Electron track control device and vacuum electron beam seal welding device

Abstract

The utility model discloses an electron track control device and a vacuum electron beam seal welding device, the electron track control device comprises N pairs of metal plates which are opposite pairwise, the middle point of the relative distance of each pair of metal plates is coaxial with the center line of an electron beam, and each pair of metal plates is provided with a uniform electric field; when an upper-layer welding seam is welded, applying a uniform electric field to counteract an upward deflection force generated by an electron beam under the influence of the magnetic field; when a lower-layer welding seam is welded, a downward deflection force generated by an electron beam under the influence of a magnetic field is counteracted by applying a reverse uniform electric field; according to the vacuum electron beam seal welding device, the welding precision of electron beams can be effectively improved, the seal welding quality of a titanium steel composite blank is guaranteed, and a continuous, uniform and large-fusion-depth seal welding joint is formed; and the problems of electron beam drifting, welding seam deflection, welding missing, low fusion depth and the like easily occurring in the current vacuum electron beam welding technology for the magnetic titanium steel composite blank are effectively solved.

Description

Technical Field

[0001] The utility model relates to the technical field of metal material processing, in particular to a vacuum electron beam welding device and a method for sealing and welding titanium steel composite billets. Background Art

[0002] Titanium-steel composite plates have both the excellent corrosion resistance of the titanium composite layer and the strength and plasticity of the base structural steel. Compared with titanium plates, their economic costs are greatly reduced. They are ideal materials for manufacturing equipment in corrosion-resistant environments. They have been promoted and applied in the fields of petrochemicals, salt making, electricity, seawater desalination, marine engineering, etc., and have great application potential.

[0003] In recent years, the method of vacuum electron beam sealing welding titanium steel composite billet + hot rolling has been widely used in the industrialized production of titanium steel composite plates at home and abroad, and can stably produce large-width titanium steel composite plate products. Among them, the preparation of composite billets used to produce titanium steel composite plates, as a basic link in the production of composite plates, has received extensive attention from many scholars. At present, the commonly used billet assembly method is generally to place the titanium plate in a hollow composite billet composed of two carbon steel plates and a steel frame of a certain thickness, and then use vacuum electron beam welding technology to seal and weld the billet.

[0004] Vacuum electron beam welding technology can be used to weld large penetration weld joints under high vacuum conditions. It has the characteristics of high energy density, small heat-affected zone, and strong penetration, and can achieve vacuum sealing of large composite billets. However, since electron beam welding technology uses high-speed electrons to bombard the target material to achieve melting and welding, it is greatly affected by the magnetic field. Although it is strictly controlled during the processing of titanium-steel composite billets, magnetic pollution is inevitably formed during the processing and lifting of titanium composite materials and steel substrates. In particular, after the titanium composite materials and steel substrates are assembled, the complex structure and huge differences in material properties make the magnetic field distribution more uneven, with one side concentrated at the corners of the composite billet, and the intensity is between 10 and 100 GS. In this case, when electron beam sealing is performed, the electron beam will be deflected toward the corners of the composite billet, resulting in sealing failure problems such as electron beam deflection, weld drift, leaking welds, and low penetration depth. The electron beam deflection effect is shown in the attached figure. Figure 1 In order to achieve the requirement of effective sealing welding penetration of more than 30mm, it is often necessary to re-heat treat to reduce the magnetic field strength to below 10GS for normal electron beam welding, which not only seriously reduces production efficiency, but also greatly increases production costs, and even causes rolling composite failure. Utility Model Content

[0005] In view of this, the utility model provides a vacuum electron beam sealing welding device for magnetic titanium steel composite billets, which solves the problems of electron beam drift, weld deflection, welding leakage and low penetration depth that are prone to occur in the current vacuum electron beam welding technology for magnetic titanium steel composite billets.

[0006] In addition, the utility model also provides an electron trajectory control device to support the vacuum electron beam sealing device.

