A friction build-up welding method for enhancing the intercoat adhesion

Abstract

The present application relates to a kind of friction welding method of enhanced coating interfacial bonding force, comprising the following steps: the edge of the sheet is limited to be equipped on the outside of base material stick;Move base material stick and make it contact with substrate surface, and according to the gap between the bottom surface of edge of the sheet and substrate surface is set according to coating height;Rotating and pressing base material stick, and the bottom end of base material stick is friction with substrate and generates thermal deformation;Along the plane where substrate is located, the base material stick after deformation is translated, to form first coating;Edge of the sheet moves synchronously with base material stick, so that the surface of first coating is extruded by the extrusion part of the bottom surface of edge of the sheet to form tooth pattern.The present application can enhance the bonding force between coating, and can limit the bottom end of base material stick, to prevent the bottom end of base material stick from forming redundant edge of the sheet.

Description

Technical Field

[0001] This invention relates to the field of solid-state forming technology, and in particular to a friction welding method that can enhance the adhesion between coatings. Background Technology

[0002] Friction welding is a process that uses the frictional heat generated by the relative motion between a base rod and a substrate as a heat source to transfer the base rod to the surface of the substrate to form a weld overlay coating. During the weld overlay process, the base rod rotates and comes into contact with the surface of the substrate. The heat generated by the friction at the contact surface causes the materials on both sides of the bonding surface to reach a thermoplastic state. At this point, upsetting pressure is applied to achieve the connection between the base rod and the substrate. Simultaneously, the base rod moves linearly in a certain direction, thereby forming a coating on the surface of the substrate.

[0003] Friction welding suffers from redundant edge curling during coating formation, resulting in limited filament rod utilization and restricting the length of a single coating layer. Furthermore, when using friction welding for solid-state additive manufacturing, the relatively smooth interface between upper and lower coating layers leads to insufficient adhesion and poor longitudinal strength of the material. Summary of the Invention

[0004] This invention provides a friction welding method that can enhance the bonding force between coatings, and at least solves the problems of redundant curling at the bottom of the consumable rod and insufficient bonding force between coatings in the prior art.

[0005] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0006] A friction welding method is provided to enhance the adhesion between coatings.

[0007] A friction welding method for enhancing inter-coating adhesion, the method comprising the following steps:

[0008] The edge-curling limiter is fitted onto the outside of the base material bar;

[0009] Move the base material bar to contact the substrate surface, and set the gap between the bottom surface of the edge retainer and the substrate surface according to the coating height;

[0010] The base material rod is rotated and pressed down, causing the bottom end of the base material rod to rub against the substrate and generate thermal deformation;

[0011] The deformed base rod is translated along the plane of the substrate to form a first coating.

[0012] The edge-curling limiter moves synchronously with the base material bar, causing the first coating surface to be pressed by the extrusion part on the bottom surface of the edge-curling limiter to form serrations.

[0013] Optionally, at least the lower part of the bar channel of the crimping limiter is adapted to the outer diameter of the parent bar to limit redundant crimping at the bottom end of the parent bar.

[0014] Optionally, after the crimping limiter moves synchronously with the parent material bar, causing the first coating surface to be pressed by the extrusion portion on the bottom surface of the crimping limiter to form serrations, the method further includes:

[0015] A second coating is formed on the first coating and is metallurgically bonded to the first coating.

[0016] Optionally, the step of forming a second coating that is metallurgically bonded to the first coating on the first coating includes:

[0017] The parent material bar and the edge-curling limiter are moved vertically;

[0018] The base material rod is rotated and pressed down, causing the bottom end of the base material rod and the surface of the first coating to undergo severe deformation and soften into a plastic deformation flow;

[0019] The plastic deformation flow is pushed by the rotating parent material rod and forms an interlaced stirring structure with the tooth pattern;

[0020] The deformed base rod is translated along the plane containing the first coating to form a second coating on the surface of the first coating.

