Method for producing a coating

Abstract

The application provides a coating preparation method, and relates to the technical field of friction deposition welding and solid-state additive manufacturing. The preparation method comprises the following steps: forming a first coating on at least one surface of a base material; performing cutting processing on the first coating to form a cutting opening on the first coating; and forming a second coating that is metallurgically combined with the first coating on the base material based on the cutting opening. The application forms the cutting opening on the first coating by performing cutting processing on the first coating, and when the second coating is prepared, the coating material is partially filled in the cutting opening, so that the first coating and the second coating are metallurgically combined at the cutting opening, the non-pore connection between the first coating and the second coating is realized, and the mechanical properties and corrosion resistance of the whole coating are improved.

Description

Technical Field

[0001] This invention relates to the field of solid-state processing technology, and more particularly to a method for preparing a coating. Background Technology

[0002] Friction welding is a process that uses the frictional heat generated by the corresponding movement between a base material and a substrate as a heat source to transfer the base material to the surface of the substrate to form a coating. During friction welding, the base material rotates and comes into contact with the surface of the substrate. The heat generated by the friction between the contact surfaces 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 material and the substrate. Simultaneously, the base material moves linearly in a certain direction, thereby forming a coating on the surface of the substrate.

[0003] Friction stir solid additive manufacturing uses a hollow tool filled with a parent material. The hollow tool drives the parent material to rotate and move horizontally. While rotating, the parent material also moves downward relative to the hollow tool and contacts the substrate surface. After the parent material and the substrate undergo violent deformation due to relative motion, the material softens. The deformation flow is coated onto the substrate surface with the horizontal movement of the hollow tool to form a coating. Under the squeezing action of the hollow tool's shoulder, the coating can be evenly applied to the substrate.

[0004] Existing methods for preparing friction surfacing and friction stir solid additive coatings are limited to single-coat applications because directly preparing the next coating on the side of the previous one can lead to cracks and voids at the junction with the previous coating. Figure 1 As shown, after the first coating 130' is prepared on the substrate 120', the second coating 140' is prepared directly on one side of the first coating 130', resulting in cracks and holes 160' at the junction of the two coatings. This will affect the mechanical properties and corrosion resistance of the coating. Summary of the Invention

[0005] This invention provides a method for preparing a coating to solve the problem of cracks and holes at the joints when preparing multiple coatings in the prior art.

[0006] The technical problem solved by this invention is achieved by the following technical solution:

[0007] A method for preparing a coating, the method comprising the following steps:

[0008] A first coating is formed on at least one surface of the substrate;

[0009] The first coating is machined by cutting to form a cutting edge in the first coating;

[0010] Based on the cutting edge, a second coating is formed on the substrate that is metallurgically bonded to the first coating.

[0011] As a further improvement to the above technical solution:

[0012] The above-described method for preparing a coating further includes, in that, forming a first coating on at least one surface of a substrate, comprising:

[0013] The base material is subjected to heat deformation treatment to obtain deformed base material;

[0014] The base material is pressed down and deformed, and the deformed base material is moved along the plane of the substrate to obtain the first coating.

[0015] The above-mentioned coating preparation method further includes, in which the base material is subjected to heat deformation treatment to obtain a deformed base material, the following steps are taken:

[0016] The base material is brought into contact with the substrate, and the base material is rotated.

[0017] The above-described method for preparing a coating further includes, in which the first coating is machined to form a cutting edge in the first coating, the following steps are taken:

[0018] The edge region of the first coating is machined to form a cutting edge. The edge region includes a first edge region and a second edge region arranged opposite each other, and two third edge regions arranged opposite each other. The third edge regions are connected between the first edge region and the second edge region. The first edge region is located on the advancing side of the first coating, and the advancing side is consistent with the rotation direction of the base material.

[0019] Optionally, the first edge region includes a first separation region separated from the surface of the substrate, the second edge region includes a second separation region separated from the surface of the substrate, and the width of the first separation region is greater than the width of the second separation region.

