Composition Design of a High-Performance Rare Earth Aluminum Alloy Cable

Abstract

This invention discloses a compositional design for a high-performance rare-earth aluminum alloy cable, belonging to the technical field of cable conductor materials. The core of this invention lies in the quaternary synergistic microalloying of Ce, B, Zr, and Ti, combined with optimized heat treatment processes, achieving deep purification of the aluminum matrix and precise control of the second-phase morphology. The resulting cable conductor possesses high electrical conductivity (≥63% IACS), good mechanical properties (tensile strength 102~127MPa, elongation 14%~18.5%), and excellent creep resistance, fundamentally solving the technical challenge of balancing high strength and high electrical conductivity in traditional aluminum alloy cable conductors. The manufacturing process is stable, raw material costs are controllable, and it is suitable for large-scale industrial production.

Description

Technical Field

[0001] This invention relates to the field of cable conductor materials technology, and in particular to a rare-earth aluminum alloy cable for power transmission or distribution systems. Specifically, this invention relates to a composition design method that synergistically optimizes the overall performance of aluminum alloy conductors by precisely controlling the types, contents, and proportions of rare-earth elements. This design aims to solve the problem of balancing strength, conductivity, creep resistance, and processing performance in existing aluminum alloy cable materials. Background Technology

[0002] As the "blood vessels" of modern power grids, the performance of the conductor material in power cables directly determines transmission efficiency, system safety, and total life-cycle cost. For a long time, copper has been the preferred material for medium- and low-voltage power cable conductors due to its excellent conductivity and mechanical properties. However, the scarcity of copper resources and the high volatility of its price have prompted the global power industry to seek reliable solutions that "replace copper with aluminum." Aluminum alloy cables, especially 8-series (Al-Fe) aluminum alloy cables, are considered one of the most promising alternatives due to their good conductivity, low density, significant raw material cost advantages, and mature technological foundation.

[0003] As early as the mid-to-late 20th century, countries such as the United States and Canada began the research and application of aluminum alloy cables, and related products and technical standards are relatively mature. Although my country's research and application of aluminum alloy cables started later, it has developed rapidly. The state has successively included it in the industrial adjustment catalog and promulgated a series of national standards, such as "Aluminum Alloy Wire for Cable Conductors" (GB / T 30552-2014), laying the foundation for the industry's development. However, if it is to fully replace copper cables and achieve large-scale, high-reliability applications in medium and low voltage distribution networks, the existing aluminum alloy cable material system still faces severe challenges. The core problem lies in the inherent contradiction that it is difficult to synergistically improve conductivity, mechanical strength, and creep resistance.

[0004] First, according to the classic Matheson's law, the solid solution of alloying elements in an aluminum matrix causes severe lattice distortion, resulting in a significant scattering of free electrons and a sharp decrease in the material's conductivity. In pursuit of high strength, traditional formulations often tend to increase the solid solution content of reinforcing elements such as iron (Fe) and silicon (Si), which directly causes the conductivity to hover near the standard requirement's critical value (61% IACS) for a long time, making further improvement difficult. For example, the conductivity of the CK76 aluminum alloy conductor developed abroad in its early stages was only 59.5% IACS. This compromise of "trading conductivity for strength" increases line losses during long-term cable operation, contradicting the goal of building a green and low-carbon power grid.

[0005] Secondly, the reliability of aluminum alloy cables, especially their connection points, during long-term operation is another major bottleneck restricting their widespread adoption. In actual service, medium and low-voltage cables often undergo temperature cycling due to load fluctuations. Conductor joints, under high current and complex stress, are prone to high-temperature creep, leading to relaxed contact pressure, increased contact resistance, and consequently, localized overheating or even failure. Most existing research on 8-series aluminum alloys focuses on their room-temperature mechanical properties, with insufficient research on their creep behavior and microscopic mechanisms in the high-temperature range of 90℃ to 120℃. The coarse, lamellar Al3Fe phase and other brittle phases formed in traditional alloys are unevenly distributed at grain boundaries, making it difficult to effectively pin the grain boundaries at high temperatures. This results in creep resistance far inferior to copper conductors, posing a potential safety hazard to the system.

