Wear-resistant reinforced alloy coating and preparation process thereof

Abstract

The invention relates to a wear-resistant enhanced alloy coating and a preparation process thereof. The wear-resistant enhanced alloy coating is prepared from, by weight, 68-78 parts of nickel-based high-entropy alloy matrix, 21-31 parts of ceramic powder and 0.1-0.8 part of rare earth oxide. The surface of the ceramic powder is modified by a polyethylene glycol-polypropylene glycol block copolymer. According to the invention, the nickel-based high-entropy alloy matrix, the modified ceramic powder and the rare earth oxide are cooperated, so that the alloy coating has excellent performances of wear resistance, corrosion resistance and long-acting service stability.

Description

Technical Field

[0001] This application relates to the field of alloy materials and their preparation, and in particular to a wear-resistant reinforced alloy coating and its preparation process. Background Technology

[0002] With the booming development of the marine economy, ships are playing an increasingly prominent strategic role in marine transportation and marine resource development. Key components of ships, such as hulls, propellers, and thrusters, must operate for extended periods in complex marine environments characterized by high salinity, high humidity, and strong erosion. These environments present multiple challenges, including seawater corrosion, salt spray erosion, high-speed fluid scouring, and the adhesion of marine microorganisms, placing stringent demands on the protective performance of these components. Coatings, as the core barrier ensuring the safe operation of these critical components, directly determine their service life through their corrosion resistance, wear resistance, and operational stability, thus impacting the ship's operational safety and maintenance costs.

[0003] To address the challenge of protecting critical ship components, various protective coatings have been developed, with traditional alloy coatings being the most widely used. Chromium-containing alloy coatings, due to their corrosion resistance, once held a significant position in ship protection. However, the chromium in these coatings is highly toxic and easily released into the marine environment during manufacturing, service, and decommissioning, causing irreversible ecological pollution. This contradicts the current global concept of green ocean development, and their application has gradually been strictly limited. Against this backdrop, chromium-free environmentally friendly protective coatings, meeting environmental requirements, have become a research hotspot and development trend in the field of ship protection.

[0004] However, existing chromium-free protective coatings for ships still have significant technical shortcomings, making it difficult to meet the stringent service requirements of critical components. On the one hand, their wear resistance is poor; under high-speed seawater erosion, the coating is prone to wear and peeling, leading to direct exposure of the substrate and subsequent rapid corrosion failure. On the other hand, their corrosion protection capability is insufficient. Due to the lack of synergistic anti-corrosion effect of chromium, the coating is prone to pitting corrosion, microcracks, and other defects in long-term seawater immersion and salt spray environments. Corrosive media can quickly penetrate to the interface between the coating and the substrate through these defects, accelerating coating blistering and peeling, significantly shortening the service life of components, and seriously threatening the safety of ship navigation. Therefore, developing a chromium-free protective coating that combines excellent corrosion resistance, high wear resistance, and long-term stability has become an urgent technical challenge to be solved in the field of ship protection technology. Summary of the Invention

[0005] To improve the corrosion resistance and wear resistance of chromium-free protective coatings, this application provides a wear-resistant reinforced alloy coating and its preparation process.

[0006] In a first aspect, this application provides a wear-resistant reinforced alloy coating, which adopts the following technical solution: A wear-resistant reinforced alloy coating comprises the following components in parts by weight: 68-78 parts of nickel-based high-entropy alloy matrix, 21-31 parts of ceramic powder, and 0.1-0.8 parts of rare earth oxides; wherein the surface of the ceramic powder is modified with polyethylene glycol-polypropylene glycol block copolymer.

[0007] The inventors discovered that using ceramic powder modified with polyethylene glycol-polypropylene glycol block copolymer, in conjunction with a nickel-based high-entropy alloy matrix and rare earth oxides, enables the alloy coating to possess excellent properties such as wear resistance, corrosion resistance, and long-term stable service.