[0020] The above-described method for preparing a coating further includes, in which the edge region of the first coating is machined to form a cutting edge, the following steps are taken:

[0021] The first edge region and / or the second edge region are machined by cutting to form a cutting edge in the first edge region and / or the second edge region.

[0022] The above-described method for preparing a coating further includes, in which the edge region of the first coating is machined to form a cutting edge, the following steps are taken:

[0023] The third edge region is machined by cutting to form a cutting edge in the third edge region.

[0024] The above-described method for preparing a coating further includes, in which the first coating is machined to form a cutting edge in the first coating, the following steps are taken:

[0025] The surface of the first coating away from the substrate is machined to form a cut on the surface of the first coating.

[0026] In the above-described method for preparing the coating, in the cutting process of the surface of the first coating away from the substrate, the cutting depth D1 and the thickness D2 of the first coating satisfy the following relationship: 0.15≤D1 / D2≤0.25.

[0027] The above-described method for preparing a coating further includes, after machining the surface of the first coating away from the substrate to form a cut on the surface of the first coating, the method further includes:

[0028] A third coating is formed on the surface of the first coating that is away from the substrate.

[0029] In the above-mentioned method for preparing the coating, the cutting process is milling, the milling cutter is a round nose end mill, and the chamfer radius of the round nose end mill is not less than the thickness of the coating;

[0030] And / or, the diameter of the round nose end mill is 0.5mm-1mm smaller than the diameter of the base material of the coating.

[0031] The beneficial effects of this invention are as follows: The coating preparation method provided by this invention has at least the following beneficial effects compared with the prior art: By cutting the first coating, a cutting edge is formed on the first coating. When preparing the second coating, the coating material partially fills the cutting edge, thereby forming a metallurgical bond between the first coating and the second coating at the cutting edge, so as to achieve a non-porous connection between the first coating and the second coating, and improve the overall mechanical properties and corrosion resistance of the coating.

[0032] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0033] 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.

[0034] The invention will now be described in more detail with reference to embodiments and the accompanying drawings.

[0035] Figure 1 This shows a schematic diagram of the structure in the prior art where the first coating and the second coating are laterally connected;

[0036] Figure 2 A schematic flowchart of the coating preparation method provided in the embodiments of the present invention is shown;

[0037] Figure 3 A schematic diagram of friction welding provided in an embodiment of the present invention is shown;

[0038] Figure 4 A schematic diagram of the friction stir solid additive manufacturing provided in an embodiment of the present invention is shown;

[0039] Figure 5 This diagram illustrates a three-dimensional structure for cutting the edge region of the first coating, as provided in an embodiment of the present invention.

[0040] Figure 6 This shows a front view of the cutting of the edge region of the first coating according to an embodiment of the present invention;

[0041] Figure 7 This diagram shows a three-dimensional structure of the first coating and the second coating laterally connected according to an embodiment of the present invention;

[0042] Figure 8 This shows a front view of the lateral connection between the first coating and the second coating provided in an embodiment of the present invention;

[0043] Figure 9 This shows a schematic diagram of the structure in which the first coating and the second coating are laterally connected according to an embodiment of the present invention;

[0044] Figure 10 A schematic diagram of the large-area coating prepared according to an embodiment of the present invention is shown;

[0045] Figure 11 A schematic diagram of a large-area coating prepared according to another embodiment of the present invention is shown;

[0046] Figure 12 This diagram illustrates a three-dimensional structure for cutting the edge region of the first coating according to another embodiment of the present invention.

[0047] Figure 13 This diagram shows a three-dimensional structure of the first and second coatings connected end-to-end according to an embodiment of the present invention.

[0048] In the accompanying drawings, the same parts use the same reference numerals. The drawings are not to scale.