[0006] Furthermore, the research and development of aluminum alloy conductors in China once relied heavily on a trial-and-error approach, lacking systematic theoretical guidance on multi-element synergistic microalloying. Many companies, when adjusting compositions, failed to deeply understand the influence of the complex interactions between Fe, Si, Cu, Mg, and rare earth elements (RE), zirconium (Zr), and titanium (Ti) on the evolution of solute atomic clusters and the morphology and distribution of the second phase. Composition design and preparation processes (such as deformation heat treatment) were often disconnected, failing to fully utilize processing-introduced defects as nucleation sites for strengthening phases. This resulted in an inability to maximize precipitation strengthening while minimizing electron scattering.

[0007] Therefore, developing a new type of rare-earth aluminum alloy cable conductor, through precise design of rare-earth, zirconium, titanium and multi-element microalloying components, to achieve the synergy of "deep purification of the matrix" and "multi-element coherent precipitation strengthening" at the microscopic level, and fundamentally breaking the inverse relationship between conductivity and strengthening, strength and creep resistance, has become an urgent need to break through the industry's technical bottlenecks and promote the high-end application of aluminum alloy cables. Summary of the Invention

[0008] The purpose of this invention is to provide a novel rare-earth-zirconium-titanium synergistic microalloyed aluminum alloy conductor material and its composition design method. By synergistically combining specific rare-earth elements, zirconium, titanium, and elements such as Fe and Si (e.g., adding 0.02% B), the morphology and distribution of precipitated phases are precisely controlled while purifying the aluminum matrix and refining the second phase. This effectively solves the key technical problems of traditional aluminum alloy cable conductors, namely, the difficulty in achieving both high strength and high conductivity, as well as insufficient high-temperature creep resistance. Ultimately, a high-performance aluminum alloy cable with excellent conductivity (≥63% IACS), mechanical properties, and long-term connection stability is produced to meet the urgent needs of modern medium and low voltage power systems for safe, efficient, and reliable transmission.

[0009] To achieve the above objectives, the present invention provides the following technical solution: A rare-earth-zirconium-titanium synergistic microalloyed aluminum alloy cable conductor, which is composed of the following components by weight percentage: Al: Balance, Fe: 0.45%~0.60%, Si: 0.10%~0.25%, Cu: 0.08%~0.18%, Rare Earth Ce: 0.12%~0.22%, Boron (B): 0.01%~0.03%, Zr: 0.02%~0.08%, Ti: 0.01%~0.03%, Mg: 0.06%~0.12%, Zn: 0.04%~0.10%, Unavoidable Impurities: ≤0.15%.

[0010] Preferably, the composition and weight percentage of the rare earth-zirconium-titanium synergistic microalloyed aluminum alloy cable conductor are as follows: Al: balance, Fe: 0.45%~0.58%, Si: 0.10%, Cu: 0.15%, Ce: 0.16%~0.20%, B: 0.02%, Zr: 0.03%~0.05%, Ti: 0.015%~0.02%, Mg: 0.06%, Zn: 0.05%.

[0011] Furthermore, a method for preparing the rare-earth-zirconium-titanium synergistic microalloyed aluminum alloy cable conductor is provided, comprising the following steps: S1. Batching and Smelting: According to the above composition ratio, using industrial pure aluminum (such as Al070) as the base, add the corresponding amounts of Al-Fe, Al-Si, Al-Cu, Al-Ce, Al-B, Al-Zr, Al-Ti, Al-Mg master alloy and pure Zn, and smelt and stir at 720℃~750℃ to make the alloying elements uniformly distributed; S2. Refining and Purification: Refining agents (such as hexachloroethane) are added to the melt to degas and remove slag. The "purification" effect of the B element is utilized to react with harmful impurity elements such as Ti, V, and Cr in the melt to generate borides and remove them, thus purifying the aluminum matrix. S3. Casting: The refined melt is poured into a preheated mold at 710℃~730℃, and after cooling, an aluminum alloy casting rod is obtained; S4. Homogenization heat treatment: The cast rod is solution treated at 500℃~530℃ for 3~6 hours, followed by water quenching; S5. Cold deformation processing: The heat-treated cast rod is subjected to multiple cold rolling and cold drawing processes with a total deformation of ≥90% to obtain aluminum alloy hard conductors; S6. Aging annealing: The cold-deformed wire is annealed at 240℃~260℃ for 4~8 hours, and then cooled in the furnace to obtain the rare earth-zirconium-titanium synergistic microalloyed aluminum alloy cable conductor.

[0012] Preferably, the annealing process in step S6 is: annealing at 260°C for 4 hours, or annealing at 240°C for 8 hours.

