Welding method for nickel-based alloy composite plate

Abstract

The invention discloses a welding method for a nickel-based alloy composite board. The nickel-based alloy composite board comprises a base material layer and a nickel-based alloy composite material layer, and a transition layer is arranged at the bonding interface of the base material layer and the nickel-based alloy composite material layer. Wherein a trapezoidal groove is machined in the position, corresponding to the base material layer, of the welding section of the nickel-based alloy composite board; a U-shaped groove is machined in the position, corresponding to the transition layer, of the welding section of the nickel base alloy; a groove is not machined in the position, corresponding to the nickel-based alloy composite material layer, of the welding section of the nickel-based alloy composite plate; a nickel-based alloy welding wire matched with the nickel-based alloy composite material layer is used, single argon tungsten-arc welding is adopted for welding the nickel-based alloy composite material layer, and a composite material layer welding seam is formed; a nickel-based alloy welding wire matched with the nickel-based alloy composite material layer is used, the transition layer is welded through single argon tungsten-arc welding, and a transition layer welding seam is formed; and the base material layer is welded to form a base material layer welding seam, and double-tungsten-electrode argon arc welding is adopted for welding the first welding bead of the base material layer.

Description

Technical Field

[0001] The invention relates to a welding method, in particular to a welding method for a composite plate. Background Art

[0002] Since nickel-based alloy composite plates contain two metals with two components and completely different properties, multi-layer and multi-pass welding is required when connecting them. The welds are divided into composite layers, transition layers, and base welds, and welded separately. In the final closed welding process of some composite plate components in industry, such as small pressure vessels and oil and gas pipelines, due to limited operating space, their connection requires single-sided welding starting from the composite layer. Since the content of alloying elements such as Cr, Ni, and Mn in nickel-based alloys is very high, the carbon steel welds adjacent to the nickel-based alloys are very easy to be modified due to the melting of a large amount of alloying elements, and the toughness is greatly deteriorated. Therefore, it is difficult to control the toughness of the welds of nickel-based alloy composite plates under this welding sequence. In response to this problem, the current main solution in the industry is to use nickel-based alloy welding wires for all welds, but this not only greatly increases the use of nickel-based alloy welding wires, increases welding costs, but also reduces the structural strength of the entire welded joint.

[0003] The paper "Additive manufacturing of functionally graded transition joints between ferritic and austenitic alloys" reports the deterioration of weld structure and performance when nickel-based alloys and carbon steel welding materials are mixed in a certain proportion. Due to the mutual dilution of the two welding materials, the mixed weld will harden significantly, thereby reducing the plastic toughness of the joint.

[0004] The Chinese patent document with publication number CN112122783A and publication date December 25, 2020, entitled "A method for laser butt welding of carbon steel-nickel alloy composite plates", discloses: under the condition that the construction space is limited and the composite layer must be welded first, the connection of the composite layer is achieved by laser self-melting or wire welding. However, it focuses on the problem that the composite plate cannot be welded on one side under this welding sequence, and does not pay attention to the performance changes of the mixed weld of nickel-based alloy and carbon steel.

[0005] The Chinese patent document with publication number CN113042895A and publication date June 29, 2021, entitled "A welding method for a nickel-steel composite structure" discloses: when the composite layer is welded first, laser autogenous welding is also used to complete the connection of the composite layer, and then cold metal transition welding is used to weld the adjacent welds, thereby completing the connection of the nickel-based alloy composite plate under this welding sequence. However, it mainly targets the problem of decreased corrosion resistance of the composite layer caused by element migration at the interface between the composite layer and the base layer, and also does not solve the problem of decreased toughness of the mixed weld of nickel-based alloy and carbon steel.

[0006] Furthermore, the above-mentioned patents all apply laser self-melting or wire-filling welding when welding composite plates. Such welding methods require very high assembly accuracy of components, and the equipment is expensive, the operation is cumbersome, and the maintenance is difficult. Summary of the invention

[0007] One of the purposes of the present invention is to provide a welding method for nickel-based alloy composite plates. The method effectively reduces the excessive melting of nickel-based alloy elements in the first weld of carbon steel through the coordinated design of groove design and welding method, which can greatly improve the toughness of the weld and achieve reliable connection of the composite plate. At the same time, since the optimization method of the present invention adopts mixed metal filling, the welding cost can be greatly reduced while improving the structural strength of the weld.

