Welding wire as well as preparation process and application of welding wire

Abstract

The welding wire comprises a welding wire main body, the welding wire main body comprises an outer core and an inner core wrapped by the outer core, the outer core is provided with a concave part, the concave direction of the concave part faces the inner core, and the concave part forms an opening shape in the outer wall of the outer core; the shortest distance between the inner wall face of the concave part and the inner core is smaller than the distance between the outer wall face of the outer core and the inner core. According to the welding wire and the preparation process and application of the welding wire, splashing loss of welding flux is reduced, and the process level is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of brazing media, and more specifically, to a welding wire, a preparation process of the welding wire and an application thereof. Background Art

[0002] Aluminum alloys have a small specific gravity, good electrical and thermal conductivity, and are widely used. It is difficult to braze between Al-Al and Al-Cu. To solve this problem, an active brazing flux composed of multiple fluorides is often filled in the core of the welding wire to make an aluminum alloy flux-cored welding wire to solve the brazing problem between Al-Al and Al-Cu.

[0003] Such as Figure 1 As shown, the welding wire medium 100 is a cylindrical filamentous welding wire medium 100 with a welding core 200 wrapped inside. The welding core 200 is an active brazing flux, and the one wrapping the welding core 200 is an aluminum alloy. When in use, the welding wire medium 100 is placed at the brazing position of two components, and the welding wire medium 100 is completely melted by heating so that the two components form a brazed joint.

[0004] Since the welding core 200 absorbs moisture during storage, and gas is mixed into the welding core 200 when the hollow core tube is filled with powder, when the welding wire medium 100 is heated, the moisture in the welding core 200 vaporizes, and the gas mixed into the welding core 200 expands, forming a local high pressure inside the welding wire medium 100. A bulging protrusion 101 is formed on the surface of the welding wire medium 100 and finally explodes. The thicker the wall thickness of the welding wire medium 100, the more serious the spatter generated by the explosion, resulting in a large loss of brazing flux, bringing troubles to production and affecting the brazing quality. Summary of the Invention

[0005] The purpose of the present invention is to overcome the above-mentioned deficiencies of the prior art, and provide a welding wire, a preparation process of the welding wire and an application thereof, to reduce the spatter loss of the brazing flux and improve the process level.

[0006] To achieve the above purpose, the present invention adopts the following technical scheme: A welding wire includes a welding wire main body, the welding wire main body includes an outer core and an inner core wrapped by the outer core. The outer core is provided with a concave portion, the concave portion is recessed towards the inner core, the concave portion forms an open shape on the outer wall of the outer core, and the shortest distance between the inner wall surface of the concave portion and the inner core is less than the distance between the outer wall surface of the outer core and the inner core.

[0007] The present invention is further configured such that the welding wire main body is a long strip structure, the outer core and the inner core both extend along the length direction of the welding wire main body, and the concave portions are distributed at intervals along the length direction of the outer core.

[0008] The present invention is further configured such that an arc portion is provided at the end of the concave portion close to the inner core.

[0009] The present invention also adopts the following technical scheme: A preparation process includes the following steps;

[0010] S Welding wire forming:

[0011] The wire electrode body is formed by powder filling through a hollow tube or by powder filling and extrusion of an ingot.

[0012] S Use the preparation tooling for reprocessing:

[0013] ① The preparation tooling includes a first roller die and a second roller die, and the wire electrode body passes through between the first roller die and the second roller die;

[0014] ② Needles are circumferentially installed on the first roller die. The wire electrode body is axially pulled, and the needles are squeezed into the outer core to form recesses.

[0015] The present invention is further configured such that the axial direction of the first roller die is parallel to the axial direction of the second roller die, and the axial direction of the wire electrode body is arranged tangentially along the first roller die.

[0016] The present invention is further configured such that the first roller die is provided with a first groove body, the second roller die is provided with a second groove body, the wire electrode body passes through the first groove body and the second groove body, and the outer wall of the wire electrode body abuts against the wall surfaces of the first groove body and the second groove body.

[0017] The present invention is further configured such that a plurality of needles are evenly distributed circumferentially along the first roller die. The length direction of the needles is arranged radially along the first roller die. A pointed portion is provided on the side of the needles away from the center of the first roller die, and the pointed portion can be squeezed into the outer core to form a recess.