[0013] The beneficial effects of this invention are as follows: Significant breakthroughs have been achieved in comprehensive performance indicators, successfully solving the problem of the "strength-conductivity" inversion. The aluminum alloy conductor prepared by this invention has a soft-state (R-state) conductivity that consistently reaches and exceeds 63.0% IACS, with a maximum of 63.2% IACS, which is superior to the national standard (≥61% IACS) and the level of traditional AA8030 aluminum alloy (approximately 60.5% IACS). At the same time, its tensile strength remains at 102-127 MPa, and its elongation is as high as 14%-18.5%, both fully meeting and exceeding the national standards and project assessment indicators. More importantly, this design, through the synergy of composition and process, achieves high strength and high conductivity while ensuring excellent plasticity, fundamentally solving the core technical bottleneck of traditional aluminum alloys that often sacrifice conductivity and plasticity to improve strength. Preliminary correlation tests show that the conductor in this composition system has excellent anti-compression creep performance at a high temperature of 130℃ and a high residual pressure retention rate, which fundamentally improves the safety and reliability of the cable under long-term current-carrying operation and solves the key pain points in the current application of aluminum alloy cables. Precise microstructure control and a clear synergistic enhancement mechanism. The superior performance of this invention stems from the precise design of the microstructure of the aluminum alloy. By introducing specific amounts of rare earth elements cerium (Ce), trace amounts of boron (B), zirconium (Zr), and titanium (Ti), multiple synergistic effects are generated: First, element B plays a deep "purification" role, reacting with transition metal impurities (such as Ti, V, Cr) in the melt that severely impair conductivity to form stable borides and remove them, greatly reducing the concentration of solute atoms in the aluminum matrix, reducing electron scattering, and laying a pure matrix foundation for high conductivity. Second, the addition of elements such as Ce, Zr, and Ti, combined with Fe, Cu, and Si, regulates the morphology and distribution of the second phase. Under the optimized aging annealing process, high-density, diffusely distributed nanoscale and submicron-scale near-spherical precipitates are formed in the alloy, while coarse and harmful lamellar phases (such as Al3Fe) are suppressed. These tiny precipitates effectively pin dislocations and hinder grain boundary slip, providing significant dispersion strengthening and second-phase strengthening effects. Thus, while increasing strength, their small size and uniform distribution result in negligible negative impacts on resistivity. Ultimately, this leads to an ideal microstructure where a near-pure aluminum matrix and a high-density nano-reinforcing phase coexist, which is the fundamental materials science reason for achieving both high strength and high conductivity. The process exhibits good adaptability and high repeatability, with controllable raw material costs. This invention preferentially uses industrial pure aluminum (such as Al070) instead of high-purity aluminum as the raw material. While significantly reducing raw material costs, the optimized composition design (especially the synergistic effect of B, Zr, and Ti) still achieves comprehensive performance surpassing that of high-purity aluminum-based alloys. The designed heat treatment regime (medium-temperature aging annealing at 240-260℃) has a clearly defined process window (e.g., 260℃×4h or 240℃×8h), facilitating precise control in industrial production. Experimental results show good performance repeatability under this process. The total addition of rare earth elements (Ce), boron (B), zirconium (Zr), and titanium (Ti) is extremely low, achieving a qualitative improvement in performance at a minimal cost, resulting in extremely high cost-effectiveness and providing a solid technical and economic foundation for large-scale industrial applications. With broad application prospects and significant socio-economic benefits, this conductor material can be directly used to manufacture 10kV and 35kV medium and low voltage aluminum alloy power cables. Its high performance can meet the urgent needs of urban power grids, photovoltaic power plants, wind power generation, and other fields for high safety, long service life, and energy conservation. Taking the improvement of conductivity as an example, every 1% increase in IACS can save approximately 1000-2500 kWh of electricity per kilometer of line per year. Therefore, promoting this high-performance aluminum alloy cable has significant social and economic value in reducing power grid transmission losses and promoting the green transformation of the energy structure. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings used in the following description are all embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0015] Figure 1 This is a table showing the alloy formulation (kg) design for the embodiments and comparative examples of the present invention.

[0016] Figure 2 This is a design table of aluminum alloy cable material composition for an embodiment of the present invention (design table of conductor composition (wt%) for rare earth microalloyed aluminum alloy cable).

