Bionic dentate interlaced interlocking structure coating as well as preparation method and application of bionic dentate interlaced interlocking structure coating

Abstract

The invention discloses a bionic dentate interlaced interlocking structure coating and a preparation method and application thereof.The preparation method comprises the steps that a transition layer of a Cu-based protruding wedge-shaped array is prepared on a base body through a laser cladding method, then the base body with the transition layer is rotated by 90 degrees, titanium-based alloy powder is clad on the surface of the base body, and then the base body with the transition layer is obtained; and finally, an interlocking structure coating of an interlocking structure among the Ti-based material surface layer, the Cu-based protruding wedge-shaped array and the base body is formed. Due to the existence of the protruding wedge-shaped microarray, the Cu surface and the Fe surface appear in a staggered mode, reflection of Cu alloy to laser is reduced, and the Ti-based composite coating can be normally cladded. Besides, due to the existence of the protruding wedge-shaped microarrays, part of coating interfaces are changed into Ti / Cu interfaces and Fe / Cu interfaces, and formation of Ti / Fe intermetallic compounds is reduced, so that the coating bonding strength is improved, and the service life of the maritime work steel and the stainless steel in the severe environment and the complex load bearing environment is prolonged.

Description

Technical Field

[0001] The present invention belongs to the field of material surface strengthening and additive manufacturing. Specifically, it discloses a preparation technology for a bionic interlocking structure coating with jagged teeth, mainly aiming at key components with harsh service environments and complex loads, such as hydraulic columns, drill pipes, and icebreaker propellers on offshore platforms, marine engineering equipment, and ships. Background Art

[0002] In a corrosive marine environment, almost all types of steel are easily corroded, and corrosion damage is one of the main failure forms of marine engineering steel. Key components such as hydraulic columns, drill pipes, and icebreaker propellers on offshore platforms, marine engineering equipment, and ships not only suffer from corrosion damage but also are subjected to complex working conditions such as high-speed wear and ice load impact. Currently, the materials widely used for key components are marine engineering steel and stainless steel, and their wear and corrosion resistance cannot meet the requirements of complex and harsh environments. Therefore, obtaining corrosion-resistant, wear-resistant, and impact-resistant coatings on the surfaces of these key components through cladding and additive manufacturing has become an important development trend to extend the service life and reduce costs. Currently, the service environments of key components are harsh, and they need to withstand lateral / longitudinal loads such as impact and wear. The bonding strength between the coating and the substrate is one of the key indicators to ensure the long-term service of key components. Therefore, it is necessary to improve the bonding strength between the coating and the substrate.

[0003] Chinese Patent Application Publication No. CN119020781A discloses a wear-resistant and corrosion-resistant stainless steel amorphous composite coating material and its preparation method. This method has high precision in composition control, strong process stability and repeatability, and can achieve excellent wear-resistant and corrosion-resistant properties of stainless steel coating materials. Chinese Patent Application Publication No. CN118291973A discloses a copper-containing antibacterial martensitic stainless steel coating and its preparation. The surface hardness of the copper-containing antibacterial martensitic stainless steel coating obtained by this technology is 500 - 525HV, the corrosion potential ≥ -0.21V, and the corrosion current ≤ 0.77×10 -5 A·cm -2, the sterilization rate of Staphylococcus aureus is ≥92%. Chinese patent publication number CN118531390A discloses a laser preparation method for a wear-resistant and corrosion-resistant strengthening layer of a guide rod, which improves the wear and corrosion resistance of the coating by adding WC to stainless steel. Chinese patent application publication number CN108165982 A discloses a method for preparing a nickel-based wear-resistant and corrosion-resistant coating on a sucker rod substrate using ultra-high-speed laser cladding technology. The coating has no defects such as pores and cracks, which improves the corrosion resistance of the sucker rod. Chinese patent application publication number CN108118334A discloses a method for preparing a cobalt-based wear-resistant and corrosion-resistant coating on a nuclear power seawater pump shaft using ultra-high-speed laser cladding technology. The prepared coating has no obvious defects and can improve the wear and corrosion resistance of the seawater pump shaft. However, the coatings in the above patents, whether stainless steel coatings or Co-based / Ni-based coatings, have inferior corrosion resistance to Ti-based coatings. No matter how they are regulated, they are limited by the properties of their own materials and it is difficult to significantly improve their corrosion resistance and wear resistance. Therefore, developing Ti-based composite coatings on the surface of marine steel or stainless steel is a new development direction to further improve the wear and corrosion resistance of key components of marine equipment.

