Aluminum electrolytic anode conductive device and preparation method thereof

Abstract

The application discloses an aluminum electrolysis anode conductive device and a preparation method thereof. The preparation method of the aluminum electrolysis anode conductive device is as follows: the middle part of the upper surface of the boss is pretreated; the middle part of the upper surface of the boss is prepared with a high-entropy alloy intermediate layer by using FeCoCrNiMn high-entropy alloy wire and through a plasma arc additive manufacturing method; two parallel clamping planes are forged on the upper part of the anode aluminum guide rod with a circular cross section; and the anode aluminum guide rod is welded with the high-entropy alloy intermediate layer on the anode steel claw in a rotary friction welding mode by using a braking mode of 'first top forging and then braking'. The preparation method can improve the connecting strength between the anode aluminum guide rod and the anode steel claw, and reduce the current loss of the anode conductive device.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of anode conductive devices in the aluminum electrolysis industry, in particular to an aluminum electrolysis anode conductive device and a preparation method thereof. BACKGROUND

[0002] The anode conductive device widely used in the current aluminum electrolysis industry is composed of an upper aluminum anode aluminum guide rod and a lower steel anode steel claw. In previous studies, aluminum-steel intermetallic compounds have a great adverse effect on the aluminum / steel welding interface, and the welding reliability of the two is poor due to the difference in the expansion coefficient of steel and aluminum. The current connection method of the aluminum guide rod and the anode steel claw is to add an aluminum / steel explosive welding composite sheet as an intermediate layer between the two, and then connect the guide rod and the aluminum sheet of the composite sheet by the way of groove ring welding. Since the connection of the anode aluminum guide rod and the anode steel claw is mainly realized by the edge groove weld, the aluminum / steel contact voltage drop is poor, generally about 10 mV, and the welding strength is not ideal, and in actual production work, the two often separate.

[0003] How to improve the contact voltage drop of aluminum and steel on the basis of controlling the cost and enhance the connection strength of the anode aluminum guide rod and the anode steel claw is one of the urgent needs. Patent CN115679388A discloses a long-life energy-saving anode conductive device for aluminum electrolysis, which uses an aluminum-titanium-steel explosive welding block frame with reinforcing ribs as a component for connecting the anode guide rod and the anode steel claw, the voltage drop is low, and twelve welds on four surfaces are welded, the overall strength of the welded joint is high, but the preparation of the aluminum-titanium-steel explosive welding block frame is complex, and when welded with the guide rod and the steel claw, more welds need to be welded; Patent CN110257860A discloses a composite anode conductive device and a manufacturing method thereof, characterized by a rectangular frame composed of four composite components, the outer side of the rectangular frame is an aluminum base plate, and the inner side is a steel base plate, the connection of the steel claw and the guide rod is realized by welding the same material, this method improves the problem of hard and brittle bonding surface, but the weld cross section generates internal moment under the large gravity of the anode steel claw and the carbon block, which is easy to tear from the root of the weld and cause the claw to fall off. At the same time, this method changes the composite component from the traditional horizontal placement to the vertical placement, and due to the small constraint, the aluminum plate will have a warping trend under the large welding heat input in the actual production process, and thermal stress will be generated at the bonding surface of the aluminum plate and the steel plate, thereby reducing the strength of the composite component. SUMMARY

[0004] Therefore, the purpose of the present application is to provide an aluminum electrolysis anode conductive device and a preparation method thereof, which can improve the connection strength between the anode aluminum guide rod and the anode steel claw and reduce the current loss of the anode conductive device.

[0005] The application adopts the technical scheme that

[0006] The application discloses a preparation method of an aluminum electrolysis anode conductive device.

[0007] Step one, pretreatment is performed on the middle part of the upper surface of the boss.

[0008] Step two, an FeCoCrNiMn high-entropy alloy wire is used to prepare a high-entropy alloy intermediate layer on the middle part of the upper surface of the boss by means of a plasma arc additive manufacturing method.

[0009] Step three, at least one pair of parallel clamping planes are forged on the upper part of the anode aluminum conductor rod with a circular cross section, and then an electrolytic conductive clamp is used to clamp the anode aluminum conductor rod.

[0010] Step four, the anode aluminum conductor rod is welded to the high-entropy alloy intermediate layer on the anode steel claw in a rotary friction welding mode by using a braking mode of "first top forging and then braking".