[0018] The present invention is further configured such that a fillet is provided on the side of the pointed portion away from the center of the first roller die.

[0019] The present invention is further configured such that both the first roller die and the second roller die can rotate along their own axes.

[0020] The present invention also adopts the following technical solution: An application of a wire electrode. The wire electrode body welds welding component one and welding component two to each other. Welding component one is provided with a socket hole. The bottom of welding component two is inserted into the socket hole. The bottom of the outer core abuts against the upper end surface of welding component one, and the side portion of the outer core abuts against the outer wall of welding component two. The opening formed by the recess faces the outer wall of welding component two.

[0021] In summary, the present invention has the following beneficial effects:

[0022] By providing the recess, the pressure for the water vapor inside the inner core to vaporize and burst the outer wall of the outer core becomes lower, and it is easy to release the internal water vapor. At the same time, the splashing of the inner core generated during the release is less, reducing the loss of the inner core. Meanwhile, the position where the water vapor inside the inner core vaporizes and bursts is controllable, facilitating the adjustment of the process to reduce its impact on production. Description of the Drawings

[0023] Figure 1 It is a schematic diagram of the background art;

[0024] Figure 2 Cross-sectional view of Example 1;

[0025] Figure 3 Schematic cross-sectional view of Example 2;

[0026] Figure 4 is Figure 3 Enlarged view of part A in

[0027] Figure 5 is Figure 3 Partial cross-sectional view in the M-M direction of

[0028] Figure 6 Schematic view of Example 3.

[0029] Reference numerals: First roller die 1, First trough 11, Second roller die 2, Second trough 21, Installation groove 22, Needle body 3, Tip 31, Fillet 311, Welding wire body 4, Outer core 41, Concave portion 411, Arc portion 4111, Inner core 42, Welding component 1 5, Socket 51, Welding component 2 6, Welding wire medium 100, Protrusion 101, Welding core 200. Detailed implementation manners

[0030] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0031] Example 1:

[0032] As Figure 2 shown, this example discloses a welding wire. The welding wire includes a welding wire body 4. The welding wire body is a long strip structure. Specifically, the welding wire body 4 is a cylindrical filamentous structure. Figure 2 is a cross-sectional view of the welding wire. The welding wire body 4 includes an outer core 41 and an inner core 42 wrapped by the outer core 41. Both the outer core 41 and the inner core 42 extend along the length direction of the welding wire body 4. The inner core 42 is a brazing powder medium, the outer core 41 is an aluminum alloy, the melting point of the outer core 41 is lower than the melting point of the component to be brazed, and the melting point of the inner core 42 is lower than the melting point of the outer core 41.

[0033] The outer core 41 is provided with a concave portion 411. The concave direction of the concave portion 411 faces the inner core 42. The concave portion 411 forms an opening on the outer wall of the outer core 41. The shortest distance between the inner wall surface of the concave portion 411 and the inner core 42 is less than the distance between the outer wall surface of the outer core 41 and the inner core 42. The concave portion 411 is conical, and the concave portions 411 are distributed at intervals along the length direction of the outer core 41.

[0034] When heated, the moisture inside the inner core 42 vaporizes first. The shortest distance between the inner wall surface of the concave portion 411 and the inner core 42 is prone to form a bursting point. The water vapor bursts out from this place and breaks through the outer wall of the outer core 41, and at the same time, part of the inner core 42 also flows out. By setting the concave portion 411, the pressure for the moisture inside the inner core 42 to vaporize and burst through the outer wall of the outer core 41 becomes lower, which is easy to release the internal water vapor, and there is less splashing of the inner core 42 during the release, reducing the loss of the inner core 42. At the same time, the position where the moisture inside the inner core 42 vaporizes and bursts is controllable, facilitating the adjustment of the process to reduce its impact on production.

[0035] An arc portion 4111 is provided at the end of the concave portion 411 close to the inner core 42 to prevent the concave portion 411 from communicating with the inner core 42 during the processing and forming of the concave portion 411, resulting in the exposure of the inner core 42 and deterioration due to moisture absorption.

