Method for vacuum electron beam welding production of stainless steel clad plate

Abstract

The present application relates to dissimilar metal composite material technical field, specifically to a kind of vacuum electron beam welding production stainless steel clad plate method, comprising the following steps: (1) preparation two groups of composite blank, composite blank preparation method is to place stainless steel plate in the middle convex position of carbon steel plate, the joint of carbon steel plate and stainless steel plate is welded using vacuum electron beam welding machine;(2) one group of composite blank is placed in the way that stainless steel plate faces upwards, then carbon steel frame is sleeved on the composite blank, and baking-free release agent is coated on the stainless steel plate of composite blank, another group of composite blank is invertedly buckled on the carbon steel frame in the way that stainless steel plate faces downwards, the joint of composite blank group and carbon steel frame is welded using vacuum electron beam welding machine, and blank preparation is completed.The present application uses symmetrical blank preparation method, uses baking-free release agent, does not need to bake release agent, and is welded in higher vacuum degree environment, and higher composite strength metal composite material can be obtained using traditional rolling process.

Description

Technical Field

[0001] This invention relates to the field of dissimilar metal composite materials technology, specifically to a method for producing stainless steel composite plates by vacuum electron beam welding. Background Technology

[0002] Currently, the production of dissimilar metal composite plates mainly employs submerged arc welding followed by post-weld vacuuming using a mechanical pump. Patent application CN104138920A, "A method for manufacturing rolled metal composite plates with pipeline steel as the base material," requires drying the release agent, sealing the billet around its perimeter using submerged arc welding, and then evacuating the billet after welding. However, submerged arc welding consumes a large amount of welding wire and flux, and the vacuum level achieved by the mechanical vacuum pump is difficult to reach 1.0*10⁻⁶. -2 Below Pa, the quality of the processed dissimilar metal composite plates often fluctuates.

[0003] Some companies also use vacuum electron beam welding for single-sided billet preparation and single-sided rolling. However, single-sided rolling has high requirements for heating and rolling processes, and also puts a greater impact on the rolling mill, resulting in an unstable rolling process. Invention patent applications CN108213873A "A method for producing stainless steel composite steel plates for bridges" and CN110539066A "A method for vacuum electron beam assembly and sealing of high-alloy steel-titanium composite plates" both require drying the release agent and milling grooves on the upper and lower substrates. The area of ​​the grooves is the same as the area of ​​the composite plate, resulting in a large milling area and low milling efficiency. Summary of the Invention

[0004] To address the technical problems of existing methods using vacuum electron beam welding for single-sided billet preparation and single-sided rolling, such as the need to dry the release agent and the instability of the rolling process, this invention provides a method for producing stainless steel composite plates using vacuum electron beam welding. This invention adopts a symmetrical billet preparation method, uses a drying-free release agent, eliminates the need to dry the release agent, and welds under a high vacuum environment. It can obtain a metal composite material with higher composite strength using traditional rolling processes.

[0005] The technical solution of this invention is as follows: A method for producing stainless steel composite plates by vacuum electron beam welding. The stainless steel composite plate includes a carbon steel frame and a composite billet assembly. The composite billet assembly includes two sets of composite billets arranged opposite each other. Each set of composite billets includes carbon steel plates and stainless steel plates stacked on top of each other. The carbon steel plates are in the shape of a boss with a high center and low perimeter. The stainless steel plates have the same dimensions as the boss in the center of the carbon steel plates. The stainless steel plates of the two sets of composite billets are in contact with each other through a drying-free release agent layer to form a stacked structure with the center and perimeter recessed inward. The carbon steel frame is embedded in the recessed position in the center of the composite billet assembly. The production method of stainless steel composite plates includes the following steps: (1) Two sets of composite billets were prepared. The composite billet preparation method was to place the stainless steel plate in the middle of the carbon steel plate and weld the joint between the carbon steel plate and the stainless steel plate using a vacuum electron beam welding machine. (2) Place a set of composite billets with the stainless steel plate facing up, then put the carbon steel frame on the composite billet, and apply a drying-free release agent to the stainless steel plate of the composite billet. Then, place another set of composite billets upside down on the carbon steel frame with the stainless steel plate facing down, and use a vacuum electron beam welding machine to perform circumferential welding on the joint between the composite billet set and the carbon steel frame to complete the billet preparation.