[0011] As a preferred scheme, in step one, the specific method for pretreating the middle part of the upper surface of the boss is as follows: first, the boss is polished with sandpaper to remove burrs and oxide layers until the metal luster is exposed; then, the middle part of the upper surface of the boss is cleaned with acetone and alcohol to remove oil stains and debris.

[0012] As a preferred scheme, in step two, the thickness of the high-entropy alloy intermediate layer is greater than or equal to 15 mm.

[0013] As a preferred scheme, in step two, the preparation method of the FeCoCrNiMn high-entropy alloy wire is as follows: Fe, Co, Cr, Ni and Mn metal element wires are twisted into a cable type wire according to a molar ratio of 1:1:1:1:1, so that the FeCoCrNiMn high-entropy alloy wire is obtained.

[0014] As a preferred scheme, in step two, the specific parameters of the plasma arc additive manufacturing are as follows: the welding current is 200-260 A, the wire feeding speed is 2400-3000 mm / min, the scanning speed is 115-145 mm / min, the ion gas flow is 1.5-3.5 L / min, and the protective gas flow is 30 L / min.

[0015] As a preferred scheme, in step four, the time difference between the top forging and the braking is 0-1.2 s.

[0016] Preferably, in step four, the friction time of the rotary friction welding is 45s-70s, the rotating speed is 60-80r / min, the upsetting pressure is 70-90MPa, and the maximum upsetting force is 1350kN.

[0017] Preferably, the diameter of the anode aluminum guide rod is 100mm, and the length is 1100-1380mm.

[0018] Or;

[0019] The diameter of the anode aluminum guide rod is 130mm, and the length is 2000-2500mm.

[0020] An aluminum electrolysis anode conductive device is prepared by the method.

[0021] The design principle of the FeCoCrNiMn high-entropy alloy wire in the application is that the three elements of Fe, Co and Mn promote the solid solution transformation of the alloy, can not only control the formation of intermetallic compounds at the connecting interface, but also can play a solid solution strengthening role; the Cr element can improve the oxidation resistance and corrosion resistance of the alloy, prolong the service life of the conductive device; the Ni element can significantly improve the strength, hardness and wear resistance of the high-entropy alloy.

[0022] Advantages:

[0023] As described above, the aluminum electrolysis anode conductive device and the preparation method thereof have the following advantages:

[0024] 1) The FeCoCrNiMn high-entropy alloy interlayer is used to replace the aluminum / steel explosive welding composite welding sheet in the traditional connection method of the anode conductive device. The high-entropy effect of the high-entropy alloy controls the Fe-Al intermetallic compound at the welding interface between the high-entropy alloy interlayer and the anode aluminum guide rod, and enhances the connection strength of the welding interface.

[0025] 2) The connection method of the anode aluminum guide rod and the anode steel claw is innovated, wherein the FeCoCrNiMn high-entropy alloy interlayer is directly prepared by additive manufacturing on the boss of the anode steel claw, and the high-entropy alloy interlayer and the anode aluminum guide rod are welded by rotary friction welding. In the traditional connection method of the anode aluminum guide rod and the anode steel claw, the connection of the two is mainly completed by the edge bevel weld, and the effective connection in the middle is not realized. In the connection method of the application, the complete connection of the two interfaces is realized, which not only enhances the connection strength of the aluminum guide rod and the anode steel claw, but also reduces the contact pressure drop between aluminum and steel.

[0026] 3)、Current in the aluminum electrolysis industry anode aluminum guide pole is mostly square cross section cuboid type guide pole, the cross section of the guide pole is selected in the application The traditional guide pole is replaced, and then at least a pair of clamping planes is forged at the clamping position of the electrolytic conductive clamp. The plane structure of the clamping plane can form good electrical contact with the electrolytic conductive clamp.

[0027] The application will be further specifically and in detail described below in combination with the embodiment drawings and specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is the front view of the aluminum electrolysis anode conductive device in the application;

[0029] Figure 2 is Figure 1 side view;

[0030] Figure 3 is the principle diagram of the plasma arc additive manufacturing in the application.

[0031] The illustration mark, 1, anode aluminum guide pole, 101, clamping plane, 2, high-entropy alloy intermediate layer, 3, anode steel claw, 301, boss, 4, protective cover, 5, ion gas, 6, tungsten electrode, 7, water-cooled nozzle, 8, protective gas, 9, high-entropy alloy wire, 10, molten pool. DETAILED DESCRIPTION

[0032] The technical solutions of the application will be described in detail below in combination with the embodiments. Obviously, the described embodiments are part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the application.