[0008] Specifically, adding ceramic particles to the coating composition helps resist the cutting and abrasion of sand and debris during seawater erosion of the alloy coating, reducing the loss of coating material. However, ceramic powder particles have numerous active sites on their surface, resulting in strong interparticle adsorption and a tendency to agglomerate. After modification with polyethylene glycol-polypropylene glycol block copolymer, the terminal hydroxyl groups of the polyethylene glycol segments form hydrogen bonds with the hydroxyl groups on the surface of the ceramic powder particles, thereby anchoring the polyethylene glycol-polypropylene glycol block copolymer onto the ceramic powder particles. At this time, the long polyether chains of the polypropylene glycol segments are fully extended in the solvent, resulting in a significant steric hindrance effect, which prevents the agglomeration of ceramic powder particles and provides strong dispersion stability. Furthermore, the polyethylene glycol-polypropylene glycol block copolymer decomposes into gaseous small molecules (such as CO2, H2O, and low-carbon alkanes) under vacuum at 400-600℃. These small molecules are removed from the gaps between the ceramic powder particles by the vacuum system, resulting in a very low risk of carbon residue. Moreover, there is no oxidation on the surface of the ceramic particles at this time, so no new active sites are generated. This results in low surface energy of the ceramic particles and weak interparticle adsorption, which is conducive to the formation of a pure metal-ceramic metallurgical bond, synergistically improving the dispersibility and interfacial strength of the alloy coating.

[0009] Nickel-based high-entropy alloy matrices, through the high-entropy effect formed by multi-element solid solution, construct uniform and stable face-centered cubic (FCC) or body-centered cubic (BCC) crystal structures, providing excellent matrix toughness and corrosion resistance for coatings. Their toughness buffers the impact stress from seawater erosion, preventing coating fracture due to stress concentration, while the corrosion-resistant substrate initially blocks the penetration of corrosive seawater media. Rare earth oxides improve the interfacial wettability between ceramic powder and the matrix, promoting a strong metallurgical bond and enhancing the interfacial bonding strength of the coating. Simultaneously, rare earth oxides can purify grain boundaries by adsorbing impurity atoms (such as oxygen and sulfur), inhibiting grain growth in the matrix. The refined nanoscale grains increase the number of grain boundaries, further hindering the penetration of corrosive media along these boundaries and enhancing the coating's corrosion resistance.

[0010] This application proposes a solution that utilizes a nickel-based high-entropy alloy matrix, modified ceramic powder, and rare earth oxides in synergy. These three components form a complementary and synergistic system of "matrix bearing capacity - ceramic wear resistance - rare earth enhancement," fundamentally solving the technical problem that chromium-free coatings, due to the lack of chromium's anti-corrosion synergistic effect, struggle to achieve both wear resistance and corrosion resistance.

[0011] In one specific feasible implementation, the mass ratio of the above-mentioned polyethylene glycol-polypropylene glycol block copolymer to ceramic powder is (0.3-0.8):100.

[0012] By using the above-mentioned proportions to modify the ceramic powder with polyethylene glycol-polypropylene glycol block copolymer, the modified ceramic powder exhibits excellent properties such as no residue and high dispersibility.

[0013] If the amount of polyethylene glycol-polypropylene glycol block copolymer added is insufficient, it cannot completely cover the active sites on the surface of the ceramic powder particles. These uncovered active sites become connection points for inter-particle agglomeration, leading to secondary agglomeration as the ceramic powder particles form hydrogen bonds or van der Waals forces through these sites. The agglomerated ceramic powder cannot be uniformly dispersed during subsequent coating preparation, resulting in particle enrichment defects in the coating. These defects become channels for corrosive media penetration, reducing the uniformity of coating hardness and making the enriched areas prone to cracking due to excessive brittleness.

