CN111826558A - A kind of aluminum-magnesium-silicon alloy monofilament and preparation method thereof - Google Patents

Abstract

The present invention provides an aluminum-magnesium-silicon alloy monofilament and a preparation method thereof. The alloy monofilament comprises in mass percentage: magnesium: 0.50-0.70%, silicon: 0.30-0.50%, erbium: 0.30-0.50 %, lanthanum (cerium): 0-0.08%, boron: 0.01-0.02%, impurity elements vanadium + titanium + chromium + manganese ≤ 0.01%, the rest are aluminum and inevitable impurities. The monofilament preparation method includes: smelting, refining, casting, rolling, wire drawing and aging treatment. The present invention obtains the electrical conductivity ≥56% IACS (20° C.), the tensile strength ≥300MPa, Aluminum alloy monofilament with elongation ≥3.0%.

Description

A kind of aluminum-magnesium-silicon alloy monofilament and preparation method thereof

technical field

The invention relates to an electrical conductor material, in particular to a design and an aluminum alloy monofilament.

Background technique

With the rapid development of industry, the demand for electricity is rising year by year. The comprehensive performance of overhead wires as an important carrier of power transmission in the power grid directly affects the safety of power transmission and the efficiency of energy transmission. High-strength overhead conductors can not only ensure the safe operation of conductors in harsh service environments such as icing and wind load, but also have high electrical conductivity, which can improve the power transmission efficiency of transmission lines and reduce transmission losses.

Aluminum-magnesium-silicon alloys are the preferred materials for long-distance and large-span transmission lines due to their low alloying degree, high specific strength, good mechanical and electrical conductivity, and high corrosion resistance. However, the conductivity of the existing aluminum-magnesium-silicon alloy wires is low, and it is difficult to meet the transmission requirements of energy saving and loss reduction.

Therefore, it is necessary to provide an aluminum-magnesium-silicon alloy wire material with high strength and high electrical conductivity.

Invention content:

The purpose of the present invention is to prepare a high-strength and high-conductivity aluminum-magnesium-silicon alloy monofilament material using electrical aluminum ingots with a purity of 99.7% as a raw material to meet the needs of the prior art.

The invention improves the microstructure and comprehensive properties of the alloy by adding trace amounts of erbium, lanthanum (cerium), boron elements and corresponding preparation processes, and obtains electrical conductivity ≥ 56% IACS (20° C.), tensile strength ≥ 300MPa, elongation ≥3.0% aluminum alloy monofilament.

The technical solutions for implementing the above purpose are as follows:

An aluminum-magnesium-silicon alloy monofilament, which is improved in that the alloy monofilament comprises the following components by mass percentage:

Magnesium: 0.50～0.70%, Silicon: 0.30～0.50%, Erbium: 0.30～0.50%, Lanthanum (Cerium): 0～0.08%, Boron: 0.01～0.02%, Impurity elements vanadium+titanium+chromium+manganese≤0.01% , the rest is aluminum and inevitable impurities.

Among them, erbium is 0.30 to 0.50%, lanthanum (cerium) is 0 to 0.08%, and boron is 0.01 to 0.02%.

Wherein, the preparation process of the monofilament includes: smelting aluminum ingots with a purity higher than a preset purity threshold in a smelting furnace at 730-750°C;

Adding aluminum-lanthanum master alloy, aluminum-cerium master alloy or lanthanum-cerium mixed rare earth to the obtained melt at 730-740° C., and adding aluminum-boron master alloy, after melting, let stand for the first time to remove impurities;

Add pure magnesium, aluminum-silicon master alloy and aluminum-erbium master alloy to the melt that has been left to stand for impurity removal at 730-750°C, melt and stir, and then let stand for a second time to remove impurities;

Blowing nitrogen with a pressure of 0.5-0.8 MPa into the melt at 710-730°C, leaving it for a third time and removing the slag;

Pour the melt at 700-720°C into a metal mold to obtain an ingot;

Rolling or extruding the ingot at 510-530°C for 1-2h into a rod with a diameter of 9.5mm, water quenching and wire drawing.

