si and 0.48-0.52wt% Mg in its composition, a resistivity of 32.2-32.6 nΩ·m, and a tensile strength of 280-297 MPa, the aging temperature is 149-151° C., and the aging time is 10.25-10.75 h;

[0024] When the semi-finished single wire meets the conditions of containing 0.35-0.4wt% Si and 0.48-0.52wt% Mg in its composition, a resistivity of 32.2-32.6nΩ·m and a tensile strength of not less than 297MPa, the aging temperature is 149-151°C and the aging time is 10.75-11.25h;

[0025] When the semi-finished single wire meets the conditions of containing 0.35-0.4wt% Si and 0.48-0.52wt% Mg in its composition, a resistivity of 32.6-33nΩ·m and a tensile strength of 289-304MPa, the aging temperature is 152-154°C and the aging time is 9.25-9.75h;

[0026] When the semi-finished single wire meets the conditions of containing 0.35-0.4wt% Si and 0.48-0.52wt% Mg in its composition, a resistivity of 32.6-33nΩ·m and a tensile strength of not less than 304MPa, the aging temperature is 152-154°C and the aging time is 9.75-10.25h;

[0027] When the semi-finished single wire meets the conditions of containing 0.35-0.4wt% Si and 0.48-0.52wt% Mg in its composition, a resistivity of 33-33.4nΩ·m and a tensile strength of 295-312MPa, the aging temperature is 155-157°C and the aging time is 10.25-10.75h;

[0028] When the semi-finished single wire meets the conditions of containing 0.35-0.4wt% Si and 0.48-0.52wt% Mg in its composition, a resistivity of 33-33.4nΩ·m and a tensile strength of not less than 312MPa, the aging temperature is 155-157°C and the aging time is 10.75-11.25h.

[0029] Preferably, in the aging treatment of step S15, when the semi-finished single wire meets the conditions of containing 0.4-0.45wt% Si and 0.52-0.55wt% Mg in its composition, a resistivity of 32.8-33.5nΩ·m, and a tensile strength of 292-308MPa, the aging temperature is 160-162°C, and the aging time is 10-11h;

[0030] When the semi-finished single wire meets the conditions of containing 0.4-0.45wt% Si and 0.52-0.55wt% Mg in its composition, a resistivity of 32.8-33.5nΩ·m and a tensile strength of not less than 308MPa, the aging temperature is 160-162°C and the aging time is 11-12h;

[0031] When the semi-finished single wire meets the conditions of containing 0.4-0.45wt% Si and 0.52-0.55wt% Mg in its composition, a resistivity of 33.5-34nΩ·m and a tensile strength of 303-315MPa, the aging temperature is 162-164°C and the aging time is 9.5-10.5h;

[0032] When the semi-finished single wire meets the conditions of containing 0.4-0.45wt% Si and 0.52-0.55wt% Mg in its composition, a resistivity of 33.5-34nΩ·m and a tensile strength of not less than 315MPa, the aging temperature is 162-164°C and the aging time is 10.5-11.5h;

[0033] When the semi-finished single wire meets the conditions of containing 0.4-0.45wt% Si and 0.52-0.55wt% Mg in its composition, a resistivity of not less than 34nΩ·m and a tensile strength of 311-326MPa, the aging temperature is 164-166°C and the aging time is 10-11h;

[0034] When the semi-finished single wire meets the conditions of containing 0.4-0.45wt% Si and 0.52-0.55wt% Mg in its composition, a resistivity of not less than 34nΩ·m and a tensile strength of not less than 326MPa, the aging temperature is 164-166°C and the aging time is 11-12h.

[0035] Preferably, the time for the first refining is 30-40 minutes.

[0036] Preferably, in step S13, the continuous casting temperature is 680-690°C, the casting speed is 4.5-5t / h, the cooling water temperature is 20-35°C, and the billet discharge temperature is 450-470°C.

[0037] Preferably, in step S13, during continuous rolling, the temperature of the starting rolling is 505-525°C, and the temperature of the finishing rolling is 60-80°C.

[0038] Preferably, in step S15, the wind speed during cooling is 8-13 m / s, the wind temperature is 10-15° C., and the cooling rate is 0.8-1.0° C. / min.