[0049] Figure label:

[0050] 110 - base material, 120, 120′ - substrate, 130, 130′ - first coating, 140, 140′ - second coating, 150 - hollow mixing tool, 160′ - cracks and pores. Detailed Implementation

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] The invention will now be further described with reference to the accompanying drawings.

[0057] This invention provides a method for preparing a coating to solve the problem of cracks and holes at the junction of adjacent coatings when preparing large-area coatings.

[0058] Please see Figure 2 The coating preparation method provided in this embodiment of the invention includes the following steps:

[0059] Step S10: Form a first coating 130 on at least one surface of the substrate 120;

[0060] Step S20: Perform cutting on the first coating 130 to form a cutting edge in the first coating 130;

[0061] Step S30: Based on the cutting edge, a second coating 140 is formed on the substrate 120 that is metallurgically bonded to the first coating 130.

[0062] In some embodiments of this application, the substrate 120 can be a common alloy sheet. In step S10, the first coating 130 can be a base material 110 subjected to heat deformation treatment. The base material 110 can be an alloy material with relatively high performance, such as 7A04 high-strength aluminum alloy, 904 super austenitic stainless steel, 304 austenitic stainless steel, or 718 nickel-based alloy. The heat deformation method can be direct heating or frictional heat generation. Then, the deformed base material 110 is pressed down while moving along the plane of the substrate 120 to obtain the first coating 130.

[0063] In some embodiments of this application, when machining the first coating 130, the machining can be performed on the side of the first coating 130 in the width direction or the end in the length direction, or on the surface of the first coating 130, to form a cutting edge for metallurgical bonding with the subsequent coating. The machining method can be milling, electrical discharge machining, or grinding.

[0064] In some embodiments of this application, when forming a second coating 140 that is metallurgically bonded to the first coating 130 on the substrate 120, the deformed base material 110 is first moved to the side, end, or above where the first coating 130 has a cut, with the base material 110 close to the cut. Then, the deformed base material 110 is moved along the plane of the substrate 120 or the surface of the first coating 130 to form the second coating 140. Since the first coating 130 has a cut, when preparing the second coating 140, the deformed base material 110 partially fills the cut, thereby forming a metallurgical bond between the second coating 140 and the first coating 130 at the cut, achieving a non-porous connection between the first coating 130 and the second coating 140, and improving the overall mechanical properties and corrosion resistance of the coating.

[0065] Specifically, in some embodiments of this application, the base material 110 is subjected to heat deformation treatment to obtain a deformed base material 110, including: contacting the base material 110 with the substrate 120 and rotating the base material 110. Due to the frictional heat generated by the relative movement between the base material 110 and the substrate 120, the base material 110 softens and forms a plastic deformation flow. After moving the base material 110 along the plane where the substrate 120 is located, the base material 110 can be coated on the surface of the substrate 120 to form a first coating 130.

[0066] like Figure 3 The diagram shown is a schematic diagram of a friction surfacing structure provided in an embodiment of the present invention. By contacting the base material 110 with the surface of the substrate 120 and rotating the base material 110, the base material 110 is softened to form a plastic deformation flow, so as to coat the surface of the substrate 120 to form a first coating 130.

[0067] like Figure 4 The diagram shown is a structural schematic of a friction stir solid additive manufacturing system provided in an embodiment of the present invention. The parent material 110 is brought into contact with the surface of the substrate 120, and the parent material 110 is rotated by a hollow stirring tool 150, which softens the parent material 110 to form a plastic deformation flow, so as to coat the surface of the substrate 120 to form a first coating 130.

[0068] Further, step S20: cutting the first coating 130 to form a cutting edge in the first coating 130 includes: cutting the edge region of the first coating 130 to form a cutting edge in the edge region, wherein the edge region includes a first edge region and a second edge region disposed opposite to each other and two third edge regions disposed opposite to each other, the third edge regions being connected between the first edge region and the second edge region, wherein the first edge region is located on the advancing side of the first coating 130, and the advancing side is consistent with the rotation direction of the base material 110.