[0006] Furthermore, the dimensions of the carbon steel plate are calculated using the following formula: L 碳钢板 =L 不锈钢板 +100, W 碳钢板 =W 不锈钢板 +100; In the formula L 碳钢板 W 碳钢板 The length, width, and thickness of the carbon steel plate are represented in mm, respectively; L 不锈钢板 W 不锈钢板 The length, width, and thickness of the stainless steel sheet are represented in mm, respectively. The shape and size of the raised part in the middle of the carbon steel plate are the same as those of the stainless steel plate, and the thickness difference between the raised part in the middle of the carbon steel plate and the edge part is 20mm.

[0007] Furthermore, the outer length of the carbon steel frame is the same as the length of the carbon steel plate, and the outer width of the carbon steel frame is the same as the width of the carbon steel plate. The inner length of the carbon steel frame is the same as the length of the stainless steel plate, and the inner width of the carbon steel frame is the same as the width of the stainless steel plate. The thickness of the carbon steel frame is calculated using the following formula: H 碳钢框 =2×H 不锈钢板 +40, where H 碳钢框 H 不锈钢板 These represent the thickness of the carbon steel frame and the stainless steel plate, respectively, in mm.

[0008] Furthermore, both stainless steel and carbon steel plates undergo overall milling before use to remove all iron oxide scale from the surface.

[0009] Furthermore, after combining the stainless steel plate and the carbon steel plate, a three-stage vacuum pump is used to evacuate the vacuum to 1.0 × 10⁻⁶. -2 Sealing below Pa.

[0010] Furthermore, if the weld penetration depth of the stainless steel plate and carbon steel plate is greater than or equal to 10mm, and the penetration depth fails to meet the standard after flaw detection, it needs to be re-welded until the penetration depth reaches more than 10mm.

[0011] Furthermore, the gaps at the joint surfaces of the stainless steel plate and the carbon steel plate, and the gaps at the joint surfaces of the carbon steel frame and the composite billet, are all less than or equal to 0.4 mm.

[0012] Furthermore, before use, the upper and lower surfaces of the carbon steel frame are polished to remove any residual iron oxide scale and oil stains.

[0013] Furthermore, after the composite billet assembly is combined with the carbon steel frame, a three-stage vacuum pump is used to evacuate the vacuum to 1.0 × 10⁻⁶. -2 Below Pa, the mating surfaces of the upper surface of the carbon steel frame and the upper composite billet, and the mating surfaces of the lower surface of the carbon steel frame and the lower composite billet are welded respectively.

[0014] Furthermore, the weld penetration depth of the composite billet assembly and the carbon steel frame must be greater than or equal to 30mm. If the penetration depth fails to meet the standard after flaw detection, it needs to be re-welded until the penetration depth reaches more than 30mm.

[0015] The beneficial effects of this invention are as follows: The method of this invention first prepares two sets of single-sided composite billets, and then combines the two sets of single-sided composite billets using a symmetrical billet preparation method. A stainless steel composite plate with high composite strength can be obtained using a traditional rolling process. This invention uses a drying-free release agent between the two sets of composite billets, eliminating the need for drying the release agent and reducing the release agent drying process. Electron beam welding is used as the welding method. Because the electron beam welding machine uses a three-stage vacuum pump for evacuation, electron beam welding has a higher vacuum degree compared to an external evacuation pump. Furthermore, electron beam welding does not consume a large amount of welding wire and flux, and there is no need for post-weld evacuation of the billets; the welded billets can be directly loaded into the furnace for rolling. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a cross-sectional schematic diagram of the composite blank according to a specific embodiment of the present invention.

[0018] Figure 2 This is a cross-sectional schematic diagram of a stainless steel composite plate according to a specific embodiment of the present invention.

[0019] Figure 3 This is a schematic diagram of the structure of a stainless steel composite plate according to a specific embodiment of the present invention.