[0014] If an excessive amount of polyethylene glycol-polypropylene glycol block copolymer is added, the block copolymer will form multilayer stacks on the surface of the ceramic powder. During the subsequent vacuum degreasing process, the stacked copolymer is difficult to completely decompose, resulting in free carbon impurities in the coating. These free carbon impurities will form irregularly distributed brittle carbides with the metal elements in the alloy matrix. These brittle carbides will reduce the plasticity and toughness of the coating. At the same time, the residual free carbon impurities will also form an isolation layer at the interface between the ceramic powder and the alloy matrix, increasing the interfacial bonding resistance between the ceramic powder and the alloy matrix. This leads to weak interfacial bonding, decreased coating density, and significantly reduced corrosion resistance, making the alloy coating prone to interfacial peeling and pitting failure after long-term seawater immersion.

[0015] In one specific implementation scheme, the ceramic powder is selected from one or more of titanium nitride powder, tungsten carbide powder, titanium carbide powder, and titanium diboride powder.

[0016] More preferably, the ceramic powder includes titanium nitride powder and tungsten carbide powder, wherein the mass ratio of titanium nitride powder to tungsten carbide powder is (3.5-4.5):1.

[0017] By using titanium nitride powder and tungsten carbide powder in the aforementioned synergistic ratio, both high hardness and impact erosion resistance of the coating are ensured, resulting in a significantly improved wear life. Titanium nitride, with its NaCl-type face-centered cubic crystal structure, exhibits high lattice stability, high Vickers hardness, excellent wear resistance, and good oxidation resistance. It is not easily oxidized to form a loose oxide film in seawater environments, thus balancing hardness and oxidation resistance. Tungsten carbide, with its hexagonal crystal structure and strong covalent bonds within the crystal, possesses high toughness and high erosion resistance. It is dispersed as hard particles within the alloy matrix. When the coating is subjected to external forces, the stress is distributed by the tungsten carbide particles, hindering dislocation movement and significantly improving the coating's toughness. The synergy of these two materials gives the ceramic powder both high hardness and high toughness.

[0018] If the proportion of titanium nitride powder is too high, the coating will become significantly more brittle, and microcracks or even peel off easily under strong seawater erosion or vibration conditions. If the proportion of titanium nitride powder is too low, the coating will have insufficient hardness and reduced wear resistance. At the same time, tungsten carbide is prone to slight decomposition during high-temperature smelting, releasing free carbon that forms irregular brittle carbides with the alloy matrix, thereby reducing the coating's corrosion resistance and bonding strength.

[0019] In one specific implementation scheme, the aforementioned nickel-based high-entropy alloy matrix comprises the following components in parts by weight: 26.0-30.0 parts nickel powder, 19.0-23.5 parts molybdenum powder, 24.0-29.0 parts tungsten powder, 8.5-12.0 parts niobium powder, 9.5-13.0 parts cobalt powder, 0.8-2.0 parts silicon powder, and 0.3-1.2 parts vanadium powder; More preferably, the nickel-based high-entropy alloy matrix comprises the following components in parts by weight: 28.0-28.5 parts nickel powder, 21.0-22.0 parts molybdenum powder, 26.0-27.0 parts tungsten powder, 10.0-10.5 parts niobium powder, 11.0-11.5 parts cobalt powder, 1.2-1.4 parts silicon powder, and 0.7-0.9 parts vanadium powder.

[0020] The inventors discovered that, based on the research on the above-mentioned synthetic composition, optimizing the content of nickel, molybdenum, tungsten, niobium, cobalt, silicon, and vanadium in the raw material components of the nickel-based high-entropy alloy matrix can improve the strength and toughness matching, seawater corrosion resistance, and compatibility with ceramic phases / rare earth oxides of the alloy matrix.

[0021] Specifically, within the optimized content range mentioned above, nickel and cobalt can form a stable face-centered cubic (FCC) solid solution matrix. Nickel, as the main metallic component, ensures smooth solid solution formation, while cobalt reduces the lattice distortion of nickel-based solid solutions. This avoids both the weakening of the high-entropy effect caused by excessive nickel content and the phase segregation problem caused by excessive cobalt content. The combination of the two also improves the interfacial wettability between the alloy matrix and the ceramic phase, preventing interfacial delamination due to poor wettability between the ceramic phase and the matrix. Molybdenum and tungsten can form a synergistic combination that is stable at high temperatures. Both are high-melting-point refractory elements, and when they are dissolved together into the matrix, they can significantly improve the high-temperature stability and wear-resistant hardness of the alloy matrix. At the same time, molybdenum can suppress the segregation of tungsten at grain boundaries, avoiding the formation of brittle intermetallic compounds due to excessive tungsten content, thereby achieving a balance between the hardness and plasticity of the alloy matrix.