[0039] Preferably, in the step S14, cold drawing is performed through 7-10 dies, and the die extension coefficient is 1.29-1.32; in the step S16, cold drawing is performed through 1-2 dies, and the die extension coefficient is 1.24-1.26.

[0040] Preferably, in step S16, the electrical conductivity of the single wire decreases by no more than 0.5% after cold drawing, and the tensile strength and surface hardness are respectively increased by more than 1.3%.

[0041] Specifically, the preparation method of the aluminum alloy wire comprises the following steps:

[0042] ① Aluminum alloy material composition and continuous casting and rolling

[0043] Composition design: The mass percentages of added alloying elements are: Si: 0.30-0.45%, Mg: 0.45-0.55%, Gd: 0.001-0.01%, Y: 0.01-0.02%, Ti: 0.005-0.008%, Cr+Mn+V: ≤0.001%, and the rest are Al and unavoidable impurities.

[0044] The preparation method of the high-conductivity and high-strength aluminum alloy rod is as follows: smelting, refining, casting and rolling.

[0045] Melting: According to the target composition, aluminum ingots and aluminum master alloy ingots of corresponding weight are mixed and put into the melting furnace for melting to ensure the precise control of the alloy composition.

[0046] Refining: The aluminum alloy melt is refined once with a refining agent, which has a good degassing and impurity removal effect. After standing for 30-40 minutes, it is then subjected to double-stage filtration through a degassing box and a filter box to effectively remove gas and impurities in the melt and improve the purity of the aluminum alloy melt.

[0047] Casting: The refined clean aluminum alloy melt is continuously cast, the casting temperature is strictly controlled at 680-690℃, the casting speed is maintained at 4.5-5.0t / h, the cooling water temperature is maintained at 20-35℃, and the billet temperature is controlled at 450-470℃.

[0048] Rolling: The ingot is continuously rolled, the feed temperature is controlled at 505-525℃, and the final rolling temperature is strictly maintained at 60-80℃, and finally a high conductivity and high strength aluminum alloy rod is obtained.

[0049] ②High conductivity and high strength aluminum alloy rod wire treatment

[0050] High-conductivity, high-strength aluminum alloy rods are cold-drawn through a high-speed aluminum alloy wire drawing machine with 7-10 precision dies, using a die-matching elongation coefficient of 1.29-1.32. Precisely controlled process parameters successfully produce semi-finished, high-conductivity, high-strength aluminum alloy wires with diameters of 3.00-5.00mm (hereinafter referred to as semi-finished wires). After drawing, the wires must rest for at least 8 hours to ensure stable material properties before moving on to the next process.

[0051] ③Single-line aging treatment of semi-finished products

[0052] Based on the gradient range of key alloying element content in aluminum alloy materials and the range of resistivity and tensile strength of semi-finished single wires, the influence of aging process temperature and time on material strengthening is deeply analyzed from the perspective of alloying element composition, organization and mechanism. Through research, it is found that aging treatments at different temperatures and times will significantly affect the precipitation behavior of alloying elements and the formation of precipitated phases, thereby changing the resistivity and tensile strength of semi-finished single wires. Based on this, a new and differentiated aging process has been developed, which can take into account the resistivity and tensile strength of the material and achieve an optimal balance between the two. Specifically, by precisely controlling the aging temperature and aging time, the precipitation of alloying elements can be adjusted to promote the Mg-containing 、 The formation and growth of a supersaturated solid solution of Si element (also known as beneficial phase) ensures that the semi-finished single wire has high tensile strength while reducing the resistivity and improving the comprehensive performance of the material to meet the performance requirements of aluminum alloy materials in different application scenarios.

[0053] In step one, to ensure stable heating and uniform heat treatment of the semi-finished product, the aging heating rate was set at 1.2-1.4°C / min until the target aging temperature was reached. Precisely controlling the heating rate effectively regulates the evolution of the material's internal structure, promoting the precipitation and uniform distribution of beneficial phases.

[0054] Step 2: According to the content of key alloy elements and the resistivity and tensile strength range of the semi-finished single wire, the corresponding aging time and aging temperature are matched (see Table 1 for details) to achieve precise performance control.