[0036] Embodiment Two:

[0037] As Figures 3 - 5 shown, this embodiment discloses a preparation process for a welding wire, which is used to process the welding wire in Embodiment One, and specifically includes the following steps;

[0038] S1 Welding wire forming:

[0039] The welding wire body 4 is formed by filling powder through a hollow tube, and then drawn and reduced in diameter to the required diameter to form a cylindrical filamentous structure. The overall mass reaches 3 Kg - 5 Kg, and the welding wire body 4 can be continuously brazed during use;

[0040] S2 Re - process the welding wire body 4 using a preparation tooling:

[0041] ① The preparation tooling includes a first roller die 1 and a second roller die 2. Both the first roller die 1 and the second roller die 2 are disc - shaped structures. Rotating shafts are installed at the centers of the first roller die 1 and the second roller die 2 respectively, and both the first roller die 1 and the second roller die 2 can rotate along their own axes. The axis of the first roller die 1 is parallel to the axis of the second roller die 2.

[0042] The welding wire body 4 passes through between the first roller die 1 and the second roller die 2. Specifically, the axis of the welding wire body 4 is arranged tangentially along the first roller die 1. The first roller die 1 is provided with a first groove 11, and the first groove 11 is recessed radially inward along the outer wall of the first roller die 1. The first groove 11 is arranged circumferentially along the first roller die 1 to form a ring. The second roller die 2 is provided with a second groove 21, and the second groove 21 is recessed radially inward along the outer wall of the second roller die 2. The second groove 21 is arranged circumferentially along the second roller die 2 to form a ring. The welding wire body 4 passes through the first groove 11 and the second groove 21, and the outer wall of the welding wire body 4 is in contact with the wall surfaces of the first groove 11 and the second groove 21. As Figure 3As shown, the welding wire body 4 is pulled to the right along the arrow direction, and the frictional force between the welding wire body 4 and the wall surfaces of the first groove body 11 and the second groove body 21 drives the first roller die 1 and the second roller die 2 to rotate.

[0043] ② Needles 3 are circumferentially installed on the first roller die 1. Specifically, the first roller die 1 is provided with installation grooves 22. The installation grooves 22 penetrate the outer wall of the first roller die 1. The length direction of the installation grooves 22 is arranged along the radial direction of the first roller die 1, and a plurality of installation grooves 22 are provided along the circumferential direction of the first roller die 1. As Figure 4 shown, needles 3 are installed in the installation grooves 22. The needles 3 are inserted and fixed in the installation grooves 22. The length direction of the needles 3 is arranged along the radial direction of the first roller die 1. A tip 31 is provided on the side of the needle 3 away from the center of the first roller die 1, and the tip 31 extends out of the first roller die 1.

[0044] As Figure 3 shown, the welding wire body 4 is pulled to the right along the axial direction. The welding wire body 4 drives the first roller die 1 and the second roller die 2 to rotate, and the tip 31 squeezes into the outer core 41 to form a recess 411. As the welding wire body 4 is continuously pulled, a plurality of tips 31 form recesses 411 distributed at intervals on the outer wall of the outer core 41.

[0045] By providing recesses 411 distributed at intervals on the outer wall of the outer core 41, the recesses 411 serve as breakthrough points for the vaporization and explosion of the moisture absorbed by the inner core 42, so that a plurality of fixed-position explosion ports are formed at intervals in the length direction of the outer core 41, which is convenient for unified control of these explosion ports. Since the shortest distance between the inner wall surface of the recess 411 and the inner core 42 is less than the distance between the outer wall surface of the outer core 41 and the inner core 42, when the air pressure in the outer core 41 is slightly stronger, the air flow is likely to break through the outer core 41, reducing the splashing phenomenon of the inner core 42 and reducing the loss of the inner core 42 (i.e., the loss of the brazing medium), thereby improving the process level.

[0046] A fillet 311 is provided on the side of the tip 31 away from the center of the first roller die 1. By providing the fillet 311, it is possible to prevent the tip 31 from completely piercing the outer core 41 during the process of squeezing into the outer core 41 to form a recess 411, resulting in the exposure of the inner core 42.

