Method for preparing superhard wear-resistant coating by supersonic electric arc spraying technology and application

Abstract

This invention belongs to the field of high-hardness wear-resistant coating technology, and discloses a method and application for preparing a titanium nitride / titanium oxide ultra-hard wear-resistant coating using supersonic arc spraying technology. The high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating is TiN-TiO2-TiN. 0.3 This composite ceramic coating features adjustable thickness and microstructure, enabling the uniform, layered distribution of titanium nitrides and oxides, with the proportion of ultra-hard titanium nitrides exceeding 80%. Using readily available pure titanium wire as raw material, and employing supersonic arc spraying technology, the coating achieves wear-resistant and corrosion-resistant ceramic composite coatings on the surfaces of commonly used structural steel and aluminum alloy engineering equipment and materials through precise adjustment of spraying parameters. The coating preparation method is simple, with no stringent requirements for the construction and processing environment, and boasts high preparation efficiency. This coating can be used for surface protection of various workpieces and engineering structures in marine environments and areas with severe wear conditions near the sea.

Description

Technical Field

[0001] This invention belongs to the field of high-hardness wear-resistant coating technology, and specifically relates to a method and application for preparing titanium nitride / titanium dioxide superhard wear-resistant coatings using supersonic arc spraying technology. Background Technology

[0002] TiN 0.3 TiN belongs to group IV transition metal nitrides and has a mixed structure of metallic and covalent bonds, resulting in characteristics of both metallic and covalent crystals. It exhibits excellent properties in wear resistance, corrosion resistance, and electrical properties. It has been widely used in cutting tools, wear-resistant coatings for engineering equipment, marine engineering, and electronic components.

[0003] TiO2 has high hardness, good corrosion resistance, and special electrical properties, making it widely used in corrosion-resistant and wear-resistant coatings, semiconductor industry, and coating industry.

[0004] In the complex marine environment, engineering equipment and components are not only corroded by corrosive ions in seawater, but also subjected to erosion damage due to seawater movement, floating debris, and the movement of fish and microorganisms. Wear is even more severe on near-shore engineering equipment surfaces in tidal zones or where there is contact wear between friction pairs. The mechanical properties of worn and corroded areas deteriorate, and numerous easily diffused defects appear on the surface, leading to a rapid decline in performance and premature failure.

[0005] Supersonic arc spraying, as a type of thermal spraying, boasts advantages such as a simple spraying process, strong adaptability to various operating conditions, low cost, and flexible preparation of spraying filaments. It is widely used in the preparation of wear-resistant and corrosion-resistant functional coatings. However, the principle of arc spraying dictates that the spraying filament can only be composed of conductive metal wires. This makes it impossible to directly deposit ceramic composite coatings from ceramic raw materials. The emergence of powder-cored spraying filaments has solved this problem, allowing pre-designed mixed powders to be encapsulated within conductive metal tubes, thus diversifying the raw materials used in spraying. However, the melting point, particle size, dispersibility, and oxidation characteristics of ceramic particles significantly affect the coating performance. Incomplete melting of powder particles during spraying, poor atomization, and incomplete dispersion of droplets in the substrate all lead to excessive defects in the coating, thereby affecting the phase properties of the coating. Therefore, controlling the spraying parameters and relying on the mutual reactions of atomized metal particles during the spraying process to obtain corresponding high-performance ceramic coatings has become an important research direction. The behavior of high-speed, high-temperature molten metal droplets in air is an extremely complex and difficult-to-control process. Different spraying conditions will result in very different coating products. Summary of the Invention

[0006] To overcome the shortcomings and deficiencies of the prior art, the primary objective of this invention is to provide a high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating. This coating uses readily available pure titanium wire as raw material and employs supersonic arc spraying technology. By precisely adjusting the spraying parameters, a wear-resistant and corrosion-resistant ceramic composite coating is prepared on the surface of commonly used structural steel and aluminum alloy engineering equipment and materials.

[0007] Another objective of this invention is to provide a method for preparing the above-mentioned high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating.

[0008] Another object of the present invention is to provide the application of the above-mentioned high-hardness, wear-resistant and corrosion-resistant composite ceramic coating.

[0009] The objective of this invention is achieved through the following solution:

[0010] A high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating is prepared by supersonic arc spraying of pure titanium wire. The high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating is TiN-TiO. 2- TiN 0.3 Composite ceramic coating.

[0011] Preferably, the high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating is mainly composed of titanium nitrides and titanium oxides, with the total proportion of ultra-hard phase titanium nitrides exceeding 80%.