[0007] In a first aspect, the electronic trajectory control device comprises:

[0008] N pairs of metal plates are opposite to each other, the midpoint of the relative spacing between each pair of metal plates is coaxial with the center line of the electron beam, and each pair of metal plates is configured with a uniform electric field;

[0009] When welding the upper weld, a uniform electric field is applied to offset the upward deflection force of the electron beam caused by the influence of the magnetic field; when welding the lower weld, a reverse uniform electric field is applied to offset the downward deflection force of the electron beam caused by the influence of the magnetic field.

[0010] In the present disclosure and possible embodiments, the N pairs of metal plates are three pairs of metal plates;

[0011] Measured from the direction of entry of the electron beam, the lengths of the first pair of metal plates, the second pair of metal plates and the third pair of metal plates are b1 = electron beam focal length / 3, b2 = electron beam focal length / 4, b3 = electron beam focal length / 5, and the relative spacings are d1 = 20mm~30mm, d2 = 15mm~20mm, d3 = 10mm~15mm.

[0012] In the present disclosure and possible embodiments, the width of the metal plate is 80 mm to 100 mm.

[0013] In the present disclosure and possible embodiments, the spacing between two adjacent pairs of metal plates is configured to be 10 mm.

[0014] In the present disclosure and possible embodiments, the electric field voltage U between the two metal plates is 640-960V.

[0015] In the present disclosure and possible embodiments, the metal plates are connected to a power-on unit, and the power-on unit is used to form a uniform electric field between two opposing metal plates.

[0016] In the present disclosure and possible embodiments, N pairs of metal plates facing each other are fixed on an insulating frame, a baffle is disposed on one side of the insulating frame, the baffle has a through hole, and the electron beam passes through the through hole.

[0017] In a second aspect, the vacuum electron beam sealing device comprises:

[0018] The electronic trajectory control device described in the first aspect.

[0019] Beneficial effects of the utility model:

[0020] The vacuum electron beam sealing welding device of the present application is configured with an electronic trajectory control device in front of the electron beam welding gun. When welding the upper weld, a uniform electric field is applied to offset the upward deflection force of the electron beam caused by the influence of the magnetic field; when welding the lower weld, a uniform reverse electric field is applied to offset the downward deflection force of the electron beam caused by the influence of the magnetic field. Therefore, under the condition of a magnetic field strength of 10 to 100GS, the welding accuracy of the electron beam can be improved, the sealing welding quality of the titanium-steel composite billet can be guaranteed, and a continuous, uniform, and deep-penetration sealing joint can be formed; and the problems of electron beam drift, weld deflection, welding leaks, and low penetration that are prone to occur in the current vacuum electron beam welding technology for magnetic titanium-steel composite billets can be effectively solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0022] Figure 1 It is a schematic diagram of sealing failure when the electron beam seals the magnetically contaminated titanium steel composite billet as described in the background art;

[0023] Figure 2 is a schematic structural diagram of an electronic trajectory control device according to an embodiment of the present disclosure;

[0024] Figure 3 It is a state diagram of electron beam sealing using an electron trajectory control device according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0025] The present disclosure is described below based on embodiments, but it is worth noting that the present disclosure is not limited to these embodiments. In the detailed description of the present disclosure below, some specific details are described in detail. However, for the parts that are not described in detail, those skilled in the art can also fully understand the present disclosure.

[0026] In addition, those skilled in the art should understand that the drawings are provided only to illustrate the purpose, features and advantages of the present disclosure, and the drawings are not actually drawn to scale. At the same time, unless the context clearly requires, the words "include", "comprise" and the like in the entire specification and claims should be interpreted as inclusive rather than exclusive or exhaustive; that is, "including but not limited to" meaning.