[0008] In order to achieve the above object, the present invention provides a welding method for a nickel-based alloy composite plate, wherein the nickel-based alloy composite plate comprises a substrate layer and a nickel-based alloy composite layer, and a transition layer is provided at a bonding interface between the substrate layer and the nickel-based alloy composite layer; the welding method comprises the steps of:

[0009] A trapezoidal groove is processed at the position corresponding to the base material layer on the welding section of the nickel-based alloy composite plate; a U-shaped groove is processed at the position corresponding to the transition layer on the welding section of the nickel-based alloy; and no groove is processed at the position corresponding to the nickel-based alloy composite material layer on the welding section of the nickel-based alloy composite plate;

[0010] Using a nickel-based alloy welding wire that matches the nickel-based alloy composite material layer, welding the nickel-based alloy composite material layer by single tungsten-polar argon arc welding to form a composite material layer weld;

[0011] Using a nickel-based alloy welding wire that matches the nickel-based alloy composite material layer, the transition layer is welded by single tungsten-polar argon arc welding to form a transition layer weld;

[0012] The substrate layer is welded to form a substrate layer weld, wherein a first weld pass of the substrate layer is welded by double tungsten inert gas arc welding.

[0013] In the present invention, the groove of the corresponding base material layer is designed to be trapezoidal, which can ensure the operability of the base material layer weld during double tungsten electrode argon arc welding.

[0014] Furthermore, in the welding method for nickel-based alloy composite plates of the present invention, the distance b between the bottom of the trapezoidal groove and the bonding interface between the substrate layer and the nickel-based alloy composite layer is 4 1-2mm.

[0015] Furthermore, in the welding method for nickel-based alloy composite plates of the present invention, the angle α between the inclined portion of the trapezoidal groove and the vertical direction is ≥ (1.5b 1 )°, where b 1 It indicates the distance from the surface of the substrate layer to the bonding interface between the substrate layer and the nickel-based alloy composite layer, and its unit parameter is mm.

[0016] Furthermore, in the welding method for nickel-based alloy composite plates of the present invention, the bottom single side width w of the trapezoidal groove is 2 ≥(5+0.1b 1 ), where b 1 It indicates the distance from the surface of the substrate layer to the bonding interface between the substrate layer and the nickel-based alloy composite layer, and its unit parameter is mm.

[0017] Furthermore, in the welding method for nickel-based alloy composite plates of the present invention, the single-side width w of the U-shaped groove is 1 0.5-1mm.

[0018] Furthermore, in the welding method for nickel-based alloy composite plates of the present invention, the radius r of the arc portion of the U-shaped groove is ≥ 0.5w 1 , where w 1 It represents the single side width of the U-shaped groove, and its unit parameter is mm.

[0019] In this embodiment, due to the poor fluidity of the molten pool of the nickel-based alloy, in order to ensure the good formation of the base layer weld and avoid defects such as unfused bottom of the molten pool, the transition layer weld position should be processed into a U-shaped groove, where the top single side width w 1 Controlled within the range of 0.5 to 1 mm.

[0020] Furthermore, in the welding method for nickel-based alloy composite plates described in the present invention, in the step of welding the nickel-based alloy composite layer by single tungsten electrode argon arc welding: a single-sided welding and double-sided forming process is adopted, the welding voltage is controlled to be 10-12V, the welding current is 80-110A, the welding speed is 90-110mm / min, and the wire feeding speed is 0.4-0.8m / min.

[0021] Furthermore, in the welding method for nickel-based alloy composite plates of the present invention, in the step of welding the nickel-based alloy composite material layer by single tungsten electrode argon arc welding: controlling the assembly gap w 3 =(3-2w1 )mm,w 1 Indicates the single side width of the U-shaped groove.