[0033] A preparation method of an aluminum electrolysis anode conductive device mainly includes the following steps:

[0034] Step one: select the base area of FeCoCrNiMn high-entropy alloy intermediate layer 2 in the central area of boss 301, polish the surface of the base with 300# sandpaper first, remove burrs and oxide layers; then clean the base with acetone and alcohol to remove oil stains and debris on the surface of the base.

[0035] Step two: first select high-entropy alloy FeCoCrNiMn five kinds of component wire twisted into cable type high-entropy alloy wire 9, using plasma arc additive manufacturing method to prepare the intermediate layer, in detail, the synchronous wire feeding mechanism sends the high-entropy alloy wire 9 to the position directly below the plasma arc welding torch, and the high-entropy alloy wire 9 is in a molten state under the action of the direct current plasma arc heat source; ionized ion gas 5 enters the molten pool 10 and adheres to the surface of the molten pool 10 during the molten pool flow, and drives the flow of the molten high-entropy alloy in the molten pool 10 during the additive manufacturing process, realizing the preparation of the high-entropy alloy intermediate layer 2; wherein the tungsten electrode 6 of the welding torch is a cerium tungsten electrode with a diameter of 3.2 mm, the tungsten electrode 6 has an inner shrinkage of 2.5 mm, the water-cooled nozzle 7 has a diameter of 3.6 mm, and the distance between the tip of the high-entropy alloy wire 9 and the upper surface of the deposited layer is kept constant at 2.6 mm;

[0036] Step three: select the position where the electrolytic conductive clamp will be clamped on the cross-section circular anode aluminum guide rod 1 rotor, and then forge at least one pair of parallel clamping planes 101 at the specific position on the anode aluminum guide rod 1 rotor, and the cross-section at the clamping plane 101 of the anode aluminum guide rod 1 can be square or elliptical. Preferably, the cross-section at the clamping plane 101 is elliptical.

[0037] Step four: use the "top forging and then braking" braking mode to friction-weld the anode aluminum guide rod 1 and the high-entropy alloy intermediate layer 2 on the anode steel claw 3; wherein the top braking time difference is 0~1.2s; the friction time of the rotary friction welding is 45s~70s, the rotation speed is 60~80r / min; the top forging pressure is 70~90MPa, and the maximum top forging force is 1350kN.

[0038] Example 1

[0039] A preparation method of an aluminum electrolysis anode conductive device mainly includes the following steps:

[0040] Step one, base area pretreatment on the boss 301: select a square area in the central area of the boss 301 of the anode steel claw 3 as the base area for additive manufacturing of the FeCoCrNiMn high-entropy alloy intermediate layer 2; before additive manufacturing of the high-entropy alloy, the base area needs to be pretreated, mainly including: first, use 300# sandpaper to polish the surface of the base, remove burrs and oxidation layer, until the metal luster is exposed; then clean the base with acetone and alcohol to remove oil stains and debris on the surface of the base;

[0041] Step two, preparation of high-entropy alloy wire 9: the composition of the high-entropy alloy wire 9 is Fe: Co: Cr: Ni: Mn = 1: 1: 1: 1: 1 in mole ratio, the raw materials are selected from metal wires of corresponding elements, the purity of each raw material is not less than 99.95%, and then each metal wire is twisted into a high-entropy alloy wire 9;

[0042] Step three, preparation of high-entropy alloy intermediate layer 2: the high-entropy alloy wire 9 in step two is loaded into a synchronous wire feeding mechanism, and a high-entropy alloy intermediate layer 2 is prepared by using a plasma arc additive manufacturing system, and the specific process parameters are: scanning speed 115 mm / min, welding current: 200 A, wire feeding speed: 2400 mm / min, ion gas flow: 1.5 L / min, protective gas flow: 30 L / min, the distance between the tip of the high-entropy alloy wire 9 and the upper surface of the deposited layer is kept at 2.6 mm; in the preparation method, the ion gas 5 and the protective gas 8 are both argon;

[0043] Step four, forging clamping plane 101: two parallel clamping planes 101 are forged on the upper part of the anode aluminum guide rod 1 with a length of 1100 mm and a diameter of 100 mm, so as to facilitate the clamping of the electrolytic conductive clamp;

[0044] Step five, welding: the anode steel claw 3 and the anode aluminum guide rod 1 prepared with the high-entropy alloy intermediate layer 2 are placed on a rotary friction welding machine for friction welding, and the specific process parameters are: friction time 70 s, rotation speed 70 r / min, top brake time difference 1.2 s, top forging pressure 80 MPa, and maximum top forging force 1350 kN.