[0055] Table 1 Aging process

[0056]

[0057] Step three: Place the aging-treated semi-finished product strands into a sealed, 5-meter-long, 15-meter-wide, and 3-meter-high box divided into four cooling zones. Each zone is equipped with a four-sided, eight-ducted air circulation system. Air speeds are strictly controlled at 8-13 m / s, and air temperatures are maintained at 10-15°C. This allows for a precise cooling rate of 0.8-1.0°C / min down to room temperature, ensuring uniform and stable cooling of the semi-finished strands and guaranteeing consistent and stable material performance.

[0058] After the above-mentioned process, the performance of the semi-finished single wire is significantly improved, the conductivity is stably reached 56.13% IACS and above, the tensile strength is as high as 296 MPa and above, and the surface hardness reaches 98 HB and above.

[0059] ④Semi-finished single-wire pulling wire

[0060] Using a high-power, high-speed aluminum alloy wire drawing machine, semi-finished single wires are cold-drawn through one or two dies, with the die elongation coefficient precisely controlled at 1.24-1.26. This produces finished, high-conductivity, high-strength aluminum alloy single wires (referred to as finished single wires) with a diameter of 2.40-4.15mm. The drawing process is completed with full lubrication using wire drawing oil, ensuring that the wire conductivity decreases by no more than 0.5%, while simultaneously increasing tensile strength and surface hardness by over 1.3%. The wire drawing oil re-forms a uniform lubricating film on the wire surface, enhancing both lubrication and anti-oxidation properties, significantly reducing the risk of surface damage caused by friction during the stranding and construction stages.

[0061] The final finished product has a single-wire conductivity of over 55.85% IACS, a tensile strength of no less than 300 MPa, a surface hardness of 99 HB or above, and a smooth surface with a uniform lubricating oil film, ensuring excellent electrical performance, mechanical strength, and durability in subsequent applications, meeting the stringent material performance requirements of high-end transmission line projects.

[0062] The present invention also provides a high-conductivity and high-strength aluminum alloy conductor strand, which is obtained by segmentally concentrically stranding multiple coils of aluminum alloy wire prepared by the above preparation method.

[0063] The technical solution of the present invention has the following advantages over the prior art:

[0064] The present invention provides a high-conductivity, high-strength aluminum alloy material and a supporting aging process, effectively addressing the low conductivity, immature aging process, and poor surface properties of existing high-strength aluminum alloy conductors. By precisely controlling the alloying element content, adding elements such as Si, Mg, Gd, Y, and Ti, and controlling impurities, a unique alloy system is constructed. Using processes including smelting, refining, casting, and rolling, and strictly controlling parameters at each stage, a high-conductivity, high-strength aluminum alloy rod is successfully produced. During the wire drawing process, a high-speed wire drawing machine and multi-pass die are used to cold-draw the semi-finished wire, which is then stabilized by standing. Regarding the aging process, the influence of aging parameters on the material is analyzed based on the content of key elements and the performance of the semi-finished wire. A differentiated new aging process is developed to optimize material properties. During the cooling process, a wind circulation system precisely controls the cooling rate to ensure consistent performance. The resulting finished wire exhibits excellent conductivity, tensile strength, and surface hardness, and its surface is smooth and coated with a lubricating oil film, meeting the requirements of high-end power transmission line projects. DETAILED DESCRIPTION

[0065] The present invention will be further described below with reference to specific examples so that those skilled in the art can better understand the present invention and implement it, but the examples are not intended to limit the present invention.

[0066] Example 1:

[0067] ① Aluminum alloy material composition and continuous casting and rolling

[0068] Composition design: The mass percentages of added alloying elements are: Si: 0.44%, Mg: 0.54%, Gd: 0.007%, Y: 0.02%, Ti: 0.006%, Cr+Mn+V: 0.0005%, and the rest are Al and unavoidable impurities.

[0069] The preparation method of the high-conductivity and high-strength aluminum alloy rod is as follows: smelting, refining, casting and rolling.

[0070] Melting: According to the target composition, aluminum ingots and aluminum master alloy ingots of corresponding weight are mixed and put into the melting furnace for melting to ensure the precise control of the alloy composition.

[0071] Refining: The aluminum alloy melt is refined once using a refining agent (the manufacturer of the refining agent is Hunan Jinlianxing Special Materials Co., Ltd., and the model is GFLUX granular fusion refining agent). The refining agent has a good degassing and impurity removal effect. After standing for 36 minutes, it is filtered in two stages through a degassing box and a filter box to effectively remove gas and impurities in the melt and improve the purity of the aluminum alloy melt.