[0022] Furthermore, in the welding method for nickel-based alloy composite plates described in the present invention, in the step of welding the transition layer using single tungsten electrode argon arc welding: the welding voltage is controlled to be 7-10V, the welding current is 50-80A, the welding speed is 50-70mm / min, and the wire feeding speed is 0.2-0.6m / min.

[0023] In this embodiment, since the nickel-based alloy has a high alloying element content, in order to reduce the amount of alloying elements melted into the base layer weld, especially the carbon steel weld that is in direct contact with the transition layer weld, the above welding specifications should be adopted to reduce the top width of the transition layer weld.

[0024] Furthermore, in the welding method for nickel-based alloy composite plates described in the present invention, in the step of welding the first weld of the substrate layer using double tungsten electrode argon arc welding: the tungsten electrode arrangement direction is parallel to the welding direction, the tungsten electrode spacing is controlled to be 1-1.5 mm, the welding voltage is 13.0-15.0 V, the welding current is 260-300 A, the welding speed is 270-300 mm / min, the wire feeding speed is 6.0-7.0 m / min, and the welding gun is tilted 15-20° against the welding direction.

[0025] In this embodiment, due to the high content of alloying elements in the nickel-based alloy, the dilution rate control requirement of the first weld of the base material layer is very high, so double tungsten inert gas arc welding is used to minimize the welding penetration, and the center line of the weld is set at the center of the trapezoidal groove for operability. The transition layer weld obtained by the special design process can ensure that the dilution level of the carbon steel weld is less than 2.0% relative to the composite weld, thereby ensuring that the structure of the weld will not be transformed into martensite as a whole, and still maintain good plasticity and toughness.

[0026] Furthermore, in the welding method for nickel-based alloy composite plates described in the present invention, in the step of welding the substrate layer, single tungsten electrode argon arc welding is used to weld other welds except the first weld, and the welding voltage of the single tungsten electrode argon arc welding is controlled to be 13-16V, the welding current is 180-240A, the welding speed is 120-180mm / min, and the wire feeding speed is 1.8-3.0m / min.

[0027] The welding method for nickel-based alloy composite plates of the present invention has the following advantages and beneficial effects compared with the prior art:

[0028] The welding method described in the present invention can realize the reliable connection of nickel-based alloy composite plate components in the order of composite layer first welding, significantly reduce the dilution rate of the substrate layer-nickel-based alloy mixed weld, and effectively improve the impact toughness of the joint weld.

[0029] The welding method of the present invention uses mixed welding materials for filling during the welding process, which significantly reduces the welding cost while ensuring the structural strength of the joint. At the same time, arc welding is used for welding each layer of weld seam, which is simple to operate, has low equipment requirements, and has good scalability.

[0030] The invention can be applied to the multi-layer and multi-pass welding connection process of single-sided nickel-based alloy medium-thick composite plates with a composite plate thickness greater than or equal to 1 mm used in the fields of petroleum, chemical industry, light industry, marine engineering, nuclear industry, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 The figure schematically shows the groove diagram used in the type welding method of the nickel-based alloy composite plate described in the present invention.

[0032] Figure 2 The cross-sectional morphology of the optimized joint of the nickel-based alloy composite plate in the embodiment of the method of the present invention is shown. DETAILED DESCRIPTION

[0033] The welding method for the nickel-based alloy composite plate of the present invention will be further explained and illustrated below in conjunction with specific embodiments and the accompanying drawings of the specification. However, such explanation and illustration do not constitute an improper limitation on the technical solution of the present invention.

[0034] The object of the present invention is to provide a welding method for nickel-based alloy composite plates. Figure 1 Shows two spliced ​​nickel-based alloy composite plates A and B. Figure 1 The dotted line O in the figure represents a joint. The nickel-based alloy composite plate comprises a carbon steel substrate layer 1 and a nickel-based alloy composite material layer 2. A transition layer is provided at the interface between the carbon steel substrate layer and the nickel-based alloy composite material layer. Figure 1 The symbol "b 1 " represents the distance between the surface of the carbon steel substrate layer and the interface between it and the nickel-based alloy composite layer. 2 ” refers to the distance between the surface of the nickel-based alloy composite layer and the bonding interface between it and the carbon steel substrate layer.