[0021] Optionally, the extrusion part is a serrated structure recessed into the bottom surface of the edge-curling limiter, each serration of the extrusion part is a right-angled triangle, and the tooth pattern is a convex tooth protruding outward from the surface of the first coating.

[0022] The step of the plastic deformation flow being pushed by the rotating parent material bar and forming an interlaced stirring structure with the toothed grooves includes:

[0023] The base material bar rotates toward the right-angled surface facing the saw teeth;

[0024] The plastic deformation flow fills the right angle on the outside of the protruding tooth under the pushing action of the base material rod.

[0025] Optionally, the extrusion part is a serrated structure that protrudes outward from the bottom surface of the edge-curling limiter, each serration of the extrusion part is a right-angled triangle, and the tooth pattern is a groove that is concave inward on the surface of the first coating.

[0026] The step of the plastic deformation flow being pushed by the rotating parent material rod and forming an interlaced stirring structure with the toothed pattern includes:

[0027] The base material bar rotates toward the inclined surface facing the saw teeth;

[0028] The plastic deformation flow fills the tooth groove under the pushing action of the base material rod.

[0029] Optionally, the step of the crimping limiter moving synchronously with the parent material bar, such that the first coating surface is pressed by the extrusion portion on the bottom surface of the crimping limiter to form serrations, includes:

[0030] Determine the direction of movement of the parent material bar;

[0031] Adjust the edge-pressing limiter so that the pressing part on the bottom surface of the edge-pressing limiter is located on the side opposite to the moving direction of the parent material bar;

[0032] The edge-pressing limiter is translated along the plane of the first coating, so that the extrusion part extrudes the surface of the first coating to form a tooth pattern.

[0033] Optionally, one end of the crimping limiter is connected to the machine head, and the step of translating the crimping limiter along the plane of the first coating to extrude the extrusion section to form a toothed texture on the surface of the first coating includes:

[0034] The machine head is controlled to drive the edge-curling limiter to move synchronously with the base material bar, so that the extrusion part of the edge-curling limiter end face extrudes the first coating surface to form teeth.

[0035] Optionally, the base material bar is connected to the rotating spindle via a clamp, and the step of rotating and pressing down the base material bar to cause the bottom end of the base material bar to rub against the substrate and generate thermal deformation includes:

[0036] The rotating spindle is controlled to drive the base material bar to rotate relative to the substrate, so that the bottom surface of the base material bar in contact with the substrate generates thermal deformation through friction and forms plastic deformation flow.

[0037] Optionally, it also includes:

[0038] The bottom end of the base material bar is cooled to prevent it from expanding due to heat.

[0039] Optionally, before moving the parent material bar to contact the substrate surface, the method further includes:

[0040] The surface of the substrate is processed to form a non-planar structure that is metallurgically bonded to the first coating.

[0041] Optionally, the surface of the substrate is processed by any one of wire cutting, electrical discharge machining, milling, knurling, or rough grinding.

[0042] The beneficial effects of this invention are:

[0043] The extrusion section at the bottom of the edge curling limiter can be used to extrude the coating surface to form a toothed texture. When the next coating is applied to its surface, an interleaved stirring structure can be formed to enhance the bonding force between the coatings. At the same time, by sleeved on the outside of the base rod, the inner wall of the edge curling limiter can be used to restrict the bottom of the base rod to prevent the plastic deformation flow at the bottom of the base rod from rolling upward and forming redundant curls during the rotation of the base rod. Attached Figure Description

[0044] 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, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0045] Figure 1 This is a schematic flowchart of the friction welding method for enhancing inter-coating adhesion according to the present invention.

[0046] Figure 2 This is a further schematic diagram of step S50 in the friction welding method for enhancing inter-coating adhesion of the present invention.

[0047] Figure 3 This is a further schematic diagram of step S60 in the friction welding method for enhancing inter-coating adhesion of the present invention.