[0022] Niobium and vanadium particles form a synergistic system for grain refinement and grain boundary purification. Niobium pins the grain boundaries to prevent grain coarsening, while vanadium adsorbs impurities such as oxygen and sulfur at the grain boundaries to purify them. At the same time, vanadium refines the as-cast structure and reduces overheating sensitivity, thus jointly improving the strength and toughness of the matrix.

[0023] Silicon, along with nickel, molybdenum, and cobalt, creates a synergistic effect of corrosion resistance and metallurgical bonding: silicon can improve the fluidity of the alloy matrix in the molten state and promote the formation of a good metallurgical bond between the matrix and the ceramic phase and substrate; at the same time, silicon, in combination with nickel and molybdenum, can form a dense oxide film containing SiO2 and NiO·MoO3 composite phases on the matrix surface, enhancing the matrix's resistance to seawater corrosion.

[0024] The combination of the above-mentioned multiple metallic elements within a limited content range can maximize the high entropy effect of the alloy matrix, allowing each element to achieve atomic-level uniform distribution, avoiding segregation and brittle phases, thus giving the alloy matrix excellent plasticity and toughness, and optimal compatibility with modified ceramic powder and rare earth oxides, providing a stable and highly adaptable load-bearing substrate for the alloy coating.

[0025] In one specific implementation scheme, the rare earth oxide is selected from one or two of cerium oxide and yttrium oxide; More preferably, the rare earth oxides include cerium oxide and yttrium oxide, and the mass ratio of cerium oxide to yttrium oxide is (1.5-2.3):1.

[0026] By synergistically combining cerium oxide and yttrium oxide in the aforementioned ratio, rare earth oxides exhibit excellent multi-effect synergy, including grain refinement, grain boundary purification, and enhanced interfacial bonding. Cerium oxide primarily refines grains and improves corrosion resistance, while yttrium oxide primarily enhances interfacial bonding and improves high-temperature stability. Within this ratio range, the two do not have antagonistic effects. Cerium oxide promotes the uniform distribution of yttrium oxide at grain boundaries, ensuring both nanoscale grain refinement of the matrix and strengthened interfacial anchoring between the ceramic powder and the matrix, simultaneously improving the coating's wear resistance, corrosion resistance, and service stability. If the cerium oxide ratio is too high, the interface strengthening effect is weakened, the interfacial bonding strength between ceramic powder and matrix decreases, and interface peeling is prone to occur. If the cerium oxide ratio is too low, the grain refinement and grain boundary purification effects are insufficient, the coating density is poor, the seawater corrosion resistance decreases, and excessive yttrium oxide is prone to forming enriched phases, increasing the brittleness of the coating.

[0027] Secondly, this application provides a preparation process for a wear-resistant reinforced alloy coating, employing the following technical solution: A process for preparing a wear-resistant reinforced alloy coating includes the following steps: S1. Vacuum dry the nickel-based high-entropy alloy matrix, ceramic powder, and rare earth oxides for later use. S2. Dissolve the polyethylene glycol-polypropylene glycol block copolymer in ethanol, add ceramic powder and disperse, then vacuum dry and transfer to a vacuum degreasing furnace for vacuum degreasing to obtain the modified ceramic powder. S3. Under inert gas conditions, the nickel-based high-entropy alloy matrix and rare earth oxides are ball-milled and mixed, and then the modified ceramic powder obtained in step S2 is added and ball-milled again to obtain homogenized alloy coating powder. S4. The alloy coating powder obtained in step S3 is used to form an alloy coating on the surface of the substrate through a laser cladding process.