[0027] Figure 2 is a schematic diagram of the structure of the electronic trajectory control device of the embodiment of the present disclosure; Figure 2In the invention, the electron trajectory control device comprises three pairs of metal plates which are opposite to each other, the center of the relative spacing of each pair of metal plates is coaxial with the axis of the electron beam, the width of each metal plate is 80 mm to 100 mm, and the spacing between two adjacent pairs of metal plates is 10 mm; from the direction of electron beam entry, they are respectively the first pair of metal plates, the second pair of metal plates and the third pair of metal plates, wherein the lengths of the first pair of metal plates, the second pair of metal plates and the third pair of metal plates are respectively b1=electron beam focal length / 3, b2=electron beam focal length / 4, and b3=electron beam focal length / 5; the relative spacings of the first pair of metal plates, the second pair of metal plates and the third pair of metal plates are respectively d1=20 mm to 30 mm, d2=15 mm to 20 mm, and d3=10 mm to 15 mm.

[0028] The width a of the metal plate designed in the present disclosure is 80 to 100 mm. If the plate width is too small, it is difficult to form an effective uniform electric field, and the electron beam trajectory cannot be effectively regulated. If the plate width is too large, it increases the difficulty of loading stable charges, resulting in a decrease in the uniformity of the electric field.

[0029] The lengths of the three pairs of metal plates designed in the present disclosure are b1=electron beam focal length / 3, b2=electron beam focal length / 4, b3=electron beam focal length / 5, and the spacings between the three pairs of metal plates that are completely opposite to each other are d1=20-30mm, d2=15-20mm, and d3=10-15mm. The purpose is to correct the electrons emitted by the welding gun step by step so that they will not be deflected when they reach the sealing joint. Because the closer to the surface of the composite blank, the higher the intensity of the magnetic field, in order to avoid the effect of magnetic fields of different intensities on electrons, the utility model adopts different metal plate lengths and relative spacing settings. If the length of the metal plate is too small, the effect time of the electric field formed by it on the electrons is too short, and it cannot offset the effect of the magnetic field on the electrons; if the length of the metal plate is too long, because the magnetic field intensity is stronger the closer to the composite blank, the metal plate is too long, resulting in the inability of the latter half to offset the effect of the magnetic field on the electrons. If the relative spacing is too large, the intensity of the electric field generated by it on the electrons will be too small to control the deflection of the electrons; if the relative spacing is too small, it will be easily affected by welding spatter and reduce the ability to control electrons.

[0030] Each metal plate of the electronic trajectory control device is connected to a power-on unit, which enables the six metal plates to carry equal amounts of positive and negative charges, thereby forming an equal-intensity electric field between the metal plates facing each other.

[0031] The electric field voltage U between the two metal plates of the disclosed design is 640~960V. If U between the two metal plates is too small, the electric field strength formed is too small, and the electron beam trajectory cannot be effectively regulated. If U between the two metal plates is too large, discharge problems are likely to occur during the welding process.

[0032] It should be noted that Figure 2 Three pairs of metal plates are shown. Of course, according to the on-site conditions, the number of metal plates facing each other can be two pairs or more pairs. In terms of effect, the more pairs, the better the effect. However, it is still necessary to comprehensively consider the cost and on-site implementation conditions before making a decision. If other numbers of metal plates are used, the parameters such as the width, length, relative spacing and adjacent spacing of the metal plates can be obtained through a limited number of experimental screenings based on the technical concept of the method of the utility model, and the present disclosure does not limit this.

[0033] exist Figure 2 In the embodiment, three pairs of metal plates facing each other are fixed on an insulating frame 2. A baffle 1 is disposed on one side of the insulating frame 2. The baffle 1 has a through hole through which the electron beam passes.

[0034] The disclosed embodiment also provides a vacuum electron beam sealing device using the electron trajectory control device.

