A high-strength, corrosion-resistant copper-aluminum welding process, copper-aluminum parallel groove wire clamp and production equipment

Abstract

The present invention discloses a high-strength corrosion-resistant copper-aluminum welding process, a copper-aluminum parallel groove wire clamp and production equipment. The adopted technical scheme includes the following steps: Step 1: At room temperature, aluminum alloy particles are sprayed onto the local surface of a copper-nickel-silicon alloy workpiece by supersonic airflow to form an aluminum composite layer, wherein the particle size of the aluminum alloy particles is 10-14 μm; Step 2: The aluminum composite layer is welded to the copper-nickel-silicon alloy workpiece by molecular diffusion welding, the welding temperature is 500℃-600℃, and the welding pressure is 30-50MP. The advantages are as follows: the high-strength corrosion-resistant aluminum alloy material can be welded to the wire clamp groove of the high-strength corrosion-resistant clamp arm, and the interface bonding is high, and the aluminum layer is not easy to fall off.

Description

Technical Field

[0001] The invention belongs to the field of electrical equipment, and in particular relates to a power parallel groove wire clamp. Background Art

[0002] The power parallel groove clamp is a kind of hardware used in the power field, mainly used to connect two parallel wires to transmit electricity. Its structure includes: a clamp arm and a bolt assembly connected to the middle of the clamp arm, and a clamp groove is provided at both ends of the clamp arm. With the demand for copper-aluminum transition connection, the copper-aluminum parallel groove clamp was also born. The clamp arm of the traditional copper-aluminum parallel groove clamp is usually made of half copper and half aluminum welded (usually mainly by friction welding, flash welding, and brazing), the copper end is connected to the copper wire, and the aluminum end is connected to the aluminum wire to achieve the purpose of copper-aluminum transition. Its disadvantages are: poor strength and corrosion resistance, and the welding point is easy to break or corrode. In view of the above problems, the most ideal solution is: use high-strength and corrosion-resistant copper alloy materials to make the clamp arm, and then set a high-strength and corrosion-resistant aluminum alloy material in the clamp groove of the clamp arm to make an aluminum layer for connection with the aluminum wire. However, the difficulty is that it is difficult to complete the welding between high-strength and corrosion-resistant copper alloy materials and aluminum alloy materials and in arc-shaped wire clamping grooves using traditional welding technology. Even if the welding is completed by force, the aluminum layer is easy to fall off.

[0003] In addition, the applicant found through search: the Chinese invention patent with the authorization announcement number "CN202957350U" and the name "Aluminum-based hot-rolled copper-clad transition parallel groove wire clamp" uses a hot rolling process to connect thin copper sheets to the wire clamp groove of the aluminum wire clamp. The applicant has also conducted experiments on this process and found that hot rolling cannot solve the problems of galvanic corrosion and poor contact between two different metals, aluminum and copper, especially for hot rolling between thick aluminum layers (greater than 6mm) and high-strength and corrosion-resistant copper-aluminum alloys. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a high-strength corrosion-resistant copper-aluminum welding process, a copper-aluminum parallel groove wire clamp and production equipment.

[0005] In order to solve the above problems, the technical solution adopted by the present invention comprises the following steps:

[0006] Step 1: At room temperature, spray aluminum alloy particles onto the surface of a copper-nickel-silicon alloy workpiece by supersonic airflow to form an aluminum composite layer, wherein the particle size of the aluminum alloy particles is 10-14 μm;

[0007] Step 2: Welding the aluminum composite layer to the copper-nickel-silicon alloy workpiece by molecular diffusion welding process, with the welding temperature being 500° C.-600° C. and the welding pressure being 30-50 MPa;

[0008] Step 3: The aluminum composite layer is subjected to upsetting forging, the upsetting force is 100-400T, and the temperature during upsetting is maintained at 500°C-600°C.