[0028] The above four steps are typically used in synergy to achieve a dense, uniform, and highly wear- and corrosion-resistant alloy coating. First, vacuum drying removes impurities and moisture, preventing defects introduced by subsequent processes. Second, modification and degreasing of the ceramic powder ensures no residue between alloy coating components and adequate dispersibility. Next, stepwise ball milling achieves uniform dispersion of rare earth oxides before homogenization with the modified ceramic powder, preventing rare earth agglomeration and ceramic dispersion failure. Finally, rapid solidification using laser cladding locks in a uniform distribution of all components, inhibiting grain growth and phase segregation, ultimately resulting in a dense, defect-free, and stable wear-resistant reinforced coating.

[0029] In one specific implementation scheme, before the modified ceramic powder in step S3 is added, it is first ball-milled and sintered with a portion of the nickel-based high-entropy alloy matrix to form modified ceramic powder with a dense alloy coating layer. The mass ratio of the nickel-based high-entropy alloy matrix to the modified ceramic powder in the modified ceramic powder component with the dense alloy coating layer is 1:(0.02-0.04).

[0030] By using a portion of nickel-based high-entropy alloy matrix and modified ceramic powder to synergistically coat the composite powder in the above proportion before mixing, a dense alloy coating layer can be formed on the surface of the modified ceramic powder. This layer serves as a physical isolation layer to prevent secondary agglomeration of the ceramic powder. Furthermore, because the coating layer and the alloy matrix are of the same origin, metallurgical-grade bonding between the ceramic powder and the matrix is ​​achieved, improving the interfacial bonding strength. At the same time, the wear resistance of the ceramic is not weakened due to excessive coating thickness, thus achieving a dual improvement in dispersibility and anchoring.

[0031] In summary, this application includes at least one of the following beneficial technical effects: 1. This application utilizes ceramic powder modified with polyethylene glycol-polypropylene glycol block copolymer, in conjunction with a nickel-based high-entropy alloy matrix and rare earth oxides, to enable the alloy coating to possess excellent properties such as wear resistance, corrosion resistance, and long-term stable service.

[0032] 2. This application optimizes the content of nickel, molybdenum, tungsten, niobium, cobalt, silicon, and vanadium in the raw material composition of the nickel-based high-entropy alloy matrix, thereby improving the strength and toughness matching, seawater corrosion resistance, and compatibility with ceramic phases / rare earth oxides of the alloy matrix.

[0033] 3. This application achieves excellent performance of rare earth oxides by using cerium oxide and yttrium oxide in an optimized compound ratio, thereby enabling them to refine grains, purify grain boundaries, and enhance interfacial synergy. Detailed Implementation

[0034] The present application will be further described in detail below with reference to embodiments and comparative examples: Some of the raw materials used in the examples and comparative examples: Nickel powder, molybdenum powder, tungsten powder, niobium powder, cobalt powder, silicon powder, and vanadium powder are all micron-sized spherical metal powders; titanium nitride powder has a specification of 1µm, and tungsten carbide powder has a specification of 100-325 mesh, both being spherical ceramic powders; cerium oxide has a specification of 50nm, and yttrium oxide has a specification of 50nm, both having a spherical crystal structure. All the above metal powders, nitride powders, carbide powders, and rare earth oxides were purchased from Shanghai Naio Nanotechnology Co., Ltd.

[0035] Polyethylene glycol-polypropylene glycol block copolymer (also known as poloxamer, product number: F127, purchased from Guangzhou Bolu Chemical Co., Ltd.); polyethylene glycol (product number: PEG400, purchased from Jinan Yuhangyuan New Materials Co., Ltd.); polypropylene glycol (product number: DL-400, purchased from Tianjin Zhonghe Shengteng Chemical Co., Ltd.).

[0036] Unless otherwise specified, all raw materials used in the examples and comparative examples are commercially available products.