[0048] Figure 4 This is a further schematic diagram of step S63 in the friction welding method for enhancing inter-coating adhesion of the present invention.

[0049] Figure 5 This is a further schematic flowchart of step S63 in the friction welding method for enhancing inter-coating adhesion of the present invention.

[0050] Figure 6 This is a schematic diagram of the friction welding device in this invention;

[0051] Figure 7 This is a front view of the friction welding device in this invention;

[0052] Figure 8 A cross-sectional view of the friction welding device in this invention (with the substrate removed);

[0053] Figure 9 A schematic diagram of the hem-rolling limiter in this invention;

[0054] Figure 10 Another angle structural diagram of the hem restrictor in this invention;

[0055] Figure 11 Front view of the hem restrictor in this invention;

[0056] Figure 12 A schematic diagram illustrating the combination of the substrate and coating in this invention;

[0057] Figure 13 A schematic diagram of the coating bonding in this invention;

[0058] Figure 14 A front view of the hem-rolling limiter structure according to another embodiment of the present invention;

[0059] Figure 15 A schematic diagram of the substrate and coating bonding in another embodiment of the present invention;

[0060] Figure 16 A schematic diagram of coating bonding according to another embodiment of the present invention;

[0061] Figure 17 This is a schematic flowchart of a friction welding method for enhancing inter-coating adhesion, according to another embodiment of the present invention.

[0062] Explanation of icon numbers:

[0063] 10-Substrate;

[0064] 20-base material rod;

[0065] 30 - First coating; 31 - Tooth pattern;

[0066] 40 - Edge curling limiter; 41 - Bar stock channel; 411 - First channel; 412 - Second channel; 42 - Extrusion section;

[0067] 70 - Second coating. Detailed Implementation

[0068] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0069] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0070] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0071] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0072] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0073] The invention will now be further described with reference to the accompanying drawings.

[0074] This invention provides a friction welding method that enhances the bonding force between coatings. The extrusion part at the bottom of the edge-curling limiter can be used to extrude the coating surface to form a toothed pattern. When a subsequent coating is applied to its surface, an interleaved stirring structure can be formed to enhance the bonding force between the coatings. At the same time, by sleeved on the outside of the base rod, the inner wall of the edge-curling limiter can restrict the bottom of the base rod to prevent the plastic deformation flow at the bottom of the base rod from rolling upward and forming redundant edges during rotation.

[0075] This invention provides a friction welding method that enhances the adhesion between coatings, comprising the following steps:

[0076] Step S10: Fit the edge-curling limiter 40 onto the outside of the base material bar 20;

[0077] Step S20: Move the base material rod 20 to contact the surface of the substrate 10, and set the gap between the bottom surface of the edge retainer 40 and the surface of the substrate 10 according to the coating height;

[0078] Step S30: Rotate and press down the base material rod 20 to cause the bottom end of the base material rod 20 to rub against the substrate 10 and generate thermal deformation;

[0079] Step S40: Translate the deformed base rod 20 along the plane of the substrate 10 to form the first coating 30;

[0080] Step S50: The edge-curling limiter 40 moves synchronously with the base material bar 20, so that the surface of the first coating 30 is pressed by the extrusion part 42 on the bottom surface of the edge-curling limiter 40 to form serrations 31.

[0081] In step S10 above, the edge curling limiter 40 can be a sleeve with a bar material channel 41 inside. The bar material channel 41 is arranged axially through the edge curling limiter 40 to accommodate the base material bar 20 and to limit the generation of redundant edge curling at the bottom of the base material bar 20, thereby improving the utilization rate of the base material bar 20 and extending the coating length of a single coating 30.

[0082] In some embodiments, the bar stock channel 41 may include a first channel 411 and a second channel 412. The first channel 411 is located at the lower part of the bar stock channel 41 and is adapted to the outer diameter of the parent bar 20 to restrict the bottom end of the parent bar 20, preventing the plastic deformation flow formed by the softening of the bottom end of the parent bar 20 from rolling upward and forming redundant curls. The second channel 412 is located above the first channel 411, and the inner diameter of the second channel 412 is larger than the outer diameter of the parent bar 20, which can reduce the friction between the rotating parent bar 20 and the inner wall of the curl limiter 40.