Wherein, the rolling of the ingot is continuous casting and rolling, and the continuous casting and rolling includes that the temperature of the molten liquid obtained by the slag skimming is 510-530 °C, and the final rolling temperature is not lower than 400 °C, The cooling liquid is cooled, and the rod is pulled out at 90-100 ℃ to obtain the rod.

Wherein, the extrusion includes: extruding the ingot obtained by casting the melt after slag removal at a temperature of 510-530°C, extruding at a temperature not lower than 400°C, cooling with a cooling liquid, and cooling at a temperature of 90-100°C Down the pole, get the pole material.

Wherein, the rod is drawn through 8 to 12 passes to obtain a monofilament of φ3 to 4 mm; and the monofilament is aged at 175 to 190° C. for 6 to 10 hours to obtain an aluminum-magnesium-silicon alloy monofilament.

Wherein, the standing for the first time to remove impurities includes: standing for 40-60 min, pouring 4/5 of the solution from the upper part of the smelting furnace into another holding furnace to obtain a solution for standing and removing impurities.

Wherein, the second time is 15-20 minutes; the third time is 20-30 minutes.

The stirring time and the nitrogen blowing time were both 10-15 min.

Among them, aluminum ingots with a purity higher than a preset purity threshold are smelted in a smelting furnace at 730-750 °C;

Adding aluminum-lanthanum master alloy, aluminum-cerium master alloy or lanthanum-cerium mixed rare earth to the obtained melt at 730-740° C., and adding aluminum-boron master alloy, after melting, let stand for the first time to remove impurities;

Add pure magnesium, aluminum-silicon master alloy and aluminum-erbium master alloy to the melt that has been left to stand for impurity removal at 730-750°C, melt and stir, and then let stand for a second time to remove impurities;

Blowing nitrogen with a pressure of 0.5-0.8 MPa into the melt at 710-730°C, leaving it for a third time and removing the slag;

Pour the melt at 700-720°C into a metal mold to obtain an ingot;

的杆材，水淬和拉丝，得到下述组分的铝-镁-硅合金单丝：镁:0.50～0.70％，硅:0.30～0.50％，铒:0.30～0.50％，镧(铈):0～0.08％，硼:0.01～0.02％，杂质元素钒+钛+铬+锰≤0.01％，其余为铝和不可避免的杂质。Rolling or extruding the ingot at 510-530℃ for 1-2h

The rod material is water quenched and drawn to obtain an aluminum-magnesium-silicon alloy monofilament with the following composition: magnesium: 0.50-0.70%, silicon: 0.30-0.50%, erbium: 0.30-0.50%, lanthanum (cerium): 0~0.08%, boron: 0.01~0.02%, impurity elements vanadium + titanium + chromium + manganese ≤ 0.01%, the rest are aluminum and inevitable impurities.

Compared with the closest prior art, the technical scheme provided by the present invention has the following beneficial effects:

The magnesium in the technical solution provided by the present invention has an obvious strengthening effect on aluminum, and the tensile strength of the obtained product increases by about 34 MPa for every 1% increase of magnesium. In aluminum-magnesium-silicon alloys, the strengthening phase magnesium silicide plays a role in strengthening the alloy; and the strengthening phase of magnesium silicide also has a certain influence on the electrical conductivity of the alloy. When the magnesium content is low, the electrical conductivity of the alloy is generally high and the strength is low, but a moderate excess of magnesium can fully precipitate magnesium silicide after heat treatment, and it is also beneficial to the improvement of the electrical conductivity of the alloy.

As one of the most common elements of aluminum alloy, silicon in the technical solution of the present invention can form some compounds in the alloy, so that the aluminum alloy can be heat treated, the castability and welding fluidity of the aluminum alloy are improved, and the aluminum alloy has a relatively high performance. High mechanical properties.