[0012] Preferably, the main components of the high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating are TiN, TiO2, and TiN. 0.3 .

[0013] The thickness of the high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating is 150-500μm.

[0014] The purity of the titanium wire is preferably ≥99.9%.

[0015] The diameter of the titanium wire is 1.0-2.0 mm, preferably 2.0 mm.

[0016] The length of the titanium wire is ≥1500mm.

[0017] The parameters of the supersonic arc spraying process are as follows: arc operating voltage 30-42V, arc operating current ≤150A, wire feeding speed 5m / min-9m / min, compressed air pressure ≥0.8Mpa, and spraying distance 120-180mm. The servo motor controlling the spray gun movement has a speed of 5-20mm / s horizontally and 5-15mm / s vertically. Depending on the wire feeding voltage and speed, the optimal spraying time per pass is 5-10s to prevent thermal stress cracking of the coating due to excessive spraying time. The aforementioned metal wire melts under a high-temperature arc, is accelerated by high-pressure gas to form supersonic atomized droplets, and then impacts, diffuses, spreads, and rapidly solidifies on the substrate to form a dense, defect-free, strongly bonded, and high-hardness functional coating with certain corrosion resistance and electronic properties.

[0018] A method for preparing the aforementioned high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating includes the following steps: fixing pure titanium wire using a roller feeding device, setting the spraying parameters on a control panel, and then spraying to obtain the high-hardness, wear-resistant, and corrosion-resistant ceramic coating. This preparation method allows for precise control of the coating thickness and ceramic products. The spraying method is simple and highly adaptable, making it a relatively efficient and low-cost coating preparation method.

[0019] Currently, a large number of equipment operating in marine environments, such as ships, offshore drilling platforms, cross-sea bridges, and oil and gas pipelines, are generally constructed using cast iron, structural steel, and aluminum alloys. Especially in equipment that bears heavy and dynamic loads, high-strength structural steels, such as Q345, Q390, Q420, Q460, and Q500, are extensively used. Therefore, the substrate selected for spraying in this invention is at least one of structural steel and aluminum alloy, preferably one of Q345, Q390, Q420, Q460, and Q500, and more preferably Q345B structural steel.

[0020] The substrate is preferably a small round block with a diameter of Ф25*9mm; the substrate is roughened on the surface before use, preferably by surface sandblasting roughening.

[0021] The aforementioned high-hardness, wear-resistant, and corrosion-resistant composite ceramic coatings are preferred for surface protection of various workpieces and engineering structures in marine environments and areas with severe abrasion conditions near the sea, such as ship surfaces, offshore platforms, and bridge platforms located in tidal zones.

[0022] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0023] (1) This invention utilizes supersonic arc spraying technology to precisely control the parameters of each phase during spraying, causing pure titanium wire to melt under a high-temperature arc. High-pressure gas then atomizes the melt and rapidly deposits and diffuses it onto the substrate, forming a stable, robust, high-hardness, wear-resistant, and corrosion-resistant ceramic coating. Compared to other methods for preparing TiN-TiO... 2- TiN 0.3 The composite ceramic coating prepared by this invention has adjustable thickness and microstructure, and can achieve a layered and uniform distribution of titanium nitrides and oxides, wherein the ultra-hard phases TiN and TiN 0.3 The content exceeds 80%. Mainstream magnetron sputtering methods for preparing titanium-based wear-resistant coatings typically produce coatings with a thickness of 1-10 μm, but their protective effect and duration are limited. The coating method of this invention is simple, has no stringent requirements for application and processing environments, and boasts high preparation efficiency.

[0024] (2) Compared with the wear-resistant coating of titanium nitride alone, the present invention introduces TiO2, which is a semiconductor with special electrochemical properties. Without affecting the overall hardness of the coating, it enables it to have certain electrical functions and catalytic bactericidal functions. Attached Figure Description

[0025] Figure 1 The image shows the X-ray diffraction pattern of the coating.

[0026] Figure 2 The image shows the X-ray diffraction pattern at the interface between the coating and the substrate in Example 1.

[0027] Figure 3 The photoelectron scanning energy spectrum of the coating surface.

[0028] Figure 4 The surface morphology and cross-sectional morphology of hard wear-resistant coatings prepared under different spraying parameters are shown.

[0029] Figure 5 The SEM morphology of the wear tracks of the substrate and the hard wear-resistant coatings of Examples 1-3 under dry grinding under different normal loads of 5N and 10N, and under a normal load of 10N and a 3.5% NaCl corrosive environment.