[0069] Optionally, the first edge region includes a first separation region separated from the surface of the substrate 120, the second edge region includes a second separation region separated from the surface of the substrate 120, and the width of the first separation region is greater than the width of the second separation region.

[0070] Specifically, when the base material 110 rotates, one side of its rotation direction is the forward side, and the other side opposite to the forward side is the rotation side. For example, when the base material 110 rotates clockwise, the forward side is located on the left side of the base material 110. Because the base material 110 exerts a pushing effect on one side of the coating when it rotates, the width of the first separation area located on the forward side is greater than that of the second separation area located on the rotation side.

[0071] like Figure 5 and Figure 6 As shown, cutting the edge region of the first coating 130 to form a cutting edge includes: cutting the first edge region and / or the second edge region to form a cutting edge.

[0072] Specifically, cutting can be performed on the advancing side of the first coating layer 130, or on the rotating side of the first coating layer 130, or both the advancing and rotating sides of the first coating layer 130 can be cut. During cutting, the milling cutter moves along the length of the first coating layer 130, and during the cutting process, the milling cutter needs to be offset inward along the width of the first coating layer 130 to ensure that the first separation area and / or the second separation area are completely milled away.

[0073] like Figures 7 to 11 As shown, when preparing the second coating 140, the advancing side of the second coating 140 is aligned with the cutting edge of the first coating 130. By means of the pushing action of the base material 110 on the advancing side of the coating during rotation, the plastic deformation flow of the advancing side of the second coating 140 and the material of the cutting edge of the first coating 130 undergo relative motion deformation and heat generation, forming a metallurgical bond, thereby achieving a transverse non-porous connection between the coatings.

[0074] In some embodiments of this application, the cutting opening formed in the first edge region and / or the second edge region can be a concave arc shape, and the radius of the cutting opening is not less than 20% of the diameter of the base material 110. For example, when the diameter of the base material 110 is 15mm, the radius of the cutting opening is 3mm. This ensures that the first separation region and / or the second separation region are completely cut, so that the two horizontally adjacent coatings are more completely connected.

[0075] like Figure 12As shown, in some other embodiments of this application, the edge region of the first coating 130 is machined to form a cutting edge, including: machining the third edge region to form a cutting edge.

[0076] Specifically, cutting can be performed at either the starting or ending end of the first coating 130. During cutting, the milling cutter moves to the end of the first coating 130 and cuts an arc-shaped cut with a diameter slightly larger than that of the base material 110 at the end of the first coating 130.

[0077] like Figure 13 As shown, when preparing the second coating 140, the base material 110 is moved to the arc-shaped cutting edge. When the base material 110 is rotated and pressed down, the plastic deformation flow at its end and the material of the arc-shaped cutting edge generate heat through relative motion deformation, forming a metallurgical bond, thereby achieving a pore-free connection between the coatings.

[0078] Furthermore, in this embodiment, the cutting process is milling, and the milling cutter can be a round nose end mill. When cutting the first edge region and / or the second edge region, the chamfer radius of the round nose end mill is not less than the thickness of the coating. This allows the bottom end of the cut to be tangent to the substrate 120. When preparing the second coating 140, it is only necessary to align the edge of the base material 110 with the position where the bottom end of the cut is tangent to the substrate 120 to achieve a lateral non-porous bonding between the coatings.

[0079] When machining the third edge region, the diameter of the round nose end mill is 0.5mm-1mm smaller than the diameter of the base material 110 of the coating. In this way, when preparing the next coating, the base material 110 can be moved into the cutting edge of the previous coating end, so as to achieve a seamless bonding between the coatings.

[0080] In some embodiments, step S20: cutting the first coating 130 to form a cutting edge in the first coating 130 includes: cutting the surface of the first coating 130 away from the substrate 120 to form a cutting edge on the surface of the first coating 130.