[0017] Figure 3 This is a comparison of the performance test results of the embodiments and comparative examples of the present invention (Comparison Table of Performance Test Results of Embodiments and Comparative Examples).

[0018] Figure 4 This is a flowchart illustrating the manufacturing process of aluminum alloy cable material according to an embodiment of the present invention.

[0019] Figure 5 The diagram shows the conductivity of the cable materials prepared in Examples 1-7 and Comparative Examples 1-3 of this invention.

[0020] Figure 6 The tensile strength diagrams are for the cable materials prepared in Examples 1-7 and Comparative Examples 1-3 of this invention.

[0021] Figure 7 The diagram shows the elongation of the cable materials prepared in Examples 1-7 and Comparative Examples 1-3 of this invention.

[0022] Figure 8 This is a metallographic microstructure of the rare-earth cerium aluminum alloy cable material with zirconium and titanium synergistic modification according to the present invention (magnification ×1500, scale bar 30 μm). After melting and aging annealing, the alloy exhibits a uniform and refined dendritic structure with a grain size of approximately 10-15 μm. Second-phase particles formed by rare-earth cerium, zirconium, and titanium are dispersed at the grain boundaries. This microstructure characteristic reflects the synergistic refining effect of zirconium, titanium, and rare-earth cerium on the aluminum alloy matrix, which is the core structural basis for the high electrical conductivity and high tensile strength of the aluminum alloy cable material of the present invention. Detailed Implementation To enable those skilled in the art to better understand the technical solution of the present invention, the composition, preparation method, and performance of the rare-earth microalloyed aluminum alloy cable conductor of the present invention will be described in detail below with reference to specific embodiments and comparative examples. The following embodiments are only used to explain the present invention and are not intended to limit the present invention. I. Raw Materials The main raw materials used in the examples and comparative examples are as follows: Base metal: Industrial pure aluminum A1070 ingot (purity ≥99.7%), or high-purity aluminum (Al ≥99.9%) for reference; Master alloys: Al-10Fe, Al-20Si, Al-50Cu, Al-10Ce, Al-8B, Al-10Zr, Al-10Ti, Al-10Mg master alloys; Pure metal: Pure zinc (Zn≥99.9%); Refining agent: hexachloroethane (C2Cl6, reagent grade). II. General Steps in the Preparation Process The general manufacturing process of the aluminum alloy conductor of this invention is as follows, and the specific parameters are detailed in each embodiment: S1. Batching and Melting: Weigh the raw materials according to the designed proportions. Heat the industrial pure aluminum in a resistance furnace to 750℃ until it is completely melted, and hold for 10 minutes. Add the required intermediate alloys and pure zinc in sequence, mechanically stirring for 5 minutes after each addition, and letting it stand for 5 minutes to ensure uniform alloying elements; S2. Refining and Purification: Add 1% hexachloroethane refining agent by weight of the molten aluminum, stir for 5 minutes, let stand, and remove slag. In this step, the boron (B) element contained in the Al-B master alloy reacts with transition metal impurities (such as Ti, V, Cr, etc.) in the melt that are harmful to conductivity to form borides that float to the surface, thus purifying the matrix. S3. Casting: The temperature of the refined melt is reduced to 720℃ and held for 15 minutes. Then it is poured into a metal mold preheated to 300℃ and allowed to cool naturally in the air to obtain a cylindrical aluminum alloy casting rod with a diameter of 20mm. S4. Homogenization heat treatment (solution treatment): Place the cast rod in a box furnace and hold it at 520℃ for 5 hours, followed by water quenching; S5. Cold Deformation Processing: The solution-quenched ingot is subjected to multiple cold rolling and cold drawing processes. The total cold deformation is ≥90%, ultimately yielding an aluminum alloy hardened (Y-state) conductor with a diameter of approximately 3mm. S6. Aging Annealing: The cold-deformed hardened conductor is placed in a box furnace and annealed at a specified temperature for a certain time. It is then cooled to room temperature with the furnace to obtain a soft (R-state) aluminum alloy cable conductor. This step is crucial for performance determination. III. Examples and Comparative Examples Example 1: Alloy composition (wt%): Al-0.58Fe-0.1Si-0.15Cu-0.16Ce-0.06Mg-0.05Zn-0.02B-0.03Zr-0.015Ti, with the balance being Al and unavoidable impurities. The preparation process is as