[0004] However, there are two main problems in preparing Ti-based composite coatings on the surface of offshore steel and stainless steel: first, the thermal physical properties of the substrate and the Ti-based composite coating are quite different, resulting in large thermal stress during cladding; second, brittle Ti-Fe intermetallic compounds will be generated at the interface between the two. Especially when multiple passes are clad, the repeated thermal cycles of the cladding process will make the thermal stress greater and more Ti-Fe intermetallic compounds will be generated, which will eventually lead to direct peeling of the Ti-based composite coating prepared on the surface of offshore steel or stainless steel (such as Figure 2 ), making the coating unusable. Currently, there are two ways to solve this problem. One is to try to reduce heat input and thermal cycle. By optimizing the laser process, TC4 coating can be prepared on the stainless steel surface. However, the bonding strength between the TC4 coating and the substrate is only 40-70MPa. At the same time, the range of process parameters is also very narrow. Only simple TC4 powder can be clad, and it is difficult to prepare complex Ti composite coatings. Another method is to add a transition layer. The technology related to the present invention is to add a transition layer.

[0005] At present, the method of adding a transition layer is widely used in the welding field. The transition layer powders used in the prior art include Ag, Ta, Co, Mo, W, Cu, etc. Among them, Cu is suitable for the cladding field that requires a large-area transition layer due to its relatively low price. At present, using Cu as a transition layer in the plasma cladding field has been realized. For example, a method for preparing a titanium alloy coating on the surface of a steel substrate disclosed in Chinese Patent Application Publication No. CN111607755A. This is because plasma cladding is not sensitive to Cu, a highly reflective material, and not much energy will be reflected. However, due to the relatively large heat input of plasma cladding, the energy is not concentrated enough, the heat affected zone of the substrate is relatively deep, and the cladding efficiency is low. In addition, the dilution rate of plasma cladding is relatively high, and a large amount of Cu and Fe will be reversed into the surface material during the cladding process, which will greatly reduce the corrosion resistance of the titanium alloy and fail to achieve the ideal effect. Currently, this process has been gradually replaced by laser. However, in the laser cladding field, if the Cu alloy is completely used as a transition layer, new problems will occur when the Ti-based alloy is cladded on the surface of the Cu alloy. As a highly reflective material, Cu has a high reflectivity to laser, which greatly reduces the power density of the laser, making it impossible to melt the Ti alloy and difficult to form a cladding layer. For example, a method for preparing a titanium alloy coating on the surface of a steel substrate disclosed in Chinese Patent Application Publication No. CN119433534A. In order to make the obtained titanium alloy coating completely fuse with the substrate body, a tin bronze powder containing precious metal tin is used as the transition layer powder. The steel substrate is preheated in advance, the tin bronze powder is evenly coated on the surface of the steel substrate with a binder, a copper transition layer is prepared on the surface of the steel substrate by laser cladding, and then the surface of the cladding layer is polished flat by mechanical processing; the titanium alloy powder is evenly coated on the surface of the transition layer with a binder; finally, a titanium alloy coating is prepared on the surface of the steel substrate by laser cladding. This technology uses a powder laying process, with poor forming and complex process. Moreover, the introduction of precious metal tin results in high cost. The method of improving the coating performance by increasing cost and process complexity is not conducive to industrialization. Summary of the Invention

[0006] In order to improve the wear and corrosion resistance and service life of key components of marine engineering equipment, expand the process window for laser cladding of Ti-based composite coatings on the surfaces of marine steel and stainless steel, improve the bonding strength between the coating and the substrate, and provide a new way for laser cladding of Ti-based composite coatings on the surfaces of marine steel and stainless steel, the present invention provides a bionic interlocking structure coating with jagged teeth.