[0045] After electrical and mechanical property tests, the contact voltage drop of the anode steel claw is reduced by 5.6%, and the tensile strength of the joint is increased by 12.6% compared with the traditional preparation method.

[0046] Example 2

[0047] A preparation method of an aluminum electrolysis anode conductive device mainly includes the following steps:

[0048] Step one, pretreatment of boss 301 upper base area: select a square area in the central area of the boss 301 of the anode steel claw 3 as the base area of the additive manufacturing FeCoCrNiMn high-entropy alloy intermediate layer 2; before additive manufacturing of the high-entropy alloy, the base area needs to be pretreated, mainly including: first, use 300# sandpaper to polish the surface of the base, remove burrs and oxide layers, and expose the metal luster until the metal luster is exposed; then clean the base with acetone and alcohol to remove oil stains and debris on the surface of the base;

[0049] Step two, preparation of high-entropy alloy wire 9: the composition of the high-entropy alloy wire is Fe: Co: Cr: Ni: Mn = 1: 1: 1: 1: 1 in mole ratio, the raw materials are selected from metal wires of corresponding elements, the purity of each raw material is not less than 99.95%, and then each metal wire is twisted into a high-entropy alloy wire 9;

[0050] Step three, preparation of high-entropy alloy intermediate layer 2: the high-entropy alloy wire 9 in step two is loaded into a synchronous wire feeding mechanism, and a high-entropy alloy intermediate layer 2 is prepared by using a plasma arc additive manufacturing system, and the specific process parameters are: scanning speed 115 mm / min, welding current: 240 A, wire feeding speed: 2800 mm / min, ion gas flow: 3 L / min, protective gas flow: 30 L / min, the distance between the tip of the high-entropy alloy wire and the upper surface of the deposited layer is kept constant at 2.6 mm; in the preparation method, the ion gas 5 and the protective gas 8 are both argon;

[0051] Step four, forging clamping plane 101: two parallel clamping planes 101 are forged on the upper part of the anode aluminum guide rod 1 with a length of 1380 mm and a diameter of 100 mm to facilitate the clamping of the electrolytic conductive clamp;

[0052] Step five, welding: the anode steel claw 3 and the anode aluminum guide rod 1 prepared with the high-entropy alloy intermediate layer 2 are placed on a rotary friction welding machine for friction welding, and the specific process parameters are: friction time 45 s, rotation speed 150 r / min, top brake time difference 1.2 s, top forging pressure 80 MPa, and maximum top forging force 1350 kN.

[0053] After electrical and mechanical property tests, the contact voltage of the anode steel claw is reduced by 6.2%, and the tensile strength of the joint is increased by 11.2% compared with the traditional preparation method.

[0054] Example 3

[0055] A preparation method of an aluminum electrolysis anode conductive device mainly includes the following steps:

[0056] Step one, pretreatment of boss 301 base area: select a square area in the central area of the boss 301 of the anode steel claw 3 as the base area for additive manufacturing of the FeCoCrNiMn high-entropy alloy intermediate layer 2; before additive manufacturing of the high-entropy alloy, the base area needs to be pretreated, mainly including: first, use 300# sandpaper to polish the surface of the base, remove burrs and oxide layers, and expose the metal luster until the metal luster is exposed; then clean the base with acetone and alcohol to remove oil stains and debris on the surface of the base;

[0057] Step two, preparation of high-entropy alloy wire 9: the composition of the high-entropy alloy wire is Fe: Co: Cr: Ni: Mn = 1: 1: 1: 1: 1 in terms of molar ratio, the raw materials are selected from metal wires of corresponding elements, the purity of each raw material is not less than 99.95%, and then each metal wire is twisted into a high-entropy alloy wire 9;

[0058] Step three, preparation of high-entropy alloy intermediate layer 2: the high-entropy alloy wire in step two is loaded into a synchronous wire feeding mechanism, and a high-entropy alloy intermediate layer 2 is prepared by using a plasma arc additive manufacturing system, and the specific process parameters are: scanning speed 135 mm / min, welding current: 220 A, wire feeding speed: 3000 mm / min, ion gas flow: 2.5 L / min, protective gas flow: 30 L / min, the distance between the tip of the high-entropy alloy wire 9 and the upper surface of the deposited layer is kept constant at 2.6 mm; in the preparation method, the ion gas 5 and the protective gas 8 are both argon;