follows: S1. Batching and Melting: Weigh the raw materials according to the designed proportions. Heat the industrial pure aluminum in a resistance furnace to 750℃ until it is completely melted, and hold for 10 minutes. Add the required intermediate alloys and pure zinc in sequence, mechanically stirring for 5 minutes after each addition, and letting it stand for 5 minutes to ensure uniform alloying elements; S2. Refining and Purification: Add 1% hexachloroethane refining agent by weight of the molten aluminum, stir for 5 minutes, let stand, and remove slag. In this step, the boron (B) element contained in the Al-B master alloy reacts with transition metal impurities (such as Ti, V, Cr, etc.) in the melt that are harmful to conductivity to form borides that float to the surface, thus purifying the matrix. S3. Casting: The temperature of the refined melt is reduced to 720℃ and held for 15 minutes. Then it is poured into a metal mold preheated to 300℃ and allowed to cool naturally in the air to obtain a cylindrical aluminum alloy casting rod with a diameter of 20mm. S4. Homogenization heat treatment (solution treatment): Place the cast rod in a box furnace and hold it at 520℃ for 5 hours, followed by water quenching; S5. Cold Deformation Processing: The solution-quenched ingot is subjected to multiple cold rolling and cold drawing processes. The total cold deformation is ≥90%, ultimately yielding an aluminum alloy hardened (Y-state) conductor with a diameter of approximately 3mm. S6. Aging Annealing: The cold-deformed hard conductor is placed in a box furnace and annealed at 260°C for 4 hours. Then it is cooled to room temperature with the furnace to obtain the soft (R-state) aluminum alloy cable conductor. Example 2: Alloy composition (wt%): Al-0.45Fe-0.1Si-0.15Cu-0.20Ce-0.06Mg-0.05Zn-0.02B-0.05Zr-0.02Ti, with the balance being Al and unavoidable impurities. The preparation process is as follows: S1. Batching and smelting: This step is exactly the same as in Example 1; S2. Refining and purification: This step is exactly the same as in Example 1; S3. Casting: This step is exactly the same as in Example 1; S4. Homogenization heat treatment (solution treatment): This step is exactly the same as in Example 1; S5. Cold deformation processing: This step is exactly the same as in Example 1; S6. Aging Annealing: The cold-deformed hard conductor is placed in a box furnace and annealed at 240℃ for 8 hours. Then it is cooled to room temperature with the furnace to obtain the soft (R-state) aluminum alloy cable conductor. Example 3: Alloy composition (wt%): Same as in Example 2. The preparation process steps are as follows: S1. Batching and smelting: This step is exactly the same as in Example 1; S2. Refining and purification: This step is exactly the same as in Example 1; S3. Casting: This step is exactly the same as in Example 1; S4. Homogenization heat treatment (solution treatment): This step is exactly the same as in Example 1; S5. Cold deformation processing: This step is exactly the same as in Example 1; S6. Aging Annealing: The cold-deformed hard conductor is placed in a box furnace and annealed at 260°C for 6 hours. Then it is cooled to room temperature with the furnace to obtain the soft (R-state) aluminum alloy cable conductor. Example 4: Alloy composition (wt%): Al-0.52Fe-0.25Si-0.08Cu-0.18Ce-0.09Mg-0.07Zn-0.02B-0.04Zr-0.018Ti, balance being Al and unavoidable impurities (≤0.15%). The preparation process is as follows: S1. Batching and smelting: This step is exactly the same as in Example 1; S2. Refining and purification: This step is exactly the same as in Example 1; S3. Casting: This step is exactly the same as in Example 1; S4. Homogenization heat treatment (solution treatment): This step is exactly the same as in Example 1; S5. Cold deformation processing: This step is exactly the same as in Example 1; S6. Aging Annealing: The cold-deformed hard conductor is placed in a box furnace and annealed at 250°C for 6 hours. Then it is cooled to room temperature with the furnace to obtain the soft (R-state) aluminum alloy cable conductor. Example 5: Alloy composition (wt%): Al-0.55Fe-0.15Si-0.18Cu-0.12Ce-0.12Mg-0.10Zn-0.01B-0.06Zr-0.01Ti, with the balance being Al and unavoidable impurities (≤0.15%). The preparation process is as follows: S1. Batching and smelting: This step is exactly the same as in Example 1; S2. Refining and purification: This step is exactly the same as in Example 1; S3. Casting: This step is exactly the same as in Example 1; S4. Homogenization heat treatment (solution treatment): This step is exactly the same as in Example 1; S5. Cold deformation processing: This step is exactly the same as in Example 1; S6. Aging Annealing: The cold-deformed hard conductor is placed in a