[0007] The present invention also provides a preparation method and application of this bionic interlocking structure coating with jagged teeth.

[0008] To achieve the above object, the technical solution adopted by the present invention is:

[0009] A bionic interlocking structure coating with jagged teeth, characterized in that a transition layer of a Cu-based protruding wedge array is first prepared on a substrate by laser cladding, then the substrate with the transition layer is rotated 90°, and then a titanium-based alloy powder is cladded on its surface, finally forming an interlocking structure coating with a jagged teeth interlocking structure among the Ti-based material surface layer, the Cu-based protruding wedge array and the substrate; the Cu-based protruding wedge array refers to a microarray composed of single protruding lines or single protruding points similar to wedges of copper on the substrate, where the "micro" refers to the millimeter level.

[0010] Furthermore, the shape of the Cu-based protruding wedge array includes at least zigzag, straight, fishbone and dot matrix.

[0011] The method for preparing the above-mentioned bionic interlocking structure coating with jagged teeth provided by the present invention is carried out according to the following steps.

[0012] Step 1: Configuration of raw material powder

[0013] The raw material powder includes copper alloy powder and titanium-based alloy powder. The titanium-based alloy powder is mainly composed of TC4 powder and ceramic phase. The powders constituting the titanium-based alloy powder are mixed by a ball mill.

[0014] Step 2: Laser cladding of the transition layer

[0015] First, the surface of the offshore steel or stainless steel is pretreated to remove oil stains and rust. The cladding of different-shaped Cu-based protruding wedge arrays is carried out on the pretreated surface of the offshore steel or stainless steel according to a pre-designed program. The cladding process parameters are: the spot diameter is 3 mm, the cladding laser power is 1400 W - 2400 W, the cladding speed is 6 mm / s - 12 mm / s, the powder feeding speed is 0.1 kg / h - 0.3 kg / h, and the single-pass cladding spacing / dot matrix spacing is 2 - 10 mm.

[0016] Step 3: Laser cladding of titanium-based alloy powder

[0017] The substrate with the Cu-based protruding wedge array is rotated 90°, and TC4 alloy powder is cladded on its surface. The spot diameter is 3 mm, the cladding laser power is 1400 W - 2400 W, the cladding speed is 6 mm / s - 12 mm / s, the powder feeding speed is 0.2 kg / h - 0.8 kg / h, and the single-pass cladding spacing is 1 - 1.5 mm.

[0018] Furthermore, in step 1, the ceramic phase includes various powders such as carbides, nitrides, borides and oxides. Further; the ceramic phase is preferably BN or B4C. When the ceramic phase is BN, the mass ratio of TC4 to BN is 98:2; when the ceramic phase is B4C, the mass ratio of TC4 to B4C is 96:4.

[0019] Furthermore, in Step 1, the particle size of the TC4 powder is 53μm - 78μm; the particle size of the ceramic phase is 10nm - 10μm; the particle size of the Cu alloy powder is 53μm - 78μm.

[0020] Furthermore, in Step 3, when the shape of the Cu-based protruding wedge array is dot-shaped, the laser residence time is 0.5s.

[0021] The coating prepared by the present invention is mainly used for key components such as hydraulic columns, drill pipes, and icebreaker propellers on offshore platforms, marine engineering equipment, and ships.