[0035] Specifically, the vacuum electron beam sealing welding device of the embodiment of the present disclosure is used to perform vacuum electron beam sealing welding on the magnetically contaminated titanium-steel composite billet, which specifically includes the following steps:

[0036] 1. Send the magnetically contaminated titanium steel composite billet into the vacuum chamber:

[0037] The magnetically contaminated titanium-steel composite billet is formed by placing two titanium plates in the core of a composite billet which is formed by stacking a carbon steel substrate, a steel frame and a carbon steel substrate in sequence, and there are two horizontal joints on each side of the billet which need to be vacuum electron beam sealed.

[0038] The length of the composite billet is 3 to 4 m, and the width is 1.5 to 3 m.

[0039] 2. Install an electronic trajectory control device on the vacuum electron beam welding gun:

[0040] like Figure 3 As shown, the electron beam center line of the electron beam welding gun 3 is made coaxial with the midpoint of the relative spacing between the three pairs of metal plates facing each other in parallel with the weld direction; and the distance between the third pair of metal plates and the workpiece to be welded is adjusted to be equal to the distance between the first pair of metal plates and the baffle 1, and the distance between the third pair of metal plates and the surface of the sealing joint is d0 = 10mm ~ 15mm.

[0041] In this embodiment, the distance d0 between the third pair of metal plates and the surface of the sealing joint is 10-15 mm, the purpose of which is to effectively control the movement direction of electrons on the surface of the sealing joint and to avoid the influence of welding spatter on the electric field generating device. If the distance is too small, welding spatter is easy to adhere to the metal plate, affecting the intensity and uniformity of the electric field; if the distance is too large, it is impossible to effectively control the movement direction of electrons on the surface of the sealing joint.

[0042] 3. Extract vacuum to make the vacuum degree of the vacuum chamber reach below 4.5×10-2Pa;

[0043] 4. Activate the electronic trajectory control device:

[0044] By using the power-on unit, the six metal plates are given equal positive and negative charges, forming an equal-strength electric field between the two opposing metal plates. The upper and lower metal plates are both charged. Specifically, when sealing the upper weld, the upper plate is negatively charged and the lower plate is positively charged; when sealing the lower weld, the upper plate is positively charged and the lower plate is negatively charged; the U between each pair of metal plates is 640~960V.

[0045] 5. Perform vacuum electron beam packaging welding:

[0046] The arc starting position and arc ending position of vacuum electron beam welding are 100 to 200 mm away from the two end points. The welding route is to start the arc from the arc starting position, weld to the end that is closer, weld to the end point, then return to the other end point, and then return to the arc ending position.

[0047] Since the magnetic field strength of the titanium-steel composite billet contaminated by magnetism is relatively high at the corners, if the arc is started and closed directly at the two end points, it is easily affected by the strong magnetic field, the electron beam deflects to a large extent, and it is easy to drift and leave the workpiece surface. The disclosed method preheats the end by welding heat input at a special distance to reduce the magnetic field strength, and under the action of the electronic trajectory control device, the electron trajectory can be effectively regulated.

[0048] When the titanium steel composite billet is sealed, the short side of the lower layer is sealed first, then the short side opposite to it is sealed, and then the long side adjacent to it is sealed. The upper layer is sealed in the above order. Since the magnetic field strength at the corners of the titanium steel composite billet is relatively large, the utility model adopts the method of welding the short side first and then the long side, so that the short side can be connected first during the welding process, further reducing the magnetic field strength at the sides and corners, and further improving the accuracy of the electron beam.

[0049] Among them, a negative defocus welding process is used during vacuum electron beam welding, and the defocus amount is -3 to -5 mm. On the one hand, the use of a negative defocus welding process helps to obtain a sealing joint with a large penetration depth and improve the reliability of the joint; on the other hand, it can further shorten the distance between the electron beam welding gun 3 and the workpiece, reduce the degree of deflection of the electron beam affected by the magnetic field, and facilitate the regulation and restraint of the electron beam trajectory by the additional electric field.