The rare earth element erbium can significantly improve the strength of the aluminum alloy. Not only that, the addition of erbium can also reduce the dendrite segregation of the aluminum alloy, and can significantly refine the grain structure of the alloy. When the content is low, it conforms to the traditional rare earth refining mechanism. When the erbium content is high, due to the formation of primary aluminum ₃ erbium particles in the melt, it can be used as a heterogeneous nucleation core during crystallization, thereby significantly refining Grain structure; in addition, erbium can also react with some impurity elements in the aluminum alloy to transform the impurity elements from the atomic state to the precipitation state, thereby improving the electrical conductivity of the aluminum alloy.

The technical scheme of the present invention is to select rare earths from lanthanum, cerium or lanthanum-cerium mixed rare earths, which can purify the alloy liquid, change the impurity elements such as iron and silicon from solid solution atoms into the second phase, reduce lattice distortion, and improve aluminum alloys. Electrical conductivity of alloys.

The boron in the technical scheme of the present invention can react with the transition group components of chromium, manganese, vanadium and titanium as impurity elements, so that it is transformed from a solid solution state to a compound state and deposited at the bottom of the melt, thereby improving the electrical conductivity of the aluminum alloy. performance, the boride treatment provided by the present invention can be regarded as an effective method for reducing the impurities of the aluminum alloy.

Furthermore, vanadium, manganese, chromium and titanium in the technical solution of the present invention are all impurity elements in the aluminum alloy, which have a great influence on the electrical conductivity of the aluminum alloy. When the impurity elements such as titanium, vanadium, manganese, and chromium in the aluminum alloy conductor exist in a solid solution state, it is easy to absorb the free electrons in the conductor material and fill their incomplete electronic layers, reducing the number of conduction electrons and causing the aluminum alloy conductor to conduct electricity. Sexual reduction. It was found that every 1% increase in the content of (chromium + titanium + manganese + vanadium) has a detrimental effect on the conductivity of aluminum, which is equivalent to 5 times that of silicon for every 1% increase in silicon. In the technical scheme of the present invention, strictly controlling the content of these elements plays an important role in ensuring the quality of the aluminum conductor.

In the technical solution provided by the present invention, the rare earth elements erbium, lanthanum (cerium) and boron are added to the aluminum-magnesium-silicon alloy, and a corresponding aging treatment process is adopted to make some impurity atoms generate a second phase and remove it by precipitation, and then adopt Corresponding aging treatment precipitates molten atoms, which not only strengthens but also reduces lattice distortion, thereby improving electrical conductivity. Aluminum alloy monofilament with elongation ≥3.0%.

Specific implementation plan:

The technical solutions provided by the present invention will be described in detail below by way of specific embodiments.

"From the upper part of the smelting furnace" means taking out the melt in the "upper part of the smelting furnace" to another holding furnace.

The electrical conductivity of each embodiment of the present application is based on performance testing according to the requirements of GB/T 23308 aluminum-magnesium-silicon alloy round wire for overhead stranded wires. The tensile strength was measured by Sansi CMT6104 computer-controlled electronic universal testing machine.

Example 1

An aluminum-magnesium-silicon alloy monofilament, its components and their mass percentages are:

element magnesium silicon erbium Lanthanum (Cerium) boron Vanadium + Titanium + Chromium + Manganese aluminum Mass fraction/wt.% 0.50 0.30 0.50 0.08 0.01 0.01 margin

Add the electrical pure aluminum ingot with a purity of 99.7% into the smelting furnace at 730℃ for melting;

After melting, add aluminum-lanthanum master alloy and aluminum-boron master alloy at 740°C, stir fully after melting, and let stand for 40 minutes;

From the upper part of the melting furnace, pour 4/5 of the melt into another holding furnace, add pure magnesium, aluminum-silicon master alloy, and aluminum-erbium master alloy at 730 ° C, stir for 15 minutes after complete melting, and let stand for 15 minutes;

Blow into nitrogen at 0.5-0.8MPa for 15min at 715℃, and then slag slag after standing for 20min;

Pour the aluminum alloy liquid at 700°C into the metal mold to obtain an ingot of 22×22×200mm;

The ingot kept at 510°C for 2h was rolled into an aluminum alloy rod of φ9.5mm, and then rapidly water-quenched. After 8 passes of drawing, the φ4mm aluminum alloy monofilament was obtained and then kept at 175°C for 10h to obtain aluminum-magnesium. -Silicon alloy monofilament, the conductivity of the monofilament is 56.2% IACS (20°C), the tensile strength is 307MPa, and the elongation is 3.2%.