box furnace and annealed at 260°C for 5 hours. Then it is cooled to room temperature with the furnace to obtain the soft (R-state) aluminum alloy cable conductor. Example 6: Alloy composition (wt%): Al-0.48Fe-0.20Si-0.12Cu-0.22Ce-0.08Mg-0.06Zn-0.03B-0.08Zr-0.03Ti, with the balance being Al and unavoidable impurities (≤0.15%). The preparation process is as follows: S1. Batching and smelting: This step is exactly the same as in Example 1; S2. Refining and purification: This step is exactly the same as in Example 1; S3. Casting: This step is exactly the same as in Example 1; S4. Homogenization heat treatment (solution treatment): This step is exactly the same as in Example 1; S5. Cold deformation processing: This step is exactly the same as in Example 1; S6. Aging Annealing: The cold-deformed hard conductor is placed in a box furnace and annealed at 240℃ for 7 hours. Then it is cooled to room temperature with the furnace to obtain the soft (R state) aluminum alloy cable conductor. Example 7: Alloy composition (wt%): completely consistent with Example 1. The preparation process steps are as follows: S1. Batching and smelting: This step is exactly the same as in Example 1; S2. Refining and purification: This step is exactly the same as in Example 1; S3. Casting: This step is exactly the same as in Example 1; S4. Homogenization heat treatment (solution treatment): This step is exactly the same as in Example 1; S5. Cold deformation processing: This step is exactly the same as in Example 1; S6. Aging Annealing: The cold-deformed hard conductor is placed in a box furnace and annealed at 240℃ for 6 hours. Then it is cooled to room temperature with the furnace to obtain the soft (R state) aluminum alloy cable conductor. Comparative Example 1: Alloy composition (wt%): Simulating traditional AA8030 aluminum alloy, the composition is Al-0.6Fe-0.3Si-0.2Cu, excluding Ce, B, Zr, and Ti. This comparative example aims to examine the influence of alloy formulation on alloy properties. Compared with Example 1, except for the different ingredient preparation in step S1, all other preparation process parameters are exactly the same. The preparation process steps are as follows: S1. Batching and smelting: This step is exactly the same as in Example 1. Depend on Figure 3 Analysis: Due to the lack of grain boundary modification by rare earth element Ce and purification effect by boron, its electrical conductivity and plasticity are lower than those of the embodiments of the present invention. The strong scattering of electrons by Fe and Si solid solution atoms leads to lower electrical conductivity. Comparative Example 2: Alloy composition (wt%): Based on Example 1, Ce, B, Zr, and Ti were removed, and the composition was adjusted to Al-0.58Fe-0.1Si-0.15Cu-0.06Mg-0.05Zn. This comparative example aims to examine the effect of the alloy formulation on the alloy properties. Except for the different ingredient preparation in step S1, the rest of the preparation process is exactly the same. The preparation process steps are as follows: S1. Batching and smelting: This step is exactly the same as in Example 1. Depend on Figure 3Analysis: Although the tensile strength is acceptable, the electrical conductivity is significantly reduced and the elongation is severely insufficient. This indicates that the lack of boron (B) purification effect results in high solid solubility of matrix impurities, severely impairing conductivity; the lack of cerium (Ce) grain boundary optimization effect leads to poor material plasticity. This demonstrates the indispensability of Ce and B in the system of this invention for achieving a synergistic improvement in "high electrical conductivity and good plasticity". Comparative Example 3: Alloy composition (wt%): Same as in Example 1. This comparative example aims to examine the influence of process parameters on alloy properties. Except for the different process parameters in step S6, the rest of the preparation process methods are exactly the same. The preparation process steps are as follows: S6. Aging Annealing: The cold-deformed hard conductor is placed in a box furnace and annealed at 220°C for 4 hours. Then it is cooled to room temperature with the furnace to obtain the soft (R-state) aluminum alloy cable conductor. Depend on Figure 3 Analysis: Insufficient annealing temperature resulted in the alloying elements failing to precipitate sufficiently and uniformly as fine, dispersed phases. A significant number of dissolved atoms remained in the matrix, which is detrimental to electrical conductivity. Simultaneously, incomplete stress relief and recrystallization led to extremely poor plasticity. This underscores the importance of the annealing temperature range of 240-260℃ in this invention.