[0050] When welding the upper weld, a uniform electric field is applied to offset the upward deflection force of the electron beam caused by the influence of the magnetic field; when welding the lower weld, a uniform reverse electric field is applied to offset the upward deflection force of the electron beam caused by the influence of the magnetic field.

[0051] According to the above method steps, vacuum electron beam sealing welding is performed on the magnetic titanium steel composite billets of the following Examples 1-4 and the comparative example. The sealing welding process parameters are as shown in Table 1 and Table 2:

[0052] Table 1 Sealing and welding information of magnetic titanium steel composite billet

[0053]

[0054]

[0055] Table 2 Electric field information of three pairs of metal plates

[0056]

[0057] The sealing effects of the above-mentioned embodiments 1-4 and the comparative example are shown in Table 3:

[0058] Table 3 Sealing effect of Examples 1-4 and Comparative Examples

[0059] serial number Composite billet sealing results Example 1 During normal welding, the effective penetration depth is more than 35mm. Example 2 During normal welding, the effective penetration depth is more than 35mm. Example 3 During normal welding, the effective penetration depth is more than 36mm. Example 4 During normal welding, the effective penetration depth is more than 35mm. Comparative Example 1 There is a 320mm length of leakage welding at the corner, while the rest of the surface is fused, and the effective melting depth is only 5 to 10mm. Comparative Example 2 The electron beam is severely deflected and welding is impossible.

[0060] It can be seen from Table 3 that the vacuum electron beam sealing welding device equipped with an electronic trajectory control device in the embodiment of the present disclosure has a good sealing welding effect on the magnetic titanium-steel composite billet, and effectively solves the problems such as electron beam drift, weld deflection, weld leakage and low penetration depth that are prone to occur during the sealing welding of the magnetic titanium-steel composite billet.

[0061] The above-described embodiments are only embodiments of the present disclosure, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the present disclosure. It should be noted that, for a person of ordinary skill in the art, without departing from the concept of the present disclosure, several variations, equivalent substitutions, improvements, etc. may be made, all of which fall within the scope of protection of the present disclosure. Therefore, the scope of protection of the present disclosure shall be subject to the attached claims.

Claims

1. An electronic trajectory control device, characterized in that: include: N pairs of metal plates are opposite to each other, the midpoint of the relative spacing between each pair of metal plates is coaxial with the center line of the electron beam, and each pair of metal plates is configured with a uniform electric field; When welding the upper weld, a uniform electric field is applied to offset the upward deflection force of the electron beam caused by the magnetic field; when welding the lower weld, a reverse uniform electric field is applied to offset the downward deflection force of the electron beam caused by the magnetic field. The N pairs of metal plates are three pairs of metal plates; Measured from the direction of entry of the electron beam, the lengths of the first pair of metal plates, the second pair of metal plates and the third pair of metal plates are b1 = electron beam focal length / 3, b2 = electron beam focal length / 4, b3 = electron beam focal length / 5, and the relative spacings are d1 = 20mm~30mm, d2 = 15mm~20mm, d3 = 10mm~15mm.

2. The electronic trajectory control device according to claim 1, characterized in that: The width of the metal plate is 80 mm to 100 mm.

3. The electronic trajectory control device according to claim 2, characterized in that: The spacing between two adjacent pairs of metal plates is configured to be 10 mm.

4. The electronic trajectory control device according to claim 3, characterized in that: The electric field voltage U between each pair of metal plates is 640~960V.

5. The electronic trajectory control device according to any one of claims 1 to 4, characterized in that: The metal plates are connected to a power-on unit, and the power-on unit is used to form a uniform electric field between two opposing metal plates.

6. The electronic trajectory control device according to claim 5, characterized in that: N pairs of metal plates facing each other are fixed on an insulating frame (2); a baffle (1) is arranged on one side of the insulating frame (2); the baffle (1) has a through hole, and the electron beam passes through the through hole.

7. A vacuum electron beam sealing device, characterized in that: include: The electronic trajectory control device according to any one of claims 1 to 6.

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