[0083] In step S20 above, the base material rod 20 is moved downwards so that it contacts the surface of the substrate 10, preparing for the subsequent coating preparation. A gap is provided between the bottom surface of the edge retainer 40 and the surface of the substrate 10 to facilitate the plastic deformation flow formed by the base material rod 20 to be coated on the surface of the substrate 10 to form a coating.

[0084] In step S30 above, rotating and pressing down the base material rod 20 can cause the base material rod 20 to soften into a plastic deformation flow after thermal deformation caused by friction with the surface of the substrate 10.

[0085] In step S40 above, translating the base material rod 20 along the plane where the substrate 10 is located allows the plastic deformation flow to be coated on the surface of the substrate 10, thus achieving the purpose of coating preparation.

[0086] In step S50 above, the edge curling limiter 40 can be controlled to move synchronously with the base material bar 20, that is, steps S40 and S50 are performed synchronously. In this way, the plastic deformation flow forming the coating can be squeezed and shaped by the extrusion part 42 on the bottom surface of the edge curling limiter 40 in time, so that the coating surface forms a tooth pattern 31. When the next coating is applied to its surface, it can form an interlaced stirring bond, thereby enhancing the bonding force between the coatings.

[0087] It should be noted that during the coating preparation process, the base material rod 20 rotates relative to the substrate 10 while moving along the plane of the substrate 10. The edge curling limiter 40 moves forward with the base material rod 20, but does not rotate with it. To ensure that the depth of the formed serrations 31 is uniform, the edge curling limiter 40 must maintain a constant height relative to the surface of the substrate 10 during the translation process.

[0088] The friction surfacing method for enhancing inter-coating adhesion disclosed in this application can also be applied to solid-state additive manufacturing. The edge-pressing limiter 40 is equivalent to a hollow mixing tool in solid-state additive manufacturing, and an extrusion section 42 is provided on the bottom surface of the hollow mixing tool. During the additive manufacturing process, the master material rod 20 filled in the hollow mixing tool rotates relative to the substrate 10 and moves along the plane of the substrate 10, forming a coating on the surface of the substrate 10, thereby achieving the purpose of additive manufacturing. At the same time, the hollow mixing tool moves forward with the master material rod 20, but does not rotate with the master material rod 20, so that the extrusion section 42 extrudes the coating surface to form teeth 31, thereby enhancing the inter-coating adhesion.

[0089] It should be noted that during the friction welding process, when the base rod 20 rotates and plunges down onto the substrate 10, the tip of the base rod 20 undergoes intense plastic deformation with the substrate 10, generating heat that softens the material at the tip of the base rod 20, forming a plastic deformation flow. As the base rod 20 moves horizontally, the plastic deformation flow forms a strip-shaped coating on the surface of the substrate 10.

[0090] Generally, when the base rod 20 and the substrate 10 are materials with similar melting points, the plastic deformation flow at the tip of the base rod 20 will interact with the substrate 10 to generate friction. When the friction force is greater than the shear strength of the plastic deformation flow of the base rod 20, the plastic deformation flow and the substrate 10 form a metallurgical bond, and part of the plastic deformation flow material adheres to the substrate 10, thereby forming a friction weld overlay coating.

[0091] When the base material 20 is a relatively low melting point alloy (such as aluminum alloy, magnesium alloy or copper alloy) and the substrate 10 is a relatively high melting point alloy (such as steel, titanium alloy, nickel alloy, cobalt alloy or tungsten alloy), the temperature at the tip of the base material 20 when forming a plastic flow under severe plastic deformation is much lower than the surface plastic deformation temperature of the substrate 10. At this time, the friction between the plastic deformation flow and the substrate 10 is very small, and the plastic deformation flow is in a sliding state relative to the substrate 10. It cannot form a metallurgical bond with the substrate 10, and the plastic deformation flow material cannot adhere to the substrate 10, thus failing to form a friction weld coating.