[0022] The advantages of the present invention are:

[0023] 1. The present invention proposes to construct a Cu-based protruding wedge array on the surface of marine steel or stainless steel, which can cleverly avoid laser cladding on a large area of the Cu surface. The existence of the protruding wedge microarray makes the Cu surface and the Fe surface appear alternately, reducing the reflection of the laser by the Cu alloy and enabling the normal cladding of the Ti-based composite coating. In addition, the existence of the protruding wedge microarray makes part of the coating interface become the Ti / Cu interface and the Fe / Cu interface, reducing the formation of Ti / Fe intermetallic compounds, thereby improving the coating bonding strength. The micro-protrusions of Cu form a bionic interlocking structure with the Ti-based coating, and this structure can increase the mechanical bonding strength between the coating and the substrate. The composite coating prepared by the present invention has a thickness of 2 - 10mm and a hardness of 400 - 800HV. 0.2 , and the wear resistance is about 2 - 20 times that of marine steel and stainless steel, and the corrosion resistance is much better than that of marine steel and stainless steel.

[0024] 2. The method for preparing a Ti-based composite coating on the surface of marine steel and stainless steel by using the bionic interlocking structure proposed by the present invention. The existence of the prepared bionic interlocking structure plays the roles of mechanical occlusion and metallurgical bonding at the same time, reducing the generation of thermal stress, reducing the direct contact between Ti and Fe, and avoiding the formation of more Ti-Fe intermetallic compounds, thereby greatly improving the bonding force between the Ti-based coating and the marine steel and stainless steel substrates, providing the possibility for the application of Ti-based composite coatings on the surface of marine steel and stainless steel. At the same time, this method is not sensitive to process parameters, has a large process parameter window, can use a relatively high power for cladding to prepare Ti-based powders containing various carbides, nitrides, borides, and oxides, and can achieve the simultaneous improvement of the wear resistance and corrosion resistance of the Ti composite coating, and extend the service life of marine steel and stainless steel in environments with harsh conditions and complex loads.

[0025] 3. The present invention designs a bionic interlocking transition layer with jagged teeth on the surface of offshore steel and stainless steel, and then prepares the outermost Ti-based composite coating on the surface of the transition layer. The design of this structural method improves the bonding strength between the Ti-based coating and the offshore steel and stainless steel substrates, and at the same time can broaden the process parameter window for preparing the Ti coating, enabling the outermost Ti-based powder to be flexibly designed according to the actual working conditions. The outermost Ti-based powder materials mainly consist of TC4 powder, BN, B4C, and various powders such as carbides, nitrides, borides, and oxides, which can be configured according to specific corrosion and wear resistance requirements. Among them, the mixture of TC4 powder and BN or B4C can in-situ obtain TiB2 and TiN ceramic phases, which can greatly improve the wear resistance of the composite coating and is suitable for severe high-speed wear conditions. The composite coating prepared by the bionic interlocking structure coating and method can greatly improve the wear and corrosion resistance of offshore steel and stainless steel, and improve its service life in environments with harsh conditions and complex loads. Description of the Drawings

[0026] Figure 1 is a schematic diagram of the bionic interlocking structure with jagged teeth proposed by the present invention. Figure 1 (a), Figure 1 (b), Figure 1 (c), Figure 1 (d) successively show that the shapes of the Cu-based protruding wedge arrays are zigzag, linear, fishbone-shaped, and dot-shaped.

[0027] Figure 2 is a physical diagram of directly cladding the Ti-based composite coating on the stainless steel surface.

[0028] Figure 3 is a physical diagram of the cladding effect of Example 1 of the present invention.

[0029] Figure 4 is a scanning schematic diagram of the cladding layer interface prepared in Example 1 of the present invention, where Figure 4 (a) is a scanning schematic diagram of the interface junction perpendicular to the cladding direction of the titanium base layer, and 4(b) is a scanning schematic diagram of the interface junction along the cladding direction of the titanium base layer.

[0030] Figure 5 is a performance test curve graph of the TC4 + 2BN coating prepared in Example 1 of the present invention, where Figure 5 (a) shows the bonding strength test graph of the bionic interlocking structure coating of the present invention and the substrate; Figure 5 (b), 5(c), Figure 5 (d) successively show the electrochemical comparison schematic diagram, hardness comparison schematic diagram, and wear rate comparison schematic diagram of offshore steel, stainless steel, and the composite coating of the present invention.

[0031] Figure 6 is a physical diagram of the cladding effect of Example 2 of the present invention.