Example 2

An aluminum-magnesium-silicon alloy monofilament, the mass percentage of each component is:

element magnesium silicon erbium Lanthanum (Cerium) boron Vanadium + Titanium + Chromium + Manganese aluminum Mass fraction/wt.% 0.70 0.50 0.40 0.05 0.015 0.008 margin

Electrically pure aluminum ingots with a purity of 99.7% are put into the melting furnace, and the melting temperature is 750 ° C; after the pure aluminum is completely melted, the aluminum-cerium master alloy is added at 730 ° C and the aluminum-boron master alloy is added at the same time, and it is fully melted and fully stirred. , let stand for 50min; pour the upper aluminum liquid of 4/5 of the melting furnace into another holding furnace, add pure magnesium, aluminum-silicon master alloy, aluminum-erbium master alloy at 750℃, stir for 10min after complete melting, and let stand for 20min . Make their final contents as shown above. At 720°C, blow in nitrogen gas of 0.5-0.8MPa for 10min, and let it stand for 30min before removing the slag. The aluminum alloy liquid was poured into a metal mold at 710° C. to obtain an ingot of 22×22×200 mm. The ingot is kept at 520°C for 1.5h, rolled into an aluminum alloy round rod with a diameter of 9.5mm, and then rapidly water quenched. After 10 times of drawing, the φ3.5mm aluminum alloy monofilament was obtained and kept at 185°C for 8h. The conductivity of the monofilament was 56% IACS (20°C), the tensile strength was 311MPa, and the elongation was 3.0%.

Example 3

An aluminum-magnesium-silicon alloy monofilament, the mass percentage of each component is:

element magnesium silicon erbium Lanthanum (Cerium) boron Vanadium + Titanium + Chromium + Manganese aluminum Mass fraction/wt.% 0.60 0.40 0.30 0.04 0.02 0.007 margin

Electrically pure aluminum ingots with a purity of 99.7% were put into the melting furnace, and the melting temperature was 740°C; after the pure aluminum was completely melted, lanthanum-cerium mixed rare earth was added at 735°C and an aluminum-boron master alloy was added at the same time. , let stand for 50min; pour the upper aluminum liquid of 4/5 of the melting furnace into another holding furnace, add pure magnesium, aluminum-silicon master alloy, aluminum-erbium master alloy at 740 ℃, stir for 15min after complete melting, and let stand for 20min . Make their final contents as shown above. At 730°C, blow in nitrogen gas of 0.5-0.8MPa for 15min, let it stand for 25min and then remove the slag. The aluminum alloy liquid was poured into a metal mold at 720° C. to obtain an ingot of 22×22×200 mm. The ingot is kept at 530℃ for 1h, rolled into an aluminum alloy round rod with a diameter of 9.5mm, and then rapidly water quenched. After 12 times of drawing, the φ3.0mm aluminum alloy monofilament was obtained and kept at 190°C for 6h. The conductivity of the monofilament was 56.1% IACS (20°C), the tensile strength was 308MPa, and the elongation was 3.2%.