[0081] The purpose of machining the surface of the first coating 130 is to level the upper surface of the first coating 130 and clean the oxide layer on the upper surface of the first coating 130 so as to prepare the next coating on the upper surface of the first coating 130.

[0082] Furthermore, during the cutting process on the surface of the first coating 130 that is away from the substrate 120, the cutting depth D1 and the thickness D2 of the first coating 130 satisfy the following relationship: 0.15≤D1 / D2≤0.25.

[0083] In some other embodiments of this application, after machining the surface of the first coating 130 away from the substrate 120 to form a cutting edge on the surface of the first coating 130, the method further includes forming a third coating on the surface of the first coating 130 away from the substrate 12.

[0084] By machining the surface of the first coating 130, the roughness and oxide layer on the surface of the first coating 130 can be removed by milling, thereby enhancing the bonding force between the third coating and the first coating 130 and achieving the purpose of coating thickening.

[0085] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0086] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A method for preparing a coating, characterized in that, include: Forming a first coating on at least one surface of a substrate by friction welding or friction stir solid additive manufacturing includes: contacting a base material with the substrate and rotating the base material to perform thermal deformation treatment on the base material; pressing down the deformed base material and moving the deformed base material along the plane of the substrate to obtain the first coating. The edge region of the first coating is machined to form a cutting edge. The edge region includes a first edge region and a second edge region opposite to each other, and two third edge regions opposite to each other. The third edge regions connect the first edge region and the second edge region. The first edge region is located on the advancing side of the first coating, and the advancing side is aligned with the rotation direction of the base material. The first edge region includes a first separation region separated from the surface of the base material. The second edge region is located on the rotating side of the first coating, and the second edge region includes a second separation region separated from the surface of the base material. The width of the first separation region is greater than the width of the second separation region. The cutting edge is a concave arc shape, and the radius of the cutting edge is not less than 20% of the diameter of the base material. Based on the cutting edge, a second coating is formed on the substrate that is metallurgically bonded to the first coating, comprising: aligning the advancing side of the second coating with the cutting edge of the first coating, and using the pushing action of the base material on the advancing side of the coating during rotation to cause the plastic deformation flow of the advancing side of the second coating to undergo relative motion deformation and heat generation with the material of the cutting edge of the first coating, thereby forming a metallurgical bond.

2. The preparation method according to claim 1, characterized in that, The step of cutting the edge region of the first coating to form a cutting edge includes: The first edge region and / or the second edge region are machined by cutting to form the cutting edge in the first edge region and / or the second edge region.

3. The preparation method according to claim 1, characterized in that, The step of cutting the edge region of the first coating to form a cutting edge includes: The third edge region is machined to form an arc-shaped cutting edge, the diameter of which is slightly larger than the diameter of the base material. In preparing the second coating, the base material is moved to the arc-shaped cutting edge. When the base material is rotated and pressed down, the plastic deformation flow at its end and the material of the arc-shaped cutting edge undergo relative motion deformation and heat generation to form a metallurgical bond.

4. The preparation method according to claim 1, characterized in that, It also includes cutting the surface of the first coating away from the substrate to form a cutting edge on the surface of the first coating away from the substrate, wherein the cutting depth D1 and the thickness D2 of the first coating satisfy the following relationship: 0.15≤D1 / D2≤0.

25.

5. The preparation method according to claim 4, characterized in that, After machining the surface of the first coating away from the substrate to form a cut kerf on the surface of the first coating away from the substrate, the process further includes: A third coating is formed on the surface of the first coating that is away from the substrate.

6. The preparation method according to any one of claims 1 to 5, characterized in that, The cutting process is milling, the milling cutter is a round nose end mill, the chamfer radius of the round nose end mill is not less than the thickness of the first coating; and / or, the diameter of the round nose end mill is 0.5mm-1mm smaller than the diameter of the base material.

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