[0092] Please see Figure 17 To address the aforementioned issues, in some embodiments of this application, the method further includes: before moving the parent material rod 20 to contact the surface of the substrate 10, the following steps are taken:

[0093] Step S20′: The surface of the substrate 10 is processed to form a non-planar structure that is metallurgically bonded to the first coating 30. This step can treat the surface of the substrate 10 to increase the friction of the substrate 10 surface, so that the first coating 30 can be better bonded to the substrate 10.

[0094] The surface of the substrate 10 can be processed using any of the following methods: wire cutting, electrical discharge machining, milling, knurling, or rough grinding, to create a non-planar structure. Specifically, the surface of the substrate 10 can be processed into a concave or convex serrated structure, with the depth of the serrations being less than half the thickness of the first coating 30 but greater than 0.1 mm. This avoids the situation where the serration depth is too shallow, failing to increase surface friction, while excessively deep serrations would affect the continuous formation of the friction-welded coating, leading to coating defects or interface defects. By processing the surface of the substrate 10 into a non-planar structure, the frictional force between the plastic deformation flow at the tip of the base rod 20 and the substrate 10 can be increased, allowing the plastic deformation flow to adhere to the substrate 10, thereby forming a well-formed friction-welded coating.

[0095] Please refer to Figure 2 As shown, in some embodiments of this application, the step of the crimping limiter 40 moving synchronously with the parent material bar 20, such that the surface of the first coating 30 is pressed by the pressing portion 42 on the bottom surface of the crimping limiter 40 to form the serrations 31, includes:

[0096] Step S51: Determine the direction of movement of the parent material bar 20;

[0097] Step S52: Adjust the edge curling limiter 40 so that the pressing part 42 on the bottom surface of the edge curling limiter 40 is located on the side opposite to the moving direction of the parent material bar 20.

[0098] Step S53: The edge-curling limiter 40 is translated along the plane where the first coating 30 is located, so that the extrusion part 42 extrudes the surface of the first coating 30 to form the tooth pattern 31.

[0099] The above step S51 can locate the moving direction of the base material bar 20, so as to plan the moving trajectory of the friction surfacing device head.

[0100] Step S52 above can adjust the crimping limiter 40 according to the moving direction of the base material bar 20 to ensure that the extrusion part 42 on the bottom surface of the crimping limiter 40 is located on the side opposite to the moving direction of the base material bar 20. In this way, when the plastic deformation flow is just coated on the surface of the substrate 10, the extrusion part 42 can extrude the coating surface to form the tooth pattern 31.

[0101] It should be noted that the width dimension of the extrusion part 42 should not be less than the width dimension of the coating 30. This ensures that the serrations 31 formed on the surface of the coating 30 can extend to both sides of the coating 30, further improving the bonding force between the coatings.

[0102] In some embodiments of this application, after the crimping limiter 40 moves synchronously with the base material bar 20, causing the surface of the first coating 30 to be pressed by the pressing portion 42 on the bottom surface of the crimping limiter 40 to form serrations 31, the following further steps are included:

[0103] Step S60: Form a second coating 70 on the first coating 30, which is metallurgically bonded to the first coating 30.

[0104] The above step S60 can achieve the purpose of coating thickening by preparing a second coating 70 on the surface of the first coating 30.

[0105] Please refer to Figure 3 In some embodiments of this application, the step of forming a second coating 70 that is metallurgically bonded to the first coating 30 on the first coating 30 includes:

[0106] Step S61: Move the parent material bar 20 and the edge-curling limiter 40 vertically;

[0107] Step S62: Rotate and press down the base material rod 20 to cause the bottom end of the base material rod 20 to undergo severe deformation and soften into plastic deformation flow with the surface of the first coating 30;

[0108] Step S63: The plastic deformation flow is pushed by the rotating parent material rod 20 and forms an interlaced mixing structure with the toothed pattern 31;

[0109] Step S64: Translate the deformed base rod 20 along the plane where the first coating 30 is located to form a second coating 70 on the surface of the first coating 30.