[0072] Casting: The refined clean aluminum alloy melt is continuously cast, the casting temperature is strictly controlled at 688℃, the casting speed is maintained at 4.6t / h, the cooling water temperature is maintained at 31℃, and the billet temperature is controlled at 463℃.

[0073] Rolling: The ingot is continuously rolled, the feed temperature is controlled at 522°C, and the final rolling temperature is strictly maintained at 68°C, and finally a high-conductivity and high-strength aluminum alloy rod is obtained.

[0074] ②High conductivity and high strength aluminum alloy rod wire treatment

[0075] High-conductivity, high-strength aluminum alloy rods are cold-drawn through a high-speed aluminum alloy wire drawing machine with eight precision dies, using a die-matching elongation coefficient of 1.30. Precisely controlled process parameters successfully produce semi-finished, high-conductivity, high-strength aluminum alloy single wires with a diameter of 3.33mm (hereinafter referred to as semi-finished single wires). After drawing, the single wires are left to rest for nine hours to ensure stable material properties before moving on to the next process.

[0076] ③Single-line aging treatment of semi-finished products

[0077] In step one, to ensure stable heating and uniform heat treatment of the semi-finished product, the aging heating rate was set at 1.3°C / min until the target aging temperature was reached. Precisely controlling the heating rate effectively regulates the evolution of the material's internal structure, promoting the precipitation and uniform distribution of beneficial phases.

[0078] Step 2: Based on the current alloying element content of 0.44wt% Si and 0.54wt% Mg, and the resistivity of the semi-finished single wire of 34.34nΩ·m and tensile strength of 331.1MPa, the corresponding aging time is determined to be 11.5h and the aging temperature is determined to be 165°C, achieving precise performance control.

[0079] Step three: Place the aging-treated semi-finished product strands into a sealed, 5-meter-long, 15-meter-wide, and 3-meter-high box divided into four cooling zones. Each zone is equipped with a four-sided, eight-ducted air circulation system. Air velocity is strictly controlled at 12 m / s, and the air temperature is maintained at 15°C. This achieves a precise cooling rate of 0.9°C / min down to room temperature, ensuring uniform and stable cooling of the semi-finished strands and guaranteeing consistent and stable material performance.

[0080] After the above-mentioned process, the performance of the semi-finished single wire is significantly improved, the conductivity is stably reached 56.32% IACS, the tensile strength is as high as 304.6MPa, and the surface hardness reaches 106.7HB.

[0081] ④Semi-finished single-wire pulling wire

[0082] Using a high-power, high-speed aluminum alloy wire drawing machine, the semi-finished wire is cold-drawn through two dies with a precisely controlled die elongation coefficient of 1.25, resulting in a finished, high-conductivity, high-strength aluminum alloy wire (referred to as the finished wire) with a diameter of 2.66mm. The drawing process is completed with ample lubrication using wire drawing oil, ensuring that the wire's conductivity decreases by no more than 0.5%, while simultaneously increasing its tensile strength and surface hardness by over 1.3%.

[0083] The final finished product has a single-wire conductivity of 56.16% IACS, a tensile strength of 312.4 MPa, a surface hardness of 110.2 HB, and a smooth surface with a uniform lubricating oil film, ensuring excellent electrical performance, mechanical strength, and durability in subsequent applications, meeting the stringent material performance requirements of high-end transmission line projects.

[0084] Example 2:

[0085] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.44 wt% Si and 0.53 wt% Mg and the resistivity of the semi-finished single wire of 34.18 nΩ·m and the tensile strength of 323.3 MPa, the corresponding aging time is determined to be 10.5 h and the aging temperature is determined to be 165° C., thereby achieving precise performance control.

[0086] The conductivity of the final finished single wire reaches above 56.27% IACS, the tensile strength reaches 308.5MPa, the surface hardness reaches 106.6HB, and the surface is smooth.

[0087] Example 3:

[0088] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.42 wt% Si and 0.53 wt% Mg and the resistivity of the semi-finished single wire of 33.84 nΩ·m and the tensile strength of 319.5 MPa, the corresponding aging time is determined to be 11.0 h and the aging temperature is determined to be 163° C., thereby achieving precise performance control.

[0089] The conductivity of the final finished single wire reaches above 56.13% IACS, the tensile strength reaches 315.6MPa, the surface hardness reaches 107.1HB, and the surface is smooth.