Claims

1. A compositional design for a high-performance rare-earth aluminum alloy cable, characterized in that, During the use of this method, the chemical composition, by weight percentage, is as follows: iron (Fe): 0.45% to 0.60%, silicon (Si): 0.10% to 0.25%, copper (Cu): 0.08% to 0.18%, cerium (Ce): 0.12% to 0.22%, boron (B): 0.01% to 0.03%, magnesium (Mg): 0.06% to 0.12%, zinc (Zn): 0.04% to 0.10%, zirconium (Zr): 0.02% to 0.08%, titanium (Ti): 0.01% to 0.03%, aluminum (Al): balance, unavoidable impurities: not exceeding 0.15%.

2. The composition design of a high-performance rare-earth aluminum alloy cable according to claim 1, characterized in that, In the process of using this method, the content of cerium (Ce) is 0.16% to 0.20%, the content of boron (B) is 0.02%, the content of zirconium (Zr) is 0.03% to 0.05%, and the content of titanium (Ti) is 0.015% to 0.02%.

3. The composition design of a high-performance rare-earth aluminum alloy cable according to claim 1 or 2, characterized in that, In this method, the content of iron (Fe) is 0.45% or 0.58%, the content of silicon (Si) is 0.10%, the content of copper (Cu) is 0.15%, the content of magnesium (Mg) is 0.06%, and the content of zinc (Zn) is 0.05%.

4. The composition design of a high-performance rare-earth aluminum alloy cable according to any one of claims 1 to 3, characterized in that, During the use of this method, the electrical conductivity of the material is not less than 63.0% IACS, the tensile strength is between 102 and 127 MPa, and its elongation is not less than 14%.

5. The composition design of a high-performance rare-earth aluminum alloy cable as described in any one of claims 1 to 4, characterized in that, The method, when used, includes the following sequential steps: (1) Batching and smelting: Weigh the raw materials according to the composition ratio described in the claims, and add aluminum-iron master alloy, aluminum-silicon master alloy, aluminum-copper master alloy, aluminum-cerium master alloy, aluminum-boron master alloy, aluminum-zirconium master alloy, aluminum-titanium master alloy, aluminum-magnesium master alloy and pure zinc in sequence, using industrial pure aluminum as the base; smelt in a temperature range of 720°C to 750°C, and stir to make each alloying element uniformly distributed in the aluminum melt. (2) Refining and purification: A refining agent is added to the aluminum melt and stirred thoroughly to remove gas and impurities; wherein, the boron element contained in the aluminum-boron master alloy can react with the titanium, vanadium and chromium impurities in the aluminum melt to generate borides and float to the surface for removal, thereby purifying the aluminum matrix; (3) Casting: The refined and purified aluminum melt is poured into a preheated metal mold at a temperature of 710°C to 730°C, and after cooling, aluminum alloy casting rods are obtained. (4) Homogenization heat treatment: The aluminum alloy casting rod is placed in a heat treatment furnace and subjected to solution treatment at a temperature of 500°C to 530°C for 3 to 6 hours, followed by rapid water quenching. (5) Cold deformation processing: The cast rod that has undergone homogenization heat treatment is subjected to multiple cold rolling and cold drawing processes to ensure that the total deformation is not less than 90%, thereby obtaining an aluminum alloy hard conductor with a specified diameter. (6) Aging annealing treatment: The aluminum alloy hard conductor is placed in a heat treatment furnace and annealed in a temperature range of 240°C to 260°C for 4 to 8 hours. Then it is cooled to room temperature in the furnace to finally obtain the high-performance rare earth microalloyed aluminum alloy cable conductor material.

6. The preparation method according to claim 5, characterized in that, The specific process parameters for the aging annealing treatment in step (6) are selected from one of the following two processes: (a) annealing at 260°C for 4 hours; or (b) annealing at 240°C for 8 hours.

7. The preparation method according to claim 5 or 6, characterized in that, In step (2), the refining agent is hexachloroethane, and the amount added is 0.5% to 1.5% of the mass of the aluminum melt.

8. A cable, characterized in that, Its conductor portion is made of the high-performance rare-earth microalloyed aluminum alloy cable conductor material according to any one of claims 1 to 4, or the high-performance rare-earth microalloyed aluminum alloy cable conductor material prepared by the method according to any one of claims 5 to 7.

Images