[0110] Step S61 above can move the base material bar 20 and the edge retainer 40 above the first coating 30 to prepare for the preparation of the next coating.

[0111] The above step S62, rotating and pressing down on the base material rod 20, can soften the base material rod 20 into a plastic deformation flow.

[0112] Step S63 above can combine plastic deformation flow with the tooth pattern 31, thereby improving the adhesion between coatings.

[0113] The above step S64 can translate the base material rod 20 along the plane where the first coating 30 is located, so that the plastic deformation flow is applied to the surface of the first coating 30, thereby achieving the purpose of coating thickening.

[0114] Reference Figures 11 to 12 In some embodiments of this application, the extrusion part 42 is a sawtooth structure recessed into the bottom surface of the edge-curling limiter 40, each sawtooth of the extrusion part 42 is a right-angled triangle, and the tooth pattern 31 is a protruding tooth protruding outward from the surface of the first coating 30.

[0115] Please refer to Figure 4 and Figure 13 The steps of the plastic deformation flow being pushed by the rotating parent material rod 20 and forming an interlaced stirring structure with the toothed pattern 31 include:

[0116] Step S631: The base material bar 20 rotates toward the right-angled surface facing the saw teeth;

[0117] Step S632: Under the pushing action of the parent material rod 20, the plastic deformation flow fills the right angle on the outside of the tooth.

[0118] In this embodiment, since the extrusion part 42 is set to be recessed into the bottom surface of the edge-curling limiter 40, the surface of the coating 30 will be extruded by the extrusion part 42 to form a tooth pattern 31 that protrudes from the surface of the coating 30. By setting the right-angled surface of the tooth to face the rotation direction of the base rod 20, the plastic deformation flow generated by the rotation of the base rod 20 can be used to make the plastic deformation flow first contact the right-angled surface of the tooth pattern 31, so as to fill the right angle formed by the right-angled surface of the tooth and the substrate 10 or the previous coating surface, and avoid the formation of gaps at the junction of the upper and lower coatings.

[0119] Please refer to Figures 14 to 15 In some embodiments of this application, the extrusion part 42 protrudes outward from the bottom surface of the edge-curling limiter 40, each tooth of the extrusion part 42 is a right-angled triangle, and the tooth pattern 31 is a groove recessed into the surface of the first coating 30.

[0120] Please refer to Figure 5 and Figure 16 The steps of the plastic deformation flow being pushed by the rotating parent material rod 20 and forming an interlaced stirring structure with the toothed pattern 31 include:

[0121] Step S631′: The base material bar 20 rotates toward the inclined surface facing the saw teeth;

[0122] Step S632′: The plastic deformation flow fills the tooth groove under the pushing action of the parent material rod 20.

[0123] In this embodiment, since the extrusion part 42 is set to protrude outward from the bottom surface of the edge-curling limiter 40, the surface of the coating 30 will be extruded by the extrusion part 42 to form a toothed pattern 31 that is concave to the surface of the coating 30. By setting the inclined surface of the tooth to face the rotation direction of the base rod 20, the plastic deformation flow can be pushed by the rotation of the base rod 20, so that the plastic deformation flow can enter the apex of the toothed pattern 31 along the inclined surface of the toothed pattern 31 to fill the apex of the toothed pattern 31 and avoid the formation of gaps at the junction of the upper and lower coatings.