[0035] In a specific embodiment, a nickel-based alloy composite plate with the grade of Incoloy825 / X52 can be used, that is, the base material is X52, and the nickel-based alloy composite material is Incoloy825. The thickness of the nickel-based alloy composite plate is 13 mm, wherein the nickel-based alloy composite plate has a thickness of 13 mm. 2 3mm, b 1 is 10mm.

[0036] In some embodiments, a welding method for a nickel-based alloy composite plate comprises the steps of:

[0037] 100: Processing at the welding position of two spliced ​​nickel-based alloy composite plates A and B as follows Figure 1 The groove shown. Among them, a trapezoidal groove is processed at the position corresponding to the base material layer on the welding section of the nickel-based alloy composite plate, and the trapezoidal groove includes a vertical inclined portion 7 and a horizontal inclined portion 8 arranged in sequence. A U-shaped groove is processed at the position corresponding to the transition layer on the welding section of the nickel-based alloy, and the U-shaped groove includes a vertical portion 9 and a transition arc 10 arranged in sequence; the groove is not processed at the position corresponding to the nickel-based alloy composite layer on the welding section of the nickel-based alloy composite plate, and the blunt edge is retained, that is, the welding surface of the nickel-based alloy composite layer is a vertical plane 11, Figure 1 The symbol "b 3 " represents the thickness of the blunt edge. In a specific example, b 3 It can be 2mm.

[0038] 200: The nickel-based alloy composite material layer is welded by single tungsten electrode argon arc welding, and a nickel-based alloy welding wire matching the nickel-based alloy composite material layer is used to form a composite material layer weld 3.

[0039] 300: The transition layer is welded by single tungsten electrode argon arc welding, and a nickel-based alloy welding wire matching the nickel-based alloy composite material layer is used to form a transition layer weld 4.

[0040] 400: The first weld bead of the substrate layer is welded by double tungsten inert gas arc welding to form a first weld seam 5 of the substrate layer.

[0041] 500: Use single tungsten inert gas arc welding to fill other welds of the base material layer. The welding wire used is a carbon steel welding wire that matches the carbon steel base material layer to form other welds 6 of the base material layer.

[0042] Preferably, in some embodiments, the distance b between the bottom of the trapezoidal groove and the bonding interface between the substrate layer and the nickel-based alloy composite layer is 4 1-2mm.

[0043] Preferably, in some embodiments, the angle between the inclined portion of the trapezoidal groove and the vertical direction is α≥(1.5b 1 )°, where b 1 It indicates the distance from the surface of the substrate layer to the bonding interface between the substrate layer and the nickel-based alloy composite layer, and its unit parameter is mm.

[0044] Preferably, in some embodiments, the bottom single side width w of the trapezoidal groove is 2 ≥(5+0.1b 1 ), where b 1It indicates the distance from the surface of the substrate layer to the bonding interface between the substrate layer and the nickel-based alloy composite layer, and its unit parameter is mm.

[0045] Preferably, in some embodiments, in order to take into account both welding forming and dilution rate control, the transition layer weld is processed into a U-shape between the inner and outer sides, and the single-side width w of the U-shaped groove is 1 0.5-1mm.

[0046] Preferably, in some embodiments, the radius of the arc portion of the U-shaped groove is r≥0.5w 1 , where w 1 It represents the single side width of the U-shaped groove, and its unit parameter is mm.

[0047] Preferably, in some embodiments, in step 200, the welding wire is a nickel-based alloy welding wire ERNiCrMo-3 that matches the composite layer, and the welding method adopts single tungsten electrode argon arc welding to weld the nickel-based alloy composite layer weld 3, using a single-sided welding and double-sided forming process, controlling the welding voltage to 10-12V, the welding current to 80-110A, the welding speed to 90-110mm / min, the wire feeding speed to 0.4-0.8m / min, and controlling the assembly gap w 3 =(3-2w 1 )mm,w 1 Indicates the single side width of the U-shaped groove.