[0020] In the diagram, 1-carbon steel frame, 2-carbon steel plate, 3-stainless steel plate, 4-no-drying release agent layer, 5-composite blank. Detailed Implementation

[0021] To enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0022] Example 1 A stainless steel clad plate produced by vacuum electron beam welding, comprising a "hui"-shaped carbon steel frame 1 and a clad blank group, wherein the clad blank group comprises two sets of oppositely arranged clad blanks 5, each set of clad blanks comprises a carbon steel plate 2 and a stainless steel plate 3 stacked up and down, the carbon steel plate 2 is in a boss shape with a high middle part and low periphery, the size of the stainless steel plate 3 is consistent with the size of the middle protruding part of the carbon steel plate 2, the stainless steel plates 3 of the two sets of clad blanks are in contact through a non-drying isolating agent layer 4 to form a laminated structure with an inward depression at the periphery of the middle part, and the carbon steel frame 1 is embedded in the depression position in the middle of the clad blank group; Wherein, the size of the carbon steel plate 2 is calculated according to the following formula: L 碳钢板 =L 不锈钢板 +100, W 碳钢板 =W 不锈钢板 +100; wherein, L 碳钢板 , W 碳钢板 sequentially represent the length, width and thickness of the carbon steel plate, with the unit being mm; L 不锈钢板 , W 不锈钢板 sequentially represent the length, width and thickness of the stainless steel plate, with the unit being mm; the shape and size of the middle protruding part of the carbon steel plate 2 are consistent with those of the stainless steel plate, and the thickness difference between the middle protruding part and the edge part of the carbon steel plate 2 is 20 mm; the outer perimeter of the carbon steel frame 1 is consistent with the length of the carbon steel plate 2, and the outer width of the carbon steel frame 1 is consistent with the width of the carbon steel plate 2; the inner perimeter length of the carbon steel frame 1 is consistent with the length of the stainless steel plate 3, and the inner perimeter width of the carbon steel frame 1 is consistent with the width of the stainless steel plate 3; the thickness of the carbon steel frame 1 is calculated according to the following formula: H 碳钢框 =2×H 不锈钢板 +40, H 碳钢框 and H 不锈钢板 respectively represent the thickness of the carbon steel frame and the thickness of the stainless steel plate, with the unit being mm.

[0023] Example 2 A vacuum electron beam welding production method for a stainless steel composite plate according to Embodiment 1 includes the following steps: (1) Prepare two cubic carbon steel plates and two cubic stainless steel plates and mill them as a whole. The milling requirement is to remove all iron oxide scale from the surface. Continue milling the carbon steel plate, milling 50mm on each side of the carbon steel plate, with a milling depth of 20mm. After milling, the carbon steel plate is a boss shape with a high center and low sides. Take one stainless steel plate and one carbon steel plate, place the stainless steel plate on the middle protrusion of the carbon steel plate, and make the side of the stainless steel plate and the side of the carbon steel plate after milling strictly aligned, and the gap between the mating surfaces should not be greater than 0.4mm. Then put the assembled blank into a vacuum electron beam welding machine and use a three-stage vacuum pump to evacuate to 1.0*10 -2 For welds with a penetration depth below Pa, flaw detection is used to ensure the weld penetration depth is greater than or equal to 10 mm. Welds with insufficient penetration depth need to be re-welded until the penetration depth reaches 10 mm or more, resulting in a set of composite blanks. Another set of composite blanks is prepared using the same method.

[0024] (2) Place one set of composite blanks with the stainless steel plate facing upwards. Then, after cleaning the upper and lower surfaces of the carbon steel frame, place it onto the composite blanks. Apply a no-drying release agent to the stainless steel plate of the composite blanks. Then, place another set of composite blanks upside down onto the carbon steel frame with the stainless steel plate facing downwards. The upper and lower sets of composite blanks and the sides of the carbon steel frame must be strictly aligned, and the gap between the upper and lower mating surfaces must not exceed 0.4 mm. Then, place the assembled blanks into a vacuum electron beam welding machine and use a three-stage vacuum pump to evacuate to 1.0*10. -2 For sealing welds below Pa, flaw detection is used to control the weld penetration depth to be greater than or equal to 30mm. If the penetration depth does not meet the standard, it needs to be re-welded until the penetration depth reaches more than 30mm to obtain a stainless steel composite plate.

[0025] The stainless steel composite plate from Example 1 was sent to the rolling line and rolled using a conventional rolling process. After the steel plate cooled to room temperature, the four sides of the steel plate were cut, naturally separating it into two metal composite plates.

[0026] The mechanical properties of the rolled metal composite plate were tested, with a metal composite plate obtained by submerged arc welding instead of vacuum electron beam welding used as a control. The test results are as follows: The interfacial shear strength of the metal composite plate obtained after rolling in Example 2 can reach 380 MPa, while the interfacial shear strength of the metal composite plate obtained after rolling the composite billet prepared by submerged arc welding is only 320 MPa.