[0009] The high-strength, corrosion-resistant copper-aluminum welding process is characterized in that: in step 1, the spraying thickness of the aluminum composite layer is 8-10 mm, and through the top forging in step 3, the thickness of the aluminum composite layer is compressed to 6-8 mm.

[0010] The high-strength, corrosion-resistant copper-aluminum welding process is characterized in that: the copper-nickel-silicon alloy workpiece contains copper: 90-95 mass%, nickel: 2-5 mass%, silicon: 1-2.5 mass%;

[0011] The aluminum alloy particles contain aluminum: balance, silicon: 0.30-0.4 mass %, copper: 0.15%-1.20 mass %, magnesium: 0.25-0.4 mass %, zinc: ≤0.10 mass %, manganese: ≤0.10 mass %, titanium: ≤0.10 mass %, chromium: ≤0.10 mass %, and iron: 0.000-0.350 mass %.

[0012] The high-strength, corrosion-resistant copper-aluminum welding process is characterized in that: the copper-nickel-silicon alloy workpiece contains copper: 93.5 mass%, nickel: 4.5 mass%, silicon: 2 mass%;

[0013] The aluminum alloy particles contain aluminum as the balance, 0.35 mass % silicon, 1 mass % copper, 0.3 mass % magnesium, 0.10 mass % zinc, 0.10 mass % manganese, 0.10 mass % titanium, 0.10 mass % chromium, and 0.250 mass % iron.

[0014] A copper-aluminum parallel groove wire clamp, comprising relatively arranged clamp arms and a bolt assembly connected to the middle of the clamp arms, one end of the clamp arm is provided with a copper wire clamp groove, and the other end is provided with an aluminum wire clamp groove, characterized in that: the surface of the aluminum wire clamp groove is provided with an aluminum composite layer, the clamp arm is made of a copper-nickel-silicon alloy material, the aluminum composite layer is made of an aluminum alloy material, and the aluminum composite layer and the clamp arm are produced by the high-strength and corrosion-resistant copper-aluminum welding process described in any one of the above items.

[0015] The copper-aluminum parallel groove wire clamp is characterized in that the copper wire clamp groove is a square structure, the aluminum wire clamp groove is an arc structure, and the aluminum composite layer of the aluminum wire clamp groove and the surface of the copper wire clamp groove are both provided with anti-slip serrations.

[0016] The copper-aluminum parallel groove wire clamp is characterized in that the bolt assembly includes a bolt and a flat washer, a spring washer and a nut arranged on the bolt in sequence, the rear end of the nut is integrally formed with an annular sealing portion, and a sealing ring is arranged in the annular sealing portion.

[0017] A production equipment, used for producing the copper-aluminum parallel groove wire clamp described in any of the above items, comprising a punching machine, a punching slide and a punching table located below the punching slide, characterized in that: the punching slide is provided with a top forging rod, the punching table is provided with a template, the template is provided with a clamp arm fixture, the top of the top forging rod is provided with an arc surface adapted to the aluminum wire clamp groove, the clamp arm fixture is provided with a groove adapted to the clamp arm, and the side walls of the groove block the two ends of the aluminum wire clamp groove.

[0018] The production equipment is characterized in that the upper end of the arc-shaped face of the top forging rod is provided with stamping serrations.

[0019] The production equipment is characterized in that the groove consists of an upper groove and a lower groove, and the upper groove is 1-3 mm wider than the lower groove.

[0020] The advantages of the high-strength corrosion-resistant copper-aluminum welding process, copper-aluminum parallel groove wire clamp and production equipment of the present invention are as follows: 1. It can realize welding of high-strength corrosion-resistant aluminum alloy material to the wire clamping groove of the high-strength corrosion-resistant clamp arm, and the interface bonding degree is high, and the aluminum layer is not easy to fall off; 2. It is not easy to electrochemically corrode and has high conductivity; 3. The overall high-strength and good corrosion resistance of the power parallel groove wire clamp is 5-10 times that of the traditional parallel groove wire clamp.