[0032] Figure 7 is a scanning schematic diagram of the interface of the cladding layer prepared in the second embodiment of the present invention, where Figure 7 (a) is a scanning schematic diagram of the interface joint perpendicular to the cladding direction of the titanium base layer, and 7(b) is a scanning schematic diagram of the interface joint along the cladding direction of the titanium base layer.

[0033] Figure 8 is a performance test curve graph of the TC4 + 4B4C coating prepared in the second embodiment of the present invention, where Figure 8 (a) shows the test graph of the bonding strength between the bionic interlocking structure coating of the present invention and the substrate; Figure 8 (b), 8(c), Figure 8 (d) successively shows the electrochemical comparison schematic diagram, hardness comparison schematic diagram, and wear rate comparison schematic diagram of the marine steel, stainless steel, and the composite coating of the present invention. Specific Embodiments

[0034] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0035] Figure 1 is a schematic diagram of the bionic interlocking structure with canine teeth interlaced proposed by the present invention. It can be seen from the figure that due to the existence of the Cu-based protruding wedge-shaped array, the Cu surface and the Fe surface appear alternately at the coating interface. At the same time, part of the coating interface becomes the Ti / Cu interface and the Fe / Cu interface, so that the finally formed coating realizes the interlock among the Ti-based material surface layer, the Cu-based protruding wedge-shaped array, and the substrate.

[0036] The specific preparation method and performance characterization of the present invention will be described in detail below through two embodiments.

[0037] Embodiment 1: Taking the linear Cu-based protruding wedge-shaped array as an example, the preparation method is as follows:

[0038] Step 1: Powder configuration

[0039] The TC4 powder and BN powder are uniformly mixed by a ball mill according to the mass ratio of 98:2. The particle size of TC4 is 53μm - 78μm, and the particle size of BN is 20nm. The mixed powder and the Cu alloy powder (53μm - 78μm) are respectively placed in an oven, and the temperature is set at 120°C and dried for 2 hours. The main components of the TC4 alloy powder used in the present invention are: Ti: 90wt%; Al: 6wt%; V: 4wt%; The main components of the Cu alloy powder are: Cu: 86wt%; Al: 9.5wt%; Fe: 4.5wt%.

[0040] Step 2: Laser cladding transition layer

[0041] Use pulsed laser to remove oil stains and rust on the surface of the offshore steel;

[0042] On the surface of the treated offshore steel, carry out the cladding of the Cu-based protruding wedge array according to the designed program. The spot diameter is 3 mm, the cladding laser power is 2000 W, the single-pass cladding spacing is 4 mm, the cladding speed is 8 mm / s, and the powder feeding speed is 0.3 kg / h to obtain a linear Cu-based protruding wedge array;

[0043] Step 3: Laser cladding titanium-based alloy powder layer TC4 + 2BN

[0044] Rotate the offshore steel with the Cu-based protruding wedge array by 90°, and finally obtain a jagged interlocking structure coating about 3 mm thick by cladding TC4 alloy powder on its surface; the laser cladding parameters are: the spot diameter is 3 mm, the cladding laser power is 2000 W, the single-pass cladding spacing is 1.5 mm, the cladding speed is 8 mm / s, and the powder feeding speed is 0.6 kg / h. (The cladding effect is as shown in Figure 3 ).

[0045] Example 2: Take the fishbone-shaped Cu-based protruding wedge array as an example. The preparation method of Example 2 is basically the same as that of Example 1, except that:

[0046] In Step 1, use TC4 powder and B4C as the titanium-based powder, and the two are mixed in a mass ratio of 96:4; in Step 2, the single-pass cladding fish main bone spacing is 10 mm, and the single-pass cladding fish branch bone spacing is 2 mm to obtain a fishbone-shaped Cu-based protruding wedge array; in Step 3, the cladding laser power is changed to 2400 W, the cladding speed is changed to 6 mm / s, and the powder feeding speed is changed to 0.8 kg / h to finally obtain a jagged interlocking structure coating TC4 + 4B4C about 2 mm thick. The physical object of the cladding effect of Example 2 is shown in Figure 6 .