[0048] In step 300, the welding wire used is a nickel-based alloy welding wire ERNiCrMo-3 with a performance not lower than that of the composite layer. The welding method adopts single tungsten electrode argon arc welding to form a transition layer weld 4. The welding voltage is controlled to be 7-10V, the welding current is 50-80A, the welding speed is 50-70mm / min, and the wire feeding speed is 0.2-0.6m / min.

[0049] In step 400, a carbon steel welding wire ER50-6 matching the base material is used for welding, and a double tungsten electrode argon arc welding is used for welding the first weld of the base material layer. The tungsten electrode arrangement direction is parallel to the welding direction, the tungsten electrode spacing is controlled to be 1-1.5 mm, the welding voltage is 13.0-15.0 V, the welding current is 260-300 A, the welding speed is 270-300 mm / min, the wire feeding speed is 6.0-7.0 m / min, and the welding gun is tilted 15-20° against the welding direction.

[0050] In step 500, carbon steel welding wire ER50-6 matching the base material is used to weld the other welds of the base layer except the first weld. The welding method adopts single tungsten inert gas arc welding, the welding voltage is 13-16V, the welding current is 180-240A, the welding speed is 120-180mm / min, and the wire feeding speed is 1.8-3.0m / min.

[0051] In order to further reflect the preferred implementation of this case, Table 1 lists the characteristic parameters of the grooves used in the preferred embodiments 1-5 of the present invention.

[0052] Table 1.

[0053]

[0054]

[0055] Table 2 lists the welding process parameters used in step 200 of forming a composite material layer weld in preferred embodiments 1-5 of the present invention.

[0056] Table 2.

[0057]

[0058] Table 3 lists the welding process parameters used in step 300 of forming the transition layer weld in preferred embodiments 1-5 of the present invention.

[0059] Table 3.

[0060]

[0061] Table 4 lists the welding process parameters used in step 400 of forming the first weld of the substrate layer in preferred embodiments 1-5 of the present invention.

[0062] Table 4.

[0063]

[0064] Table 5 lists the preferred welding process parameters used in step 500 of filling other welds of the substrate layer according to the present invention.

[0065] Table 5

[0066]

[0067] In addition, in order to prove the implementation effect of the preferred embodiment, Table 6 lists the Cr element content of each layer of the base material and the weld in the joint of the nickel-based alloy composite plate obtained by welding in Example 1 of the present invention. By calculation, it can be obtained that the dilution rate of the carbon steel weld directly contacting the transition layer relative to the weld of the composite material layer is 1.95% (lower than 2.0%).

[0068] Table 6.

[0069]

[0070]

[0071] Figure 2 The cross-sectional morphology of the optimized joint of the nickel-based alloy composite plate in the embodiment of the method of the present invention is shown.

[0072] from Figure 2 It can be seen that the optimized joint of the nickel-based alloy composite plate is well fused and has no welding defects. At the same time, due to the application of the method of the present invention, the area of ​​the nickel-based alloy weld of the transition layer and the composite layer is small. Therefore, compared with the full nickel-based alloy welding material filling solution, the method of the present invention can greatly reduce the use of nickel-based alloy welding materials, reduce welding costs, improve structural strength, and improve welding efficiency.

[0073] It should be noted that the combination of the various technical features in this case is not limited to the combination described in the claims of this case or the combination described in the specific embodiments. All technical features recorded in this case can be freely combined or combined in any way unless there is a contradiction between them.

[0074] It should also be noted that the above-listed embodiments are only specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and similar changes or modifications made therewith can be directly derived or easily associated with the contents disclosed by those skilled in the art from the present invention, and all should belong to the protection scope of the present invention.