[0021] The present invention will be further described below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the structure of the copper-aluminum parallel groove wire clamp of the present invention;

[0023] Figure 2 1 is a front view and a side view of the clamp arm of the present invention;

[0024] Figure 3 It is a structural schematic diagram of a nut of the present invention;

[0025] Figure 4 It is a structural schematic diagram of the production equipment of the present invention;

[0026] Figure 5 is a longitudinal sectional view of the upset rod and the jig of the present invention;

[0027] Figure 6 is a transverse cross-sectional view of the jig of the present invention;

[0028] Figure 7 It is a structural schematic diagram of the top forging rod of the present invention. DETAILED DESCRIPTION Embodiment 1:

[0029] The high-strength corrosion-resistant copper-aluminum welding process of the present invention comprises the following steps:

[0030] Step 1: At room temperature, aluminum alloy particles are sprayed onto the surface of a copper-nickel-silicon alloy workpiece by supersonic airflow, so that the particles undergo strong plastic deformation and are deposited to form a coating, i.e., an aluminum composite layer, wherein the particle size of the aluminum alloy particles is 10-14 μm.

[0031] Step 2: Use molecular diffusion welding process (under certain temperature and pressure, the molecules between the contact surfaces of metal objects at high temperature are diffused to form a joint) to weld the aluminum composite layer and the copper-nickel-silicon alloy workpiece, the welding temperature is 500℃-600℃, ideally 550℃, and the pressure during welding is ideally 30-50MP, so as to achieve the best welding effect.

[0032] Step 3: The aluminum composite layer is subjected to upsetting, the upsetting force is 100-400T, preferably 300T, and the temperature during upsetting is maintained at 500°C-600°C, preferably 550°C. Through the upsetting process, the aluminum composite layer can be compressed to further improve the density and strength of the aluminum composite layer, while making the welding interface more bonded, thereby making the aluminum composite layer more difficult to fall off.

[0033] Preferably, in step 1, the spraying thickness of the aluminum composite layer is 8-10 mm, preferably 9 mm, and the thickness of the aluminum composite layer is compressed to 7 mm by upsetting in step 4, so as to achieve the best strength and interface bonding.

[0034] Preferably, the copper-nickel-silicon alloy workpiece contains copper: 90-95 mass%, nickel: 2-5 mass%, silicon: 1-2.5 mass%. The aluminum alloy particles contain aluminum: balance, silicon: 0.30-0.4 mass%, copper: 0.15%-1.20 mass%, magnesium: 0.25-0.4 mass%, zinc: ≤0.10 mass%, manganese: ≤0.10 mass%, titanium: ≤0.10 mass%, chromium: ≤0.10 mass%, iron: 0.000-0.350 mass%. The best: the copper-nickel-silicon alloy workpiece contains copper: 93.5 mass%, nickel: 4.5 mass%, silicon: 2 mass%; the aluminum alloy particles contain aluminum: balance, silicon: 0.35 mass%, copper: 1 mass%, magnesium: 0.3 mass%, zinc: 0.10 mass%, manganese: 0.10 mass%, titanium: 0.10 mass%, chromium: 0.10 mass%, iron: 0.250 mass%. The copper-nickel-silicon alloy and aluminum alloy using the above formula can be well applied to the production process of the present invention, so that the workpiece produced is not only high-strength and corrosion-resistant, but also has a high interface bonding degree, and the aluminum layer is not easy to fall off. Among them, the workpiece made of copper-nickel-silicon alloy has the following advantages:

[0035] 1. High strength and hardness, the hardness can reach 130-140HB;

[0036] 2. Good electrical conductivity and thermal conductivity. It inherits the excellent electrical conductivity of copper. At the same time, the addition of nickel and silicon improves the strength and corrosion resistance of the material. The electrical conductivity is 90-95% of pure copper.