[0124] In some embodiments of this application, one end of the crimping limiter 40 is connected to the machine head. The step of translating the crimping limiter 40 along the plane where the first coating 30 is located, so that the extrusion part 42 extrudes the surface of the first coating 30 to form the tooth pattern 31, includes:

[0125] Step S531: Control the machine head to drive the edge curling limiter 40 to move synchronously with the base material bar 20, so that the extrusion part 42 on the end face of the edge curling limiter 40 extrudes the surface of the first coating 30 to form teeth 31.

[0126] In the above steps, the die head can drive the edge limiter 40 to move synchronously with the base material bar 20, so that the extrusion section 42 can extrude the coating in time to form serrations 31 on its surface.

[0127] In some embodiments of this application, the parent rod 20 is connected to the rotating spindle by a clamp, and the step of rotating and pressing down the parent rod 20 to cause the bottom end of the parent rod 20 to rub against the substrate 10 and generate thermal deformation includes:

[0128] Step S31: Control the rotating spindle to drive the base material bar 20 to rotate relative to the substrate 10, so that the bottom surface of the base material bar 20 in contact with the substrate 10 generates thermal deformation through friction and forms plastic deformation flow.

[0129] It should be noted that the rotating spindle can be connected to the head of the friction welding device, and the friction welding device also includes a drive component for driving the rotating spindle to rotate. On the one hand, the base material bar 20 can be driven to rotate by the rotating spindle, and on the other hand, the base material bar 20 can be moved in the horizontal or vertical direction under the drive of the head.

[0130] In some embodiments of this application, a cooling step is also included:

[0131] The bottom end of the base material bar 20 is cooled to prevent it from expanding due to heat.

[0132] The intense friction between the base material rod 20 and the substrate 10 or the first coating 30 generates frictional heat, causing the bottom end of the base material rod 20 to expand due to heat. This may cause the base material rod 20 to become stuck in the edge-pressing limiter 40, preventing it from being conveyed downwards smoothly. The above steps can cool the bottom end of the base material rod 20, thereby reducing or preventing the base material rod 20 from expanding and jamming in the edge-pressing limiter 40.

[0133] It should be noted that a cooling device can be used to cool the base material bar 20 in the above steps. The cooling device may include a cooling channel disposed within the edge retainer 40 and a cooling nozzle for spraying cooling medium into the cooling channel. The cooling channel may be arranged around the bottom end of the base material bar 20. By spraying cooling medium into the inlet end of the cooling channel, the cooling medium enters the channel and cools the base material bar 20, and finally exits from the outlet end of the cooling channel, thereby achieving the purpose of cooling the base material bar 20.

[0134] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A friction welding method for enhancing inter-coating adhesion, characterized in that, The method includes the following steps: The edge-pressing limiter (40) is fitted onto the outside of the parent material bar (20); Move the parent material rod (20) to contact the surface of the substrate (10), and set the gap between the bottom surface of the edge retainer (40) and the surface of the substrate (10) according to the coating height; Rotate and press down the base material rod (20) to cause the bottom end of the base material rod (20) to rub against the substrate (10) and generate thermal deformation; The deformed base rod (20) is translated along the plane of the substrate (10) to form a first coating (30). The edge-curling limiter (40) moves synchronously with the base material bar (20), so that the surface of the first coating (30) is pressed by the extrusion part (42) on the bottom surface of the edge-curling limiter (40) to form a tooth (31), the depth of the tooth (31) being less than half the thickness of the first coating (30) but greater than 0.1 mm; Forming a second coating (70) that is metallurgically bonded to the first coating (30) on the first coating (30) includes the following steps: Move the parent material bar (20) and the edge-curling limiter (40) vertically. Rotate and press down the base material rod (20) to cause the bottom end of the base material rod (20) and the surface of the first coating (30) to undergo severe deformation and soften into plastic deformation flow; The plastic deformation flow is pushed by the rotating parent material rod (20) and forms an interlaced stirring structure with the toothed pattern (31); The deformed base rod (20) is translated along the plane where the first coating (30) is located to form a second coating (70) on the surface of the first coating (30). The extrusion part (42) is a sawtooth structure recessed into the bottom surface of the edge-curling limiter (40). Each sawtooth of the extrusion part (42) is a right-angled triangle. The tooth pattern (31) is a convex tooth protruding outward from the surface of the first coating (30). The step of the plastic deformation flow being pushed by the rotating parent material rod (20) and forming an interlaced stirring structure with the teeth (31) includes: The parent material bar (20) rotates toward the right-angled surface facing the saw teeth; The plastic deformation flow fills the right angle on the outer side of the protruding tooth under the pushing action of the parent material rod (20); or The extrusion part (42) is a serrated structure that protrudes outward from the bottom surface of the edge-curling limiter (40). Each serration of the extrusion part (42) is a right-angled triangle. The tooth pattern (31) is a tooth groove that is recessed into the surface of the first coating (30). The step of the plastic deformation flow being pushed by the rotating parent material rod (20) and forming an interlaced stirring structure with the teeth (31) includes: The parent material bar (20) rotates toward the inclined surface facing the saw teeth; The plastic deformation flow fills the tooth groove under the pushing action of the parent material rod (20).