[0047] Test the coating properties obtained in Example 1 and Example 2 respectively. The test process is as follows:

[0048] Use a scanning electron microscope to observe the interface of the coating prepared in the example to judge whether there is good interface bonding. The scanning results are shown in 4(a)-4(b) (Example 1) and 7(a)-7(b) (Example 2) respectively. It can be seen from the figures that both the coating and the substrate show good interface bonding. The thickness of the coating in Example 1 can reach 3 mm, and the thickness of the coating in Example 2 is about 2 mm; from Figure 4 and Figure 7It can also be seen that the presence of the Cu-based protruding wedge arrays changes some of the coating interfaces into Ti / Cu interfaces and Fe / Cu interfaces, reducing the formation of Ti / Fe intermetallic compounds and increasing the coating bonding strength.

[0049] The shear strength was tested to evaluate the bonding strength between the coatings and the substrates in Example 1 and Example 2. The test results are shown in Figure 5 (a) and 8(a), respectively. The test results show that the bonding strength between the bionic interlocking structure coating and the substrate in Example 1 of the present invention is 159.8 MPa, and that in Example 2 is 217.1 MPa, which are much greater than the 50 - 60 MPa of Ti / Fe bonding.

[0050] An electrochemical workstation (Gamry 3000) was used to conduct the corrosion evaluation experiment. The electrolyte was selected as 3.5 wt.% NaCl solution, the reference electrode was selected as Ag / AgCl electrode, and the counter electrode was selected as a platinum wire electrode. The potentiodynamic polarization curve started from -0.3 V OCP to 1.0 V Ag / AgCl, and the scanning rate was 0.5 mV / s. The test results of Example 1 and Example 2 are shown in Figure 5 (b) and 8(b), respectively. The results show that the corrosion resistance of the composite coatings of the present invention is much higher than that of offshore steel and stainless steel.

[0051] A hardness tester was used to test the hardness of the composite coatings. The test force was 200 g, and the continuous loading time was 10 s. The test results of Example 1 and Example 2 are shown in Figure 5 (c) and 8(c), respectively. The results show that the hardness of the composite coating in Example 1 reaches 600 ± 20 HV 0.2 , and the hardness of the composite coating in Example 2 reaches 800 ± 20 HV 0.2 , both of which are much greater than the hardness of offshore steel and stainless steel.

[0052] An Rtec friction and wear tester was used to evaluate the wear resistance of the substrates and coatings. The force was 30 N, the wear time was 30 N, the friction mode was reciprocating, the frequency was 1 HZ, and a 3D profiler was used to calculate the volume of the wear scars. The test results of Example 1 and Example 2 are shown in Figure 5 (d) and 8(d), respectively. The results show that the wear rate of the composite coating (TC4 + 2BN) in Example 1 can reach 1.1 ± 0.23×10 -8 mm 3 / (mm·N), and the wear resistance is increased by about 2 times that of offshore steel and 10 times that of stainless steel; the wear rate of the composite coating (TC4 + 4B4C) in Example 2 can reach 5.0 ± 0.23×10 -9 mm 3 / (mm·N), and the wear resistance is increased by about 4 times that of offshore steel and 20 times that of stainless steel.

[0053] Figure 2 This is a physical picture of directly preparing a Ti-based composite coating on a stainless steel surface. As can be seen from the figure, the prepared Ti-based composite coating is directly peeled off and cannot be used, which also indirectly reflects the feasibility and necessity of the preparation process of the present invention.

[0054] It should be noted that the present invention mainly protects the bionic coating with a similar interlocking structure of a tooth-like structure prepared on stainless steel or marine engineering steel by laser cladding and controlling process parameters. The ratio of each component in the titanium-based alloy, the selection of ceramic phases and the powder size involved are not the focus of the present invention. In practice, those skilled in the art can modify the ratio of each component according to the coating performance requirements. For example, if the coating is required to have outstanding wear resistance, more ceramic particles can be added. If the coating is required to have outstanding corrosion resistance, less ceramic phases can be added. This is not difficult for those skilled in the art to do. In addition, the above is only an embodiment of the present invention and is not intended to limit the present invention, but the protection scope of the present invention is not limited to this. Any changes or substitutions that are not conceived through creative labor should be covered within the protection scope of the present invention. The specific protection scope shall be subject to the records in the claims.