[0037] Aluminum composite layer has the following advantages:

[0038] 1. It has high impact toughness, is insensitive to notches, and is suitable for heat treatment strengthening;

[0039] 2. It has excellent thermoplasticity and can be forged into forgings with complex structures at high speed;

[0040] 3. Excellent welding performance and corrosion resistance, no stress corrosion cracking. Embodiment 2:

[0041] like Figure 1-Figure 3 As shown, the copper-aluminum parallel groove wire clamp of the present invention comprises a clamp arm 1 arranged opposite to each other and a bolt assembly 2 connected to the middle of the clamp arm 1, one end of the clamp arm 1 is provided with a copper wire clamp groove 3, and the other end of the clamp arm 1 is provided with an aluminum wire clamp groove 4. The surface of the aluminum wire clamp groove 4 is provided with an aluminum composite layer 5, the clamp arm 1 is made of a copper-nickel-silicon alloy material, the aluminum composite layer 5 is made of an aluminum alloy material, and the aluminum composite layer 5 and the clamp arm 1 are produced by the high-strength, corrosion-resistant copper-aluminum welding process described in Example 1. The formula of the copper-nickel-silicon alloy material and the aluminum alloy material is also the same as that of Example 1.

[0042] Preferably, the copper wire clamping groove 3 is a square structure, and the aluminum wire clamping groove 4 is an arc-shaped structure. And the aluminum composite layer 5 of the aluminum wire clamping groove 4 and the surface of the copper wire clamping groove 3 are both provided with anti-skid serrations 6. When applied: the end of the copper wire needs to be processed into a square structure that is compatible with the copper wire clamping groove 3. Since the copper wire is relatively hard and has a smooth surface, the traditional circular clamping groove is used to connect the circular copper wire. When the wire is shaking, the two are prone to loosening due to relative rotation. However, this phenomenon can be eliminated by using a square mouth connection and combining the anti-skid serrations 6.

[0043] Preferably, the bolt assembly 2 includes a bolt 18 and a flat washer 19, a spring washer 20 and a nut 21 arranged on the bolt 18 in sequence, and an annular sealing portion 17 is integrally formed at the rear end of the nut 21, and a sealing ring 15 is arranged in the annular sealing portion 17. When the clamp arm 1 is fastened by the bolt assembly 2, the sealing ring 15 in the annular sealing portion 17 is sealed in the thread gap to prevent rainwater from penetrating and causing corrosion. Embodiment 3:

[0044] Reference Figure 4-Figure 7As shown, a production equipment of the present invention is used to produce the copper-aluminum parallel groove wire clamp described in Example 2, including a punch press 7, on which a punch press 7 is provided with a punching slide 8 and a punching table 9 located below the punching slide 8. The punching slide 8 is provided with a top forging rod 10, and the punching table 9 is provided with a template 11, and the template 11 is provided with a clamp arm fixture 12, and the top of the top forging rod 10 is provided with an arc surface 13 adapted to the aluminum wire clamp groove 4. The clamp arm fixture 12 is provided with a groove 14 adapted to the clamp arm 1, and the side wall of the groove 14 blocks (wraps) the two ends of the aluminum wire clamp groove 4, so that when the aluminum alloy particles are sprayed onto the surface of the aluminum wire clamp groove 4 by supersonic airflow, the particles will not splash outside, and the coating is easier to deposit, and during top forging, the aluminum material extruded at both ends can be blocked, so that the aluminum composite layer can be better compressed.

[0045] Preferably, the front end of the arc surface 13 of the upset rod 10 is provided with a stamping sawtooth 16. This allows the anti-slip sawtooth to be processed while the upset is being performed, thus omitting the subsequent lathe processing and achieving higher processing efficiency.

[0046] Preferably, the groove 14 is composed of an upper groove 141 and a lower groove 142, and the upper groove 141 is 1-3 mm wider than the lower groove 142. Since the aluminum layer formed by cold spraying may be uneven at both ends, by providing the widened upper groove 141, the aluminum composite layer formed by cold spraying is wider at both ends than the clamp arm 1, and can then be milled to ensure flatness.