[0090] Example 4:

[0091] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.42 wt% Si and 0.52 wt% Mg and the resistivity of the semi-finished single wire of 33.63 nΩ·m and the tensile strength of 313.3 MPa, the corresponding aging time is determined to be 10.0 h and the aging temperature is determined to be 163° C., thereby achieving precise performance control.

[0092] The conductivity of the final finished product single wire reaches above 56.21% IACS, the tensile strength reaches 309.3MPa, the surface hardness reaches 112.4HB, and the surface is smooth.

[0093] Example 5:

[0094] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.41 wt% Si and 0.53 wt% Mg and the resistivity of the semi-finished single wire of 33.32 nΩ·m and the tensile strength of 310.0 MPa, the corresponding aging time is determined to be 11.5 h and the aging temperature is determined to be 161° C., thereby achieving precise performance control.

[0095] The conductivity of the final finished single wire reaches above 56.09% IACS, the tensile strength reaches 311.4MPa, the surface hardness reaches 110.3HB, and the surface is smooth.

[0096] Example 6:

[0097] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.41 wt% Si and 0.52 wt% Mg and the resistivity of the semi-finished single wire of 33.01 nΩ·m and the tensile strength of 301.4 MPa, the corresponding aging time is determined to be 10.5 h and the aging temperature is determined to be 161° C., thereby achieving precise performance control.

[0098] The conductivity of the final finished product single wire reaches above 56.32% IACS, the tensile strength reaches 305.5MPa, the surface hardness reaches 104.5HB, and the surface is smooth.

[0099] Example 7:

[0100] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.39 wt% Si and 0.51 wt% Mg and the resistivity of the semi-finished single wire of 33.24 nΩ·m and the tensile strength of 313.7 MPa, the corresponding aging time is determined to be 11.0 h and the aging temperature is determined to be 156° C., thereby achieving precise performance control.

[0101] The conductivity of the final finished single wire reaches above 56.17% IACS, the tensile strength reaches 307.8MPa, the surface hardness reaches 109.3HB, and the surface is smooth.

[0102] Example 8:

[0103] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.39 wt% Si and 0.50 wt% Mg and the resistivity of the semi-finished single wire of 33.11 nΩ·m and the tensile strength of 304.8 MPa, the corresponding aging time is determined to be 10.5 h and the aging temperature is determined to be 156° C., thereby achieving precise performance control.

[0104] The conductivity of the final finished single wire reaches above 55.99% IACS, the tensile strength reaches 311.2MPa, the surface hardness reaches 106.2HB, and the surface is smooth.

[0105] Example 9:

[0106] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.38 wt% Si and 0.51 wt% Mg and the resistivity of the semi-finished single wire of 32.91 nΩ·m and the tensile strength of 305.2 MPa, the corresponding aging time is determined to be 10.0 h and the aging temperature is determined to be 153° C., thereby achieving precise performance control.

[0107] The conductivity of the final finished single wire reaches above 56.31% IACS, the tensile strength reaches 306.9MPa, the surface hardness reaches 104.7HB, and the surface is smooth.

[0108] Example 10:

[0109] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.37 wt% Si and 0.50 wt% Mg and the resistivity of the semi-finished single wire of 32.77 nΩ·m and the tensile strength of 301.9 MPa, the corresponding aging time is determined to be 9.5 h and the aging temperature is determined to be 153° C., thereby achieving precise performance control.

[0110] The conductivity of the final finished product single wire reaches above 56.25% IACS, the tensile strength reaches 312.2MPa, the surface hardness reaches 108.6HB, and the surface is smooth.

[0111] Example 11:

[0112] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.36 wt% Si and 0.50 wt% Mg and the resistivity of the semi-finished single wire of 32.50 nΩ·m and the tensile strength of 299.7 MPa, the corresponding aging time is determined to be 11.0 h and the aging temperature is determined to be 150° C., thereby achieving precise performance control.

[0113] The conductivity of the final finished single wire reaches above 56.13% IACS, the tensile strength reaches 310.9 MPa, the surface hardness reaches 107.3 HB, and the surface is smooth.

[0114] Example 12:

[0115] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.35 wt% Si and 0.49 wt% Mg and the resistivity of the semi-finished single wire of 32.33 nΩ·m and the tensile strength of 292.6 MPa, the corresponding aging time is determined to be 10.5 h and the aging temperature is determined to be 150° C., thereby achieving precise performance control.