Example 4

An aluminum-magnesium-silicon alloy monofilament, its components and their weight percentages are:

element magnesium silicon erbium Lanthanum (Cerium) boron Vanadium + Titanium + Chromium + Manganese aluminum Mass fraction/wt.% 0.65 0.35 0.35 0.02 0.02 0.006 margin

Electrically pure aluminum ingots with a purity of 99.7% were put into the melting furnace, and the melting temperature was 740°C; after the pure aluminum was completely melted, lanthanum-cerium mixed rare earth was added at 735°C and an aluminum-boron master alloy was added at the same time. , let stand for 50min; pour the upper aluminum liquid of 4/5 of the melting furnace into another holding furnace, add pure magnesium, aluminum-silicon master alloy, aluminum-erbium master alloy at 740 ℃, stir for 15min after complete melting, and let stand for 20min . Make their final contents as shown above. At 730°C, blow in nitrogen with a pressure of 0.5-0.8MPa for 15min, and let it stand for 25min before removing the slag. The aluminum alloy liquid was poured into a metal mold at 720° C. to obtain an ingot of 22×22×200 mm. The ingot is kept at 530℃ for 1h, rolled into an aluminum alloy round rod with a diameter of 9.5mm, and then rapidly water quenched. After 11 times of drawing, the φ3.2mm aluminum alloy monofilament was obtained and kept at 180℃ for 9h. The conductivity of the monofilament was 56.2%IACS (20℃), the tensile strength was 305MPa, and the elongation was 3.1%.

Example 5

An aluminum-magnesium-silicon alloy monofilament, its components and their weight percentages are:

Electrically pure aluminum ingots with a purity of 99.7% are put into the smelting furnace, and the melting temperature is 750 °C; after the pure aluminum is completely melted, the aluminum-lanthanum master alloy is added at 740 °C and the aluminum-boron master alloy is added at the same time, and fully melted and fully stirred. , let stand for 45min; pour the upper aluminum liquid of 4/5 of the melting furnace into another holding furnace, add pure magnesium, aluminum-silicon master alloy, aluminum-erbium master alloy at 750℃, stir for 15min after complete melting, and let stand for 15min , so that their final contents are as shown above. At 20°C, the pressure is 0.5-0.8MPa nitrogen for 10min, and the slag is removed after standing for 30min. The aluminum alloy liquid was poured into a metal mold at 710° C. to obtain an ingot of 22×22×200 mm. The ingot was kept at 515°C for 2h, rolled into an aluminum alloy rod with a diameter of 9.5mm, and then quickly water quenched. After 9 times of drawing, the φ3.7mm aluminum alloy monofilament was obtained and kept at 185℃ for 8h.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: the present invention can still be Modifications or equivalent replacements are made to the specific embodiments of the present invention, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention shall be included within the protection scope of the claims of the present invention.

As will be appreciated by those skilled in the art, the embodiments of the present application may be provided as a method, a system, or a computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present application. It will be understood that each flow and/or block in the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to the processor of a general purpose computer, special purpose computer, embedded processor or other programmable data processing device to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing device produce Means for implementing the functions specified in a flow or flow of a flowchart and/or a block or blocks of a block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory result in an article of manufacture comprising instruction means, the instructions The apparatus implements the functions specified in the flow or flows of the flowcharts and/or the block or blocks of the block diagrams.

These computer program instructions can also be loaded on a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process that is executed on the computer or other programmable data processing apparatus execute on.

Claims (10)

1. An aluminum-magnesium-silicon alloy monofilament characterized by comprising the following components in mass percent:

0.50-0.70% of magnesium, 0.30-0.50% of silicon, 0.30-0.50% of erbium, 0-0.08% of lanthanum (cerium), 0.01-0.02% of boron, less than or equal to 0.01% of impurity elements of vanadium, titanium, chromium and manganese, and the balance of aluminum and inevitable impurities.

2. An aluminum-magnesium-silicon alloy monofilament as claimed in claim 1, wherein: 0.30 to 0.50% of erbium, 0 to 0.08% of lanthanum (cerium) and 0.01 to 0.02% of boron.