[0047] As mentioned above, the present invention is not limited in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of the structures and technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A high-strength, corrosion-resistant copper-aluminum parallel groove wire clamp welding process, characterized in that: The copper-aluminum parallel groove wire clamp comprises clamp arms (1) arranged opposite to each other and a bolt assembly (2) connected to the middle of the clamp arm (1); one end of the clamp arm (1) is provided with a copper wire clamp groove (3) and the other end is provided with an aluminum wire clamp groove (4); the surface of the aluminum wire clamp groove (4) is provided with an aluminum composite layer (5); the clamp arm (1) is made of a copper-nickel-silicon alloy material, and the aluminum composite layer (5) is made of an aluminum alloy material; and the welding process is as follows: Step 1: At room temperature, aluminum alloy particles are sprayed onto the surface of the aluminum wire clamping groove (4) of the clamping arm (1) by supersonic airflow to form the aluminum composite layer (5), wherein the particle size of the aluminum alloy particles is 10-14 μm; Step 2: using a molecular diffusion welding process to weld the aluminum composite layer (5) and the clamp arm (1), the welding temperature being 500° C. to 600° C. and the welding pressure being 30 to 50 MPa; Step 3: performing upsetting forging on the aluminum composite layer (5), wherein the upsetting force is 100-400T and the temperature during upsetting is maintained at 500°C-600°C; In step 1, the spraying thickness of the aluminum composite layer (5) is 8-10 mm, and through the upsetting in step 3, the thickness of the aluminum composite layer (5) is compressed to 6-8 mm.

2. The high-strength, corrosion-resistant copper-aluminum parallel groove wire clamp welding process according to claim 1 is characterized in that: The copper-nickel-silicon alloy workpiece contains 90-95 mass % copper, 2-5 mass % nickel and 1-2.5 mass % silicon; The aluminum alloy particles contain aluminum: balance, silicon: 0.30-0.4 mass %, copper: 0.15%-1.20 mass %, magnesium: 0.25-0.4 mass %, zinc: ≤0.10 mass %, manganese: ≤0.10 mass %, titanium: ≤0.10 mass %, chromium: ≤0.10 mass %, and iron: 0.000-0.350 mass %.

3. The high-strength, corrosion-resistant copper-aluminum parallel groove wire clamp welding process according to claim 2 is characterized in that: The copper-nickel-silicon alloy workpiece contains 93.5 mass % copper, 4.5 mass % nickel and 2 mass % silicon; The aluminum alloy particles contain aluminum as the balance, 0.35 mass % silicon, 1 mass % copper, 0.3 mass % magnesium, 0.10 mass % zinc, 0.10 mass % manganese, 0.10 mass % titanium, 0.10 mass % chromium, and 0.250 mass % iron.

4. A production device for upsetting in the welding process of the high-strength, corrosion-resistant copper-aluminum parallel groove wire clamp according to any one of claims 1 to 3, comprising a punching machine (7), the punching machine (7) being provided with a punching slide (8) and a punching table (9) located below the punching slide (8), characterized in that: The punching slide (8) is provided with a forging rod (10), the punching table (9) is provided with a template (11), the template (11) is provided with a clamping arm fixture (12), the top of the forging rod (10) is provided with an arc surface (13) adapted to the aluminum wire clamping groove (4), the clamping arm fixture (12) is provided with a groove (14) adapted to the clamping arm (1), and the side wall of the groove (14) blocks the two ends of the aluminum wire clamping groove (4); the front end of the arc surface (13) of the forging rod (10) is provided with a punching sawtooth (16).

5. The production equipment according to claim 4, characterized in that: The groove (14) consists of an upper groove (141) and a lower groove (142), and the upper groove (141) is 1-3 mm wider than the lower groove (142).

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