[0030] Figure 6 The three-dimensional morphology of the wear tracks of the substrate and the hard wear-resistant coatings of Examples 1-3 under dry grinding with different normal loads of 5N and 10N, and under a normal load of 10N and a 3.5% NaCl corrosive environment.

[0031] Figure 7 The cross-sectional profiles of the friction wear tracks of the substrate and the hard wear-resistant coatings of Examples 1-3 under dry grinding with different normal loads of 5N and 10N, and under a normal load of 10N and a 3.5% NaCl corrosive environment.

[0032] Figure 8 The friction coefficient curves of the substrate and the hard wear-resistant coatings of Examples 1-3 under dry grinding under different normal loads of 5N and 10N, and under a normal load of 10N and a 3.5% NaCl corrosive environment.

[0033] Figure 9 This is a graph showing the wear rate variation of the substrate and hard wear-resistant coating under different frictional environments.

[0034] Figure 10 Load-displacement curves for nanoindentation tests on the substrate and hard wear-resistant coating.

[0035] Figure 11 The graph shows the changes in hardness and Young's modulus of the substrate and the hard wear-resistant coating. Detailed Implementation

[0036] The present invention will be further described in detail below with reference to embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto. Unless otherwise specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments used, unless otherwise specified, are all commercially available conventional products.

[0037] Example 1

[0038] Two pure titanium wires, 99.9% pure, 2.0mm in diameter, and 2000mm in length, were selected. Before spraying, the surface of the wires was cleaned with sandpaper to remove any adhering substances, and then ultrasonically cleaned. The substrate material surface was roughened by sandblasting and then cleaned. The wires and substrate material were then mounted on the wire feeding rollers at both ends of the spray gun and on the spraying fixture for the next step of arc spraying. In this example, the substrate material used was a small round block of Q345B structural steel (Ф25*9mm), and a high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating was prepared using the SX-1000 supersonic arc spraying equipment. The main parameters of the spraying process are: arc working voltage 42±1V, arc working current 80±10A, compressed air 0.8Mpa, spraying distance 120mm, horizontal movement speed of the spray gun 5mm / s, wire feeding speed 2, wire feeding speed at both ends of the spray gun 5m / min, spraying time without interval, continuous spraying for 10s.

[0039] The metal coating prepared in this example has a thickness of 300±30 μm, a bluish-gray surface, a dense surface structure, and an average porosity ≤5.0%. According to nanoindentation hardness testing, the coating has a hardness of 26±0.5 GPa and an elastic modulus of 240 MPa. The coating's hardness is 11 times higher than that of the Q345B structural steel substrate. Under dry grinding conditions with 5N and 10N normal loads, its wear resistance is 800% higher than the substrate. Under a 10N normal load and 3.5% NaCl corrosive environment, its wear resistance is 535% higher than the substrate. The main components of the coating are TiN, TiO2, and TiN2. 0.3 The results of EDS elemental analysis (X-ray diffraction elemental analysis of hard wear-resistant coating surface) are shown in Tables 1 and 4, where the scanned areas are as follows: Figure 4 As shown in the figure, the nitride content of the ultrahard phase titanium exceeds 80%.

[0040] Example 2

[0041] Two pure titanium wires, 99.9% pure, 1.2mm in diameter, and 4000mm in length, were selected. Before spraying, the surface of the wires was cleaned with sandpaper to remove any adhering substances, and then ultrasonically cleaned. The surface of the substrate material was roughened by sandblasting and then cleaned. The wires and substrate material were then mounted on the wire feeding rollers at both ends of the spray gun and on the spraying fixture for the next step of arc spraying.

[0042] This example uses small round blocks of Q345B structural steel (Ф25*9mm) as the substrate material. A high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating is prepared using an SX-1000 supersonic arc spraying system. The main parameters of the spraying process are: arc working voltage 42±1V, arc working current 100±10A, compressed air 0.8Mpa, spraying distance 150mm, horizontal movement speed of the spray gun 10mm / s, wire feed speed at 5 levels, and wire feed speed at both ends of the spray gun 7.5m / min. Spraying is continuous for 8 seconds without intervals.

[0043] The metal coating prepared in this example has a thickness of 250±30 μm, a dark gray surface, a dense surface structure, no obvious defects, and an average porosity ≤5.0%. According to nanoindentation hardness testing, the coating's hardness is 17±0.5 GPa, and its elastic modulus is 176 MPa. The coating's hardness is approximately 7 times higher than that of the Q345B structural steel substrate. Under dry grinding conditions with 5N and 10N normal loads, the wear resistance is 217% higher than the substrate, and under a 10N normal load and 3.5% NaCl corrosive environment, the wear resistance is 298% higher than the substrate. The main components of the coating are TiN, TiO2, and TiN2. 0.3 The results of EDS elemental analysis (X-ray diffraction elemental analysis of the hard wear-resistant coating surface are shown in Tables 2 and 4, where the scanned areas are as follows) Figure 4 As shown in the figure, the atomic ratio of nitrides in the ultrahard phase titanium exceeds 80%.