3. The aluminum-magnesium-silicon alloy monofilament as claimed in claim 1, wherein the monofilament is prepared by a process comprising:

smelting the aluminum ingot with the purity higher than a preset purity threshold in a smelting furnace at 730-750 ℃;

adding an aluminum-lanthanum intermediate alloy, an aluminum-cerium intermediate alloy or lanthanum-cerium mischmetal into the melt at 730-740 ℃, adding an aluminum-boron intermediate alloy, melting, and standing for the first time to remove impurities;

adding pure magnesium, an aluminum-silicon intermediate alloy and an aluminum-erbium intermediate alloy into the solution subjected to standing impurity removal at 730-750 ℃, melting, stirring and standing for the second time to remove impurities;

blowing nitrogen with the pressure of 0.5-0.8 MPa into the melt at the temperature of 710-730 ℃, standing for a third time and slagging off;

pouring the melt at 700-720 ℃ into a metal mold to obtain an ingot;

rolling or extruding the ingot which is kept at 510-530 ℃ for 1-2 h into a rod material with the diameter of 9.5mm, and performing water quenching and wire drawing.

4. An Al-Mg-Si alloy monofilament as claimed in claim 3,

and the ingot casting rolling is continuous casting and rolling, wherein the continuous casting and rolling comprises the steps of rolling the melt obtained by slagging off at the rolling temperature of 510-530 ℃, the finishing rolling temperature of not less than 400 ℃, cooling by using a cooling liquid, and discharging the rod at the temperature of 90-100 ℃ to obtain the rod material.

5. The aluminum-magnesium-silicon alloy monofilament as claimed in claim 3, wherein the extrusion comprises extruding an ingot obtained by casting the melt after slagging-off at 510-530 ℃ to be extruded at a temperature of not less than 400 ℃, cooling the cooling liquid, and taking out the rod at 90-100 ℃ to obtain the rod material.

6. An Al-Mg-Si alloy monofilament as claimed in claim 4 or 5,

drawing the rod material for 8-12 times to obtain a phi 3-4 mm monofilament; and

and aging the monofilament at 175-190 ℃ for 6-10 h to obtain the aluminum-magnesium-silicon alloy monofilament.

7. An Al-Mg-Si alloy monofilament as claimed in claim 3,

the standing for the first time for impurity removal comprises the following steps: standing for 40-60 min, and pouring 4/5 of the solution into another holding furnace from the upper part of the smelting furnace to obtain a solution subjected to standing and impurity removal.

8. An Al-Mg-Si alloy monofilament as claimed in claim 3,

the second time is 15-20 min; the third time is 20-30 min.

9. An Al-Mg-Si alloy monofilament as claimed in claim 3,

the stirring time and the nitrogen blowing time are both 10-15 min.

10. A preparation method of an aluminum-magnesium-silicon alloy monofilament is characterized by comprising the following steps:

smelting the aluminum ingot with the purity higher than a preset purity threshold in a smelting furnace at 730-750 ℃;

adding an aluminum-lanthanum intermediate alloy, an aluminum-cerium intermediate alloy or lanthanum-cerium mischmetal into the melt at 730-740 ℃, adding an aluminum-boron intermediate alloy, melting, and standing for the first time to remove impurities;

adding pure magnesium, an aluminum-silicon intermediate alloy and an aluminum-erbium intermediate alloy into the solution subjected to standing impurity removal at 730-750 ℃, melting, stirring and standing for the second time to remove impurities;

blowing nitrogen with the pressure of 0.5-0.8 MPa into the melt at the temperature of 710-730 ℃, standing for a third time and slagging off;

pouring the melt at 700-720 ℃ into a metal mold to obtain an ingot;

rolling or extruding the cast ingot which is kept at 510-530 ℃ for 1-2 h

The rod material is water quenched and drawn to obtain the aluminum-magnesium-silicon alloy monofilament with the following components: 0.50-0.70% of magnesium, 0.30-0.50% of silicon, 0.30-0.50% of erbium, 0-0.08% of lanthanum (cerium), 0.01-0.02% of boron, less than or equal to 0.01% of impurity elements of vanadium, titanium, chromium and manganese, and the balance of aluminum and inevitable impurities.