[0116] The conductivity of the final finished single wire reaches above 56.38% IACS, the tensile strength reaches 306.7MPa, the surface hardness reaches 109.1HB, and the surface is smooth.

[0117] Example 13:

[0118] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.34 wt% Si and 0.48 wt% Mg and the resistivity of the semi-finished single wire of 32.72 nΩ·m and the tensile strength of 308.9 MPa, the corresponding aging time is determined to be 12.0 h and the aging temperature is determined to be 148° C., thereby achieving precise performance control.

[0119] The conductivity of the final finished single wire reaches above 56.19% IACS, the tensile strength reaches 309.6MPa, the surface hardness reaches 110.7HB, and the surface is smooth.

[0120] Example 14:

[0121] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.35 wt% Si and 0.46 wt% Mg and the resistivity of the semi-finished single wire of 32.45 nΩ·m and the tensile strength of 301.1 MPa, the corresponding aging time is determined to be 11.5 h and the aging temperature is determined to be 148° C., thereby achieving precise performance control.

[0122] The conductivity of the final finished single wire reaches above 55.95% IACS, the tensile strength reaches 313.3MPa, the surface hardness reaches 110.0HB, and the surface is smooth.

[0123] Example 15:

[0124] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.34 wt% Si and 0.46 wt% Mg and the resistivity of the semi-finished single wire of 32.21 nΩ·m and the tensile strength of 298.5 MPa, the corresponding aging time is determined to be 11.0 h and the aging temperature is determined to be 146°C, thereby achieving precise performance control.

[0125] The conductivity of the final finished product single wire reaches above 56.02% IACS, the tensile strength reaches 309.1MPa, the surface hardness reaches 109.7HB, and the surface is smooth.

[0126] Example 16:

[0127] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.33 wt% Si and 0.47 wt% Mg and the resistivity of the semi-finished single wire of 31.97 nΩ·m and the tensile strength of 289.2 MPa, the corresponding aging time is determined to be 10.5 h and the aging temperature is determined to be 146°C, thereby achieving precise performance control.

[0128] The conductivity of the final finished single wire reaches above 56.18% IACS, the tensile strength reaches 311.2MPa, the surface hardness reaches 115.3HB, and the surface is smooth.

[0129] Example 17:

[0130] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.32 wt% Si and 0.46 wt% Mg and the resistivity of the semi-finished single wire of 31.69 nΩ·m and the tensile strength of 295.6 MPa, the corresponding aging time is determined to be 12.0 h and the aging temperature is determined to be 144° C., thereby achieving precise performance control.

[0131] The conductivity of the final finished single wire reaches above 56.27% IACS, the tensile strength reaches 309.9 MPa, the surface hardness reaches 111.7 HB, and the surface is smooth.

[0132] Example 18:

[0133] The steps are the same as those in Example 1, except that during the aging treatment of the semi-finished single wire, in step 2, based on the current alloying element content of 0.31 wt% Si and 0.45 wt% Mg and the resistivity of the semi-finished single wire of 31.48 nΩ·m and the tensile strength of 279.8 MPa, the corresponding aging time is determined to be 11.5 h and the aging temperature is determined to be 144° C., thereby achieving precise performance control.

[0134] The conductivity of the final finished single wire reaches above 56.15% IACS, the tensile strength reaches 312.8MPa, the surface hardness reaches 118.1HB, and the surface is smooth.

[0135] Application Example 1:

[0136] To produce high-conductivity, high-strength aluminum alloy conductor strands, a large-scale frame stranding machine with both pneumatic and mechanical tension control is used. The finished single wires from multiple reels of Example 1 are concentrically stranded in sections, ensuring uniform tension across each payoff reel. Combined with a preforming device and stress relief process, the strands are tightly twisted and perfectly rounded. The high surface hardness and lubricity of the finished single wires increase stranding speed by over 50%, while maintaining excellent surface quality.