Claims

1. A bionic interlocking structure coating with jagged teeth, characterized in that, First, a transition layer of Cu-based protruding wedge arrays is prepared on the substrate by laser cladding. Then, the substrate with the transition layer is rotated 90°. Next, a titanium-based alloy powder is cladded on its surface. Finally, an interlocking structure coating with a jagged interlocking structure among the Ti-based material surface layer, the Cu-based protruding wedge arrays, and the substrate is formed. The Cu-based protruding wedge arrays refer to minute arrays composed of individual protruding wire or individual protruding points similar to wedges on the substrate, where "minute" refers to the millimeter level.

2. The bionic interlocking structure coating with jagged teeth as described in claim 1, wherein The shapes of the Cu-based protruding wedge arrays at least include polyline type, straight line type, fishbone type, and dot matrix type.

3. A preparation method of a bionic interlocking structure coating with jagged teeth as described in claim 1 or 2, characterized in that, It is carried out according to the following steps. Step 1: Configuration of raw material powders The raw material powders include copper alloy powders and titanium-based alloy powders. The titanium-based alloy powder mainly consists of TC4 powder and ceramic phase. The powders constituting the titanium-based alloy powder are mixed by a ball mill. Step 2: Laser cladding of the transition layer First, the surface of the offshore steel or stainless steel is pretreated to remove oil stains and rust. Then, on the pretreated surface of the offshore steel or stainless steel, the cladding of Cu-based protruding wedge arrays with different shapes is carried out according to a pre-designed program. The cladding process parameters are: the spot diameter is 3 mm, the cladding laser power is 1400 W - 2400 W, the cladding speed is 6 mm / s - 12 mm / s, the powder feeding speed is 0.1 kg / h - 0.3 kg / h, and the single-pass cladding spacing / dot matrix spacing is 2 - 10 mm. Step 3: Laser cladding of the titanium-based alloy powder The substrate with the Cu-based protruding wedge arrays is rotated 90°, and TC4 alloy powder is cladded on its surface. The spot diameter is 3 mm, the cladding laser power is 1400 W - 2400 W, the cladding speed is 6 mm / s - 12 mm / s, the powder feeding speed is 0.2 kg / h - 0.8 kg / h, and the single-pass cladding spacing is 1 - 1.5 mm.

4. The preparation method of the bionic interlocking structure coating with jagged teeth as described in claim 3, characterized in that, In Step 1, the ceramic phase includes various powders such as carbides, nitrides, borides, and oxides.

5. The preparation method of the bionic interlocking structure coating with jagged teeth as described in claim 4, characterized in that, The ceramic phase is BN or B4C.

6. The preparation method of the bionic interlocking structure coating with jagged teeth as described in claim 1, characterized in that, When the ceramic phase is BN, the mass ratio of TC4 to BN is 98:2; when the ceramic phase is B4C, the mass ratio of TC4 to B4C is 96:

4.

7. The preparation method of the bionic interlocking structure coating with jagged teeth as described in claim 3, characterized in that, In Step 1, the particle size of the TC4 powder is 53 μm - 78 μm; the particle size of the ceramic phase is 10 nm - 10 μm; the particle size of the Cu alloy powder is 53 μm - 78 μm.

8. The preparation method of the bionic interlocking structure coating with jagged teeth as described in claim 3, characterized in that, In Step 3, when the shape of the Cu-based protruding wedge arrays is dot matrix type, the laser residence time is 0.5 s.

9. Application of a bionic jagged interlocking structure coating as described in Claim 1 in key components such as hydraulic columns, drill pipes, and icebreaker propellers of offshore platforms, offshore equipment, and ships.

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