2. The friction welding method for enhancing inter-coating adhesion according to claim 1, characterized in that, At least the lower part of the bar channel (41) of the edge restrictor (40) is adapted to the outer diameter of the parent bar (20) to restrict redundant edge formation at the bottom end of the parent bar (20).

3. The friction welding method for enhancing inter-coating adhesion according to claim 1 or 2, characterized in that, The step of the edge-curling limiter (40) moving synchronously with the base material bar (20) to form a toothed pattern (31) by pressing the surface of the first coating (30) by the pressing part (42) on the bottom surface of the edge-curling limiter (40): Determine the direction of movement of the parent material bar (20); Adjust the edge-pressing limiter (40) so that the pressing part (42) on the bottom surface of the edge-pressing limiter (40) is located on the side opposite to the moving direction of the parent material bar (20); The edge-curling limiter (40) is translated along the plane where the first coating (30) is located, so that the extrusion part (42) extrudes the surface of the first coating (30) to form serrations (31).

4. The friction welding method for enhancing inter-coating adhesion according to claim 3, characterized in that, One end of the edge-curling limiter (40) is connected to the machine head. The step of translating the edge-curling limiter (40) along the plane where the first coating (30) is located, so that the extrusion part (42) extrudes the surface of the first coating (30) to form a tooth pattern (31) includes: The machine head is controlled to drive the edge-curling limiter (40) to move synchronously with the base material bar (20), so that the extrusion part (42) on the bottom surface of the edge-curling limiter (40) extrudes the surface of the first coating (30) to form teeth (31).

5. The friction welding method for enhancing inter-coating adhesion according to claim 4, characterized in that, The base material rod (20) is connected to the rotating spindle by a clamp. The step of rotating and pressing down the base material rod (20) to cause the bottom end of the base material rod (20) to rub against the substrate (10) and generate thermal deformation includes: The rotating spindle is controlled to drive the parent material rod (20) to rotate relative to the substrate (10), so that the bottom surface of the parent material rod (20) in contact with the substrate (10) generates thermal deformation and forms plastic deformation flow through friction.

6. The friction welding method for enhancing inter-coating adhesion according to claim 1 or 2, characterized in that, Also includes: The bottom end of the base material rod (20) is cooled to prevent the bottom end of the base material rod (20) from expanding due to heat.

7. The friction welding method for enhancing inter-coating adhesion according to claim 1 or 2, characterized in that, Before moving the parent material rod (20) to contact the surface of the substrate (10), the following steps are also included: The surface of the substrate (10) is processed to form a non-planar structure on the surface of the substrate (10) for metallurgical bonding with the first coating (30).

8. The friction welding method for enhancing inter-coating adhesion according to claim 7, characterized in that, The surface of the substrate (10) is processed by any one of wire cutting, electrical discharge machining, milling, knurling, or rough grinding.

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