[0027] In summary, this invention reduces milling waste in composite billet substrates, solves the problem of drying composite billet group release agent affecting processing efficiency, and produces high-quality dissimilar metal composite plates.

[0028] Although the present invention has been described in detail with reference to the accompanying drawings and preferred embodiments, the present invention is not limited thereto. Various equivalent modifications or substitutions can be made to the embodiments of the present invention by those skilled in the art without departing from the spirit and essence of the invention, and such modifications or substitutions should all be within the scope of the present invention. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should also be covered within the protection scope of the present invention.

Claims

1. A method for producing stainless steel composite plates by vacuum electron beam welding, characterized in that, The stainless steel composite plate includes a carbon steel frame and a composite billet assembly. The composite billet assembly includes two sets of composite billets arranged opposite each other. Each set of composite billets includes carbon steel plates and stainless steel plates stacked on top of each other. The carbon steel plates are in the shape of a raised platform with a high center and low perimeter. The stainless steel plates have the same dimensions as the raised part in the center of the carbon steel plates. The stainless steel plates of the two sets of composite billets are in contact with each other through a drying-free release agent layer to form a stacked structure with the center and perimeter recessed inward. The carbon steel frame is embedded in the recessed position in the center of the composite billet assembly. The production method of stainless steel composite plates includes the following steps: (1) Two sets of composite billets were prepared. The method for preparing the composite billets was to place the stainless steel plate in the middle of the protruding position of the carbon steel plate. After the stainless steel plate and the carbon steel plate were combined, a three-stage vacuum pump was used to evacuate to 1.0×10. -2 For sealing welding below Pa, a vacuum electron beam welding machine is used to weld the joint between carbon steel plate and stainless steel plate, and the weld penetration depth between stainless steel plate and carbon steel plate is greater than or equal to 10mm. (2) Place a set of composite billets with the stainless steel plate facing up, then put the carbon steel frame on the composite billet, and apply a drying-free release agent to the stainless steel plate of the composite billet. Then, place another set of composite billets upside down on the carbon steel frame with the stainless steel plate facing down, and use a vacuum electron beam welding machine to perform circumferential welding on the joint between the composite billet set and the carbon steel frame to complete the billet preparation.

2. The method as described in claim 1, characterized in that, The dimensions of carbon steel plates are calculated using the following formula: L carbon steel plate = L stainless steel plate + 100, W carbon steel plate = W stainless steel plate + 100; In the formula, L carbon steel plate and W carbon steel plate represent the length and width of the carbon steel plate, respectively, in mm; L stainless steel plate and W stainless steel plate represent the length and width of the stainless steel plate, respectively, in mm. The shape and size of the raised part in the middle of the carbon steel plate are the same as those of the stainless steel plate, and the thickness difference between the raised part in the middle of the carbon steel plate and the edge part is 20mm.

3. The method as described in claim 2, characterized in that, The outer length of the carbon steel frame is the same as the length of the carbon steel plate, and the outer width of the carbon steel frame is the same as the width of the carbon steel plate. The inner length of the carbon steel frame is the same as the length of the stainless steel plate, and the inner width of the carbon steel frame is the same as the width of the stainless steel plate. The thickness of the carbon steel frame is calculated using the following formula: Hcarbon steel frame = 2 × Hstainless steel plate + 40, where Hcarbon steel frame and Hstainless steel plate represent the thickness of the carbon steel frame and the stainless steel plate, respectively, in mm.

4. The method as described in claim 1, characterized in that, Both stainless steel and carbon steel plates undergo overall milling before use to remove all iron oxide scale from the surface.

5. The method as described in claim 1, characterized in that, The gap between the joint surface of the stainless steel plate and the carbon steel plate, and the gap between the joint surface of the carbon steel frame and the composite billet are all less than or equal to 0.4 mm.

6. The method as described in claim 1, characterized in that, Before use, grind the upper and lower surfaces of the carbon steel frame to remove any residual iron oxide scale and oil stains.

7. The method as described in claim 1, characterized in that, After the composite billet assembly is combined with the carbon steel frame, a three-stage vacuum pump is used to evacuate the vacuum to 1.0 × 10⁻⁶. -2 Below Pa, the mating surfaces of the upper surface of the carbon steel frame and the upper composite billet, and the mating surfaces of the lower surface of the carbon steel frame and the lower composite billet are welded respectively.

8. The method as described in claim 1, characterized in that, The weld penetration depth between the composite billet assembly and the carbon steel frame is greater than or equal to 30 mm.

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