[0059] Step four, forging clamping plane 101: forging two parallel clamping planes 101 on the upper part of the anode aluminum guide rod 1 with a length of 2100 mm and a diameter of 130 mm to facilitate the clamping of the electrolytic conductive clamp;

[0060] Step five, welding: the anode steel claw 3 and the anode aluminum guide rod 1 prepared with the high-entropy alloy intermediate layer 2 are placed on a rotary friction welding machine for friction welding, and the specific process parameters are: friction time 70 s, rotation speed 150 r / min, top brake time difference 1.2 s, top forging pressure 90 MPa, and maximum top forging force 1350 kN.

[0061] After electrical performance and mechanical performance testing, the anode steel claw contact voltage is reduced by 4.8%, and the joint tensile strength is increased by 10.6% compared with the conventional preparation method.

[0062] The aluminum electrolysis anode conductive device and the preparation method thereof provided by the application are described in detail above, and specific examples are applied to explain the principles and specific implementation modes of the application. The above examples are only used to help understand the method and core idea of the application. It should be noted that any simple modification, equivalent change and modification made according to the technical essence of the application to the above examples by those skilled in the art falls within the protection scope of the application.

Claims

1. A method for preparing an aluminum electrolysis anode conductive device, the aluminum electrolysis anode conductive device comprising an anode aluminum guide rod and an anode steel claw, wherein the anode steel claw, from top to bottom, comprises a boss, a steel claw crossbeam, and a conductive claw disposed under the steel claw crossbeam, characterized in that, The main steps include the following: Step 1: Pre-treat the middle part of the upper surface of the boss; Step 2: Using FeCoCrNiMn high-entropy alloy wire, a high-entropy alloy intermediate layer is prepared in the middle of the upper surface of the boss by plasma arc additive manufacturing method; Step 3: Forge at least one pair of parallel clamping planes on the upper part of the anode aluminum guide rod with a circular cross-section, and then use electrolytic conductive clamps to hold the anode aluminum guide rod. Step 4: Using the "upsetting followed by braking" braking method, weld the anode aluminum guide rod to the high-entropy alloy intermediate layer on the anode steel claw by rotary friction welding; In step two, the preparation method of FeCoCrNiMn high-entropy alloy wire is as follows: Fe, Co, Cr, Ni and Mn metal elemental wires are twisted together into cable-type wires in a molar ratio of 1:1:1:1:1 to obtain FeCoCrNiMn high-entropy alloy wire.

2. The method for preparing an aluminum electrolysis anode conductive device according to claim 1, characterized in that, In step one, the specific method for pre-treating the middle part of the upper surface of the boss is as follows: First, use sandpaper to polish it to remove burrs and oxide layers until the metallic luster is exposed; then use acetone and alcohol to clean it and remove oil and debris from the middle part of the upper surface of the boss.

3. The method for preparing an aluminum electrolysis anode conductive device according to claim 1, characterized in that, In step two, the thickness of the high-entropy alloy intermediate layer is ≥15mm.

4. The method for preparing an aluminum electrolysis anode conductive device according to claim 1, characterized in that, In step two, the specific parameters for plasma arc additive manufacturing are as follows: welding current of 200~260 A, wire feed speed of 2400~3000 mm / min, scanning speed of 115~145 mm / min, ion gas flow rate of 1.5~3.5 L / min, and shielding gas flow rate of 30 L / min.

5. The method for preparing an aluminum electrolysis anode conductive device according to claim 1, characterized in that, In step four, the timing difference between the top braking and the bottom braking is 0 to 1.2 seconds.

6. The method for preparing an aluminum electrolysis anode conductive device according to claim 1, characterized in that, In step four, the friction time for rotary friction welding is 45 s to 70 s, the rotation speed is 60 to 80 r / min, the upsetting pressure is 70 to 90 MPa, and the maximum upsetting force is 1350 kN.

7. The method for preparing an aluminum electrolysis anode conductive device according to claim 1, characterized in that, The diameter of the anode aluminum guide rod is 100 mm, and the length is 1100~1380 mm; or; The diameter of the anode aluminum guide rod is 130 mm, and the length is 2000~2500 mm.

8. A conductive device for an aluminum electrolysis anode, characterized in that, It is prepared by the method described in any one of claims 1-7.

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