[0137] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A method for preparing an aluminum alloy wire, characterized in that: The steps include: S11: mixing an aluminum ingot and an aluminum master alloy ingot, and smelting them at 740-760° C. for 7-9 hours to obtain an aluminum alloy melt; the aluminum alloy melt is composed of the following components by weight: Si: 0.30-0.45%, Mg: 0.45-0.55%, Gd: 0.001-0.01%, Y: 0.01-0.02%, Ti: 0.005-0.008%, the total amount of Cr+Mn+V is not more than 0.001%, and the remainder is Al and unavoidable impurities; S12: performing primary refining and double-stage filtration on the aluminum alloy melt to obtain a clean aluminum alloy melt; S13: continuously casting and continuously rolling the clean aluminum alloy melt to obtain a high-conductivity and high-strength aluminum alloy rod; S14: cold drawing the high-conductivity and high-strength aluminum alloy rod and allowing it to stand to obtain a semi-finished single wire with a diameter of 3-5 mm; the standing time is not less than 8 hours; S15: performing aging treatment on the semi-finished single wire at 1.2-1.4°C / min, and cooling to room temperature; In the aging treatment, when the semi-finished single wire meets the conditions of containing 0.3-0.35wt% Si and 0.45-0.48wt% Mg in its composition, a resistivity of less than 32.8nΩ·m, and a tensile strength of not less than 269MPa, the aging temperature is 143-149°C, and the aging time is 10.25-12.25h; When the semi-finished single wire meets the conditions of containing 0.35-0.4wt% Si and 0.48-0.52wt% Mg in its composition, a resistivity of 32.2-33.4nΩ·m and a tensile strength of not less than 280MPa, the aging temperature is 149-157°C and the aging time is 9.25-11.25h; When the semi-finished single wire meets the conditions of containing 0.4-0.45wt% Si and 0.52-0.55wt% Mg in its composition, a resistivity of not less than 32.8nΩ·m and a tensile strength of not less than 292MPa, the aging temperature is 160°C and the aging time is 9.5-12h; S16: The cooled semi-finished single wire is cold drawn using wire drawing oil to obtain a finished aluminum alloy wire with a diameter of 2.4-4.15 mm.

2. The preparation method according to claim 1, wherein In the aging treatment of step S15, when the semi-finished single wire meets the conditions of containing 0.3-0.35 wt% Si and 0.45-0.48 wt% Mg in its composition, a resistivity of less than 31.8 nΩ·m, and a tensile strength of 269-292 MPa, the aging temperature is 143-145° C., and the aging time is 11.25-11.75 h. When the semi-finished single wire meets the conditions of containing 0.3-0.35wt% Si and 0.45-0.48wt% Mg in its composition, a resistivity of less than 31.8nΩ·m and a tensile strength of not less than 292MPa, the aging temperature is 143-145°C and the aging time is 11.75-12.25h; In the aging treatment of step S15, when the semi-finished single wire meets the conditions of containing 0.3-0.35 wt% Si and 0.45-0.48 wt% Mg in its composition, a resistivity of 31.8-32.3 nΩ·m, and a tensile strength of 278-297 MPa, the aging temperature is 145-147° C., and the aging time is 10.25-10.75 h. When the semi-finished single wire meets the conditions of containing 0.3-0.35wt% Si and 0.45-0.48wt% Mg in its composition, a resistivity of 31.8-32.3nΩ·m and a tensile strength of not less than 297MPa, the aging temperature is 145-147°C and the aging time is 10.75-11.25h; When the semi-finished single wire meets the conditions of containing 0.3-0.35wt% Si and 0.45-0.48wt% Mg in its composition, a resistivity of 32.3-32.8nΩ·m and a tensile strength of 288-306MPa, the aging temperature is 147-149°C and the aging time is 11.25-11.75h; When the semi-finished single wire meets the conditions of containing 0.3-0.35wt% Si and 0.45-0.48wt% Mg in its composition, a resistivity of 32.3-32.8nΩ·m and a tensile strength of not less than 306MPa, the aging temperature is 147-149°C and the aging time is 11.75-12.25h.