Claims

1. A welding method for a nickel-based alloy composite plate, wherein the nickel-based alloy composite plate comprises a substrate layer and a nickel-based alloy composite layer, wherein a transition layer is provided at a bonding interface between the substrate layer and the nickel-based alloy composite layer; characterized in that: The welding method comprises the steps of: A trapezoidal groove is processed at the position corresponding to the base material layer on the welding section of the nickel-based alloy composite plate; a U-shaped groove is processed at the position corresponding to the transition layer on the welding section of the nickel-based alloy; and no groove is processed at the position corresponding to the nickel-based alloy composite material layer on the welding section of the nickel-based alloy composite plate; Using a nickel-based alloy welding wire that matches the nickel-based alloy composite material layer, welding the nickel-based alloy composite material layer by single tungsten-polar argon arc welding to form a composite material layer weld; Using a nickel-based alloy welding wire that matches the nickel-based alloy composite material layer, the transition layer is welded by single tungsten-polar argon arc welding to form a transition layer weld; The substrate layer is welded to form a substrate layer weld, wherein a first weld pass of the substrate layer is welded by double tungsten inert gas arc welding.

2. The welding method for nickel-based alloy composite plate according to claim 1, characterized in that: The distance b4 between the bottom of the trapezoidal groove and the bonding interface between the substrate layer and the nickel-based alloy composite layer is 1-2 mm.

3. The welding method for nickel-based alloy composite plate according to claim 1, characterized in that: The angle α between the inclined portion of the trapezoidal groove and the vertical direction is ≥(1.5b1)°, where b1 represents the distance from the surface of the substrate layer to the bonding interface between the substrate layer and the nickel-based alloy composite layer, and its unit parameter is mm.

4. The welding method for nickel-based alloy composite plate according to claim 1, characterized in that: The bottom single-side width w2 of the trapezoidal groove is ≥ (5+0.1b1), where b1 represents the distance from the surface of the substrate layer to the bonding interface between the substrate layer and the nickel-based alloy composite layer, and its unit parameter is mm.

5. The welding method for nickel-based alloy composite plate according to claim 1, characterized in that: The single side width w1 of the U-shaped groove is 0.5-1 mm.

6. The welding method for nickel-based alloy composite plate according to claim 1, characterized in that: The radius r of the arc portion of the U-shaped groove is ≥0.5w1, where w1 represents the single-side width of the U-shaped groove, and its unit parameter is mm.

7. The welding method for nickel-based alloy composite plate according to claim 1, characterized in that: In the step of welding the nickel-based alloy composite layer by single tungsten electrode argon arc welding: a single-sided welding and double-sided forming process is adopted, the welding voltage is controlled to be 10-12V, the welding current is 80-110A, the welding speed is 90-110mm / min, and the wire feeding speed is 0.4-0.8m / min.

8. The welding method for nickel-based alloy composite plate according to claim 1, characterized in that: In the step of welding the nickel-based alloy composite layer by single tungsten electrode argon arc welding: the assembly gap w3 is controlled to be (3-2w1) mm, where w1 represents the single-side width of the U-shaped groove.

9. The welding method for nickel-based alloy composite plate according to claim 1, characterized in that: In the step of welding the transition layer by single tungsten electrode argon arc welding: the welding voltage is controlled to be 7-10V, the welding current is 50-80A, the welding speed is 50-70mm / min, and the wire feeding speed is 0.2-0.6m / min.

10. The welding method for nickel-based alloy composite plate according to claim 1, characterized in that: In the step of welding the first weld of the substrate layer by double tungsten electrode argon arc welding: the tungsten electrode arrangement direction is parallel to the welding direction, the tungsten electrode spacing is controlled to be 1-1.5mm, the welding voltage is 13.0-15.0V, the welding current is 260-300A, the welding speed is 270-300mm / min, the wire feeding speed is 6.0-7.0m / min, and the welding gun is tilted 15-20° against the welding direction.

11. The welding method for nickel-based alloy composite plate according to claim 1, characterized in that: In the step of welding the substrate layer, single tungsten electrode argon arc welding is used to weld the other welds except the first weld. The welding voltage of single tungsten electrode argon arc welding is controlled to be 13-16V, the welding current is 180-240A, the welding speed is 120-180mm / min, and the wire feeding speed is 1.8-3.0m / min.

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