[0044] Example 3

[0045] Two pure titanium wires, 99.9% pure, 1.2mm in diameter, and 4000mm in length, were selected. Before spraying, the surface of the wires was cleaned with sandpaper to remove any adhering substances, and then ultrasonically cleaned. The surface of the substrate material was roughened by sandblasting and then cleaned. The wires and substrate material were then mounted on the wire feeding rollers at both ends of the spray gun and on the spraying fixture for the next step of arc spraying.

[0046] This example uses a small round block of Q345B structural steel with a diameter of Ф25*9mm as the substrate material. A high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating is prepared using an SX-1000 supersonic arc spraying machine. The main parameters of the spraying process are: arc working voltage 42±1V, arc working current 120±10A, compressed air 0.8Mpa, spraying distance 180mm, horizontal movement speed of the spray gun 15mm / s, and wire feed speed at level 11, approximately 9m / min. The spraying time is continuous for 25 seconds without intervals.

[0047] The metal coating prepared in this example has a thickness of 300±30 μm, a dark gray surface, a dense surface structure, and an average porosity ≤5.0%. According to nanoindentation hardness testing, the coating has a hardness of 24±0.5 GPa and an elastic modulus of 198 MPa. The coating's hardness is 9 times higher than that of the Q345B structural steel substrate. Under dry grinding conditions with 5N and 10N normal loads, its wear resistance is 1923% higher than the substrate, and under a 10N normal load and 3.5% NaCl corrosive environment, its wear resistance is 706% higher than the substrate. The main components of the coating are TiN, TiO2, and TiN2. 0.3 The results of EDS elemental analysis (X-ray diffraction elemental analysis of the hard wear-resistant coating surface are shown in Tables 3 and 4, where the scanned areas are as follows) Figure 4 As shown in the figure, the atomic ratio of nitrides in the ultrahard phase titanium exceeds 80%.

[0048] Table 1. Elemental analysis results of X-ray diffraction on the surface of the hard wear-resistant coating in Example 1.

[0049]

[0050] Table 2. Elemental analysis results of X-ray diffraction on the surface of the hard wear-resistant coating in Example 2.

[0051]

[0052] Table 3. Elemental analysis results of X-ray diffraction on the surface of the hard wear-resistant coating in Example 3.

[0053]

[0054] The atomic ratios of the components in each coating, after calculation, are shown in Table 4 below:

[0055] Table 4 shows the atomic ratios of the components in each coating in Examples 1-3.

[0056]

[0057] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating, characterized in that... The high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating is made of pure titanium wire through supersonic arc spraying and is TiN. 0.3 -TiO2-TiN composite ceramic coating; The high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating contains over 80% nitrides of the ultra-hard titanium phase. The process parameters for supersonic arc spraying are as follows: the arc working voltage is 30-42V, the arc working current is ≤150A, the wire feeding speed is 5m / min-9m / min, the compressed air pressure is ≥0.8Mpa, and the spraying distance is 120-180mm.

2. The high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating according to claim 1, characterized in that: The thickness of the high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating is 150-500μm.

3. The high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating according to claim 1, characterized in that: The purity of the pure titanium wire is ≥99.9%; The diameter of the pure titanium wire is 1.0-2.0 mm.

4. The high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating according to claim 1, characterized in that: The servo motor controlling the movement of the spray gun has a speed of 5-20 mm / s in the horizontal direction and 5-15 mm / s in the vertical direction, with a single spraying time of 5-10 seconds.

5. A method for preparing a high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating according to any one of claims 1-4, characterized in that... Includes the following steps: Pure titanium wire is fixed by a roller feeding device, and spraying is performed after the spraying parameters are set on the control panel to obtain a high-hardness, wear-resistant, and corrosion-resistant ceramic coating.

6. The application of the high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating according to any one of claims 1-4 in the surface protection of engineering equipment serving in marine environments.

7. The application of the high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating according to claim 6 in the surface protection of engineering equipment serving in marine environments, characterized in that... Engineering equipment used in marine environments includes ships and offshore operation platforms.

8. The application of the high-hardness, wear-resistant, and corrosion-resistant composite ceramic coating according to any one of claims 1-4 in stealth functional coatings.

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