3. The preparation method according to claim 1, wherein In the aging treatment of step S15, when the semi-finished single wire meets the conditions of containing 0.35-0.4wt% Si and 0.48-0.52wt% Mg in its composition, a resistivity of 32.2-32.6nΩ·m, and a tensile strength of 280-297MPa, the aging temperature is 149-151°C, and the aging time is 10.25-10.75h; When the semi-finished single wire meets the conditions of containing 0.35-0.4wt% Si and 0.48-0.52wt% Mg in its composition, a resistivity of 32.2-32.6nΩ·m and a tensile strength of not less than 297MPa, the aging temperature is 149-151°C and the aging time is 10.75-11.25h; When the semi-finished single wire meets the conditions of containing 0.35-0.4wt% Si and 0.48-0.52wt% Mg in its composition, a resistivity of 32.6-33nΩ·m and a tensile strength of 289-304MPa, the aging temperature is 152-154°C and the aging time is 9.25-9.75h; When the semi-finished single wire meets the conditions of containing 0.35-0.4wt% Si and 0.48-0.52wt% Mg in its composition, a resistivity of 32.6-33nΩ·m and a tensile strength of not less than 304MPa, the aging temperature is 152-154°C and the aging time is 9.75-10.25h; When the semi-finished single wire meets the conditions of containing 0.35-0.4wt% Si and 0.48-0.52wt% Mg in its composition, a resistivity of 33-33.4nΩ·m and a tensile strength of 295-312MPa, the aging temperature is 155-157°C and the aging time is 10.25-10.75h; When the semi-finished single wire meets the conditions of containing 0.35-0.4wt% Si and 0.48-0.52wt% Mg in its composition, a resistivity of 33-33.4nΩ·m and a tensile strength of not less than 312MPa, the aging temperature is 155-157°C and the aging time is 10.75-11.25h.

4. The preparation method according to claim 1, wherein In the aging treatment of step S15, when the semi-finished single wire meets the conditions of containing 0.4-0.45wt% Si and 0.52-0.55wt% Mg in its composition, a resistivity of 32.8-33.5nΩ·m, and a tensile strength of 292-308MPa, the aging temperature is 160-162°C, and the aging time is 10-11h; When the semi-finished single wire meets the conditions of containing 0.4-0.45wt% Si and 0.52-0.55wt% Mg in its composition, a resistivity of 32.8-33.5nΩ·m and a tensile strength of not less than 308MPa, the aging temperature is 160-162°C and the aging time is 11-12h; When the semi-finished single wire meets the conditions of containing 0.4-0.45wt% Si and 0.52-0.55wt% Mg in its composition, a resistivity of 33.5-34nΩ·m and a tensile strength of 303-315MPa, the aging temperature is 162-164°C and the aging time is 9.5-10.5h; When the semi-finished single wire meets the conditions of containing 0.4-0.45wt% Si and 0.52-0.55wt% Mg in its composition, a resistivity of 33.5-34nΩ·m and a tensile strength of not less than 315MPa, the aging temperature is 162-164°C and the aging time is 10.5-11.5h; When the semi-finished single wire meets the conditions of containing 0.4-0.45wt% Si and 0.52-0.55wt% Mg in its composition, a resistivity of not less than 34nΩ·m and a tensile strength of 311-326MPa, the aging temperature is 164-166°C and the aging time is 10-11h; When the semi-finished single wire meets the conditions of containing 0.4-0.45wt% Si and 0.52-0.55wt% Mg in its composition, a resistivity of not less than 34nΩ·m and a tensile strength of not less than 326MPa, the aging temperature is 164-166°C and the aging time is 11-12h.

5. The preparation method according to claim 1, wherein The time of the first refining is 30-40 minutes.

6. The preparation method according to claim 1, wherein In step S13, the continuous casting temperature is 680-690°C, the casting speed is 4.5-5t / h, the cooling water temperature is 20-35°C, and the billet outlet temperature is 450-470°C.

7. The preparation method according to claim 1, wherein In the step S13, the temperature of the continuous rolling process is 505-525°C, and the temperature of the final rolling process is 60-80°C.

8. The preparation method according to claim 1, wherein In step S15, the wind speed during cooling is 8-13 m / s, the wind temperature is 10-15° C., and the cooling rate is 0.8-1.0° C. / min.

9. The preparation method according to claim 1, wherein In the step S14, cold drawing is performed through 7-10 dies, and the die extension coefficient is 1.29-1.32; in the step S16, cold drawing is performed through 1-2 dies, and the die extension coefficient is 1.24-1.

26.

10. A high conductivity and high strength aluminum alloy stranded wire, characterized in that: The aluminum alloy wire is obtained by segmentally concentrically twisting a plurality of coils of aluminum alloy wires prepared by the preparation method according to any one of claims 1 to 9.

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