[0047] Example three:

[0048] As Figure 6As shown in the figure, this embodiment discloses the application of the welding wire described in Embodiment 1. The welding wire body 4 welds the first welding component 5 and the second welding component 6 to each other. The first welding component 5 is provided with an insertion hole 51, the bottom of the second welding component 6 is inserted into the insertion hole 51, the bottom of the outer core 41 abuts against the upper end surface of the first welding component 5, and the side of the outer core 41 abuts against the outer wall of the second welding component 6. The opening formed by the concave portion 411 faces the welding point on the outer wall of the second welding component 6. After heating, the inner core 42 melts first, the moisture in the inner core 42 vaporizes and breaks through the wall surface of the concave portion 411, and the inner core 42 sprays out from the concave portion 411 and sprays towards the second welding component 6. The position where the inner core 42 sprays is at the welding point of the second welding component 6, without causing waste of the welding flux. At the same time, the sprayed inner core 42 is blocked by the second welding component 6, reducing the spatter phenomenon, improving production safety and reducing production costs. Part of the sprayed inner core 42 flows into the connection part between the insertion hole 51 and the second welding component 6, making the connection between the first welding component 5 and the second welding component 6 more firm after brazing and improving the reliability of the process.

[0049] As the heating continues, the welding wire body 4 completely melts, and after cooling, the welding wire body 4 welds the first welding component 5 and the second welding component 6 to each other.

[0050] The above are only the preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions within the idea of the present invention belong to the protection scope of the present invention. It should be pointed out that for those of ordinary skill in the art, several improvements and refinements made without departing from the principle of the present invention should also be regarded as within the protection scope of the present invention.

Claims

1. A welding wire, characterized in that, It includes a welding wire body (4), the welding wire body (4) includes an outer core (41) and an inner core (42) wrapped by the outer core (41). The outer core (41) is provided with a recess (411), the recess (411) is recessed towards the inner core (42), the recess (411) forms an opening on the outer wall of the outer core (41), and the shortest distance between the inner wall surface of the recess (411) and the inner core (42) is less than the distance between the outer wall surface of the outer core (41) and the inner core (42).

2. A welding wire according to claim 1, characterized in that, The welding wire body (4) is of a long strip structure, the outer core (41) and the inner core (42) both extend along the length direction of the welding wire body (4), and the recesses (411) are distributed at intervals along the length direction of the outer core (41).

3. A welding wire according to claim 1, characterized in that, An arc portion (4111) is provided at the end of the recess (411) close to the inner core (42).

4. A preparation process of a welding wire as described in claim 2, characterized in that, It includes the following steps; S1 Welding wire forming: The welding wire body (4) is formed by filling powder into a hollow tube and then drawn and reduced in diameter to the required diameter; S2 Re-processing using a preparation tooling: ① The preparation tooling includes a first roller die (1) and a second roller die (2), and the welding wire body (4) passes between the first roller die (1) and the second roller die (2); ② Needle bodies (3) are circumferentially installed on the first roller die (1), the welding wire body (4) is axially pulled, and the needle bodies (3) are squeezed into the outer core (41) to form the recesses (411).

5. The preparation process of a welding wire according to claim 4, characterized in that, The axis of the first roller die (1) is parallel to the axis of the second roller die (2), and the axis of the welding wire body (4) is arranged tangentially along the first roller die (1).

6. The preparation process of a welding wire according to claim 4, characterized in that, The first roller die (1) is provided with a first groove body (11), the second roller die (2) is provided with a second groove body (21), the welding wire body (4) passes through the first groove body (11) and the second groove body (21), and the outer wall of the welding wire body (4) abuts against the wall surfaces of the first groove body (11) and the second groove body (21).

7. The preparation process of a welding wire according to claim 4, characterized in that, A plurality of needle bodies (3) are evenly distributed along the circumference of the first roller die (1), the length direction of the needle bodies (3) is arranged along the radial direction of the first roller die (1), a pointed portion (31) is provided on the side of the needle bodies (3) away from the center of the first roller die (1), and the pointed portion (31) can be squeezed into the outer core (41) to form the recesses (411).

8. The preparation process of a welding wire according to claim 7, characterized in that, A fillet (311) is provided on the side of the pointed portion (31) away from the center of the first roller die (1).

9. The preparation process of a welding wire according to claim 4, characterized in that, Both the first roller die (1) and the second roller die (2) can rotate along their own axes.

10. Use of a welding wire as claimed in claim 1, characterized in that, The welding wire body (4) welds the welding component one (5) and the welding component two (6) to each other. The welding component one (5) is provided with a jack (51), the bottom of the welding component two (6) is inserted into the jack (51), the bottom of the outer core (41) abuts against the upper end surface of the welding component one (5), the side portion of the outer core (41) abuts against the outer wall of the welding component two (6), and the opening formed by the recess (411) faces the welding point on the outer wall of the welding component two (6).

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