[0037] Preparation Example 1 Powder mixing of nickel-based high-entropy alloy matrix: 28.2 parts by weight of nickel powder, 21.5 parts by weight of molybdenum powder, 26.5 parts by weight of tungsten powder, 10.4 parts by weight of niobium powder, 11.3 parts by weight of cobalt powder, 1.3 parts by weight of silicon powder and 0.8 parts by weight of vanadium powder were weighed and mixed, and then subjected to high-energy ball milling for 8 hours under inert gas protection to obtain a uniformly mixed nickel-based high-entropy alloy matrix.

[0038] Preparation Example 2 The difference between Preparation Example 2 and Preparation Example 1 is that in Preparation Example 2, 28.2 parts by weight of nickel powder and 11.3 parts by weight of cobalt powder were replaced with 31.5 parts by weight of nickel powder and 8.3 parts by weight of cobalt powder.

[0039] Preparation Example 3 The difference between Preparation Example 3 and Preparation Example 1 is that in Preparation Example 3, 28.2 parts by weight of nickel powder and 11.3 parts by weight of cobalt powder were replaced with 25.2 parts by weight of nickel powder and 14.3 parts by weight of cobalt powder.

[0040] Preparation Example 4 The difference between Preparation Example 4 and Preparation Example 1 is that in Preparation Example 4, 21.5 parts by weight of molybdenum powder and 26.5 parts by weight of tungsten powder are replaced with 17.5 parts by weight of molybdenum powder and 30.5 parts by weight of tungsten powder.

[0041] Preparation Example 5 Mixing of ceramic powder: 80 parts by weight of titanium nitride and 20 parts by weight of tungsten carbide powder were mixed evenly to obtain ceramic powder.

[0042] Preparation Example 6 Mixing of ceramic powder: 90 parts by weight of titanium nitride and 10 parts by weight of tungsten carbide powder were mixed evenly to obtain ceramic powder.

[0043] Preparation Example 7 Mixing of ceramic powder: Ceramic powder is obtained by mixing 60 parts by weight of titanium nitride and 40 parts by weight of tungsten carbide powder.

[0044] Preparation Example 8 Mixing of rare earth oxides: 65 parts by weight of cerium oxide and 35 parts by weight were stirred and mixed to obtain rare earth oxides.

[0045] Preparation Example 9 Mixing of rare earth oxides: Rare earth oxides were obtained by stirring and mixing 80 parts by weight of cerium oxide and 20 parts by weight of yttrium oxide.

[0046] Preparation Example 10 Mixing of rare earth oxides: Rare earth oxides were obtained by stirring and mixing 50 parts by weight of cerium oxide and 50 parts by weight of yttrium oxide. Example

[0047] Example 1 The preparation process of the alloy coating is as follows: S1. The nickel-based high-entropy alloy matrix prepared in Preparation Example 1, the ceramic powder prepared in Preparation Example 5, and the rare earth oxide prepared in Preparation Example 8 are vacuum dried for later use. S2. Dissolve 0.5 parts by weight of polyethylene glycol-polypropylene glycol block copolymer in 300 parts by weight of ethanol, add 100 parts by weight of ceramic powder prepared in Preparation Example 5, stir at room temperature for 1 hour to obtain a dispersed suspension; suspend the suspension under a vacuum of 10... -2 Under the conditions of Pa, it was vacuum dried at 80°C for 2 hours, and then transferred to a vacuum degreasing oven at a vacuum degree of 10. -4 The temperature was raised to 650℃ and held for 2.5 hours under the conditions of Pa and a heating rate of 5℃ / min, and then vacuum degreasing was performed to obtain the modified ceramic powder. S2.1. Place 100 parts by weight of the modified ceramic powder obtained in step S2 and 3 parts by weight of the nickel-based high-entropy alloy matrix obtained in Preparation Example 1 into a vacuum planetary ball mill and ball mill at a speed of 200 r / min for 1 hour. Then transfer it to a vacuum plasma coating furnace and ball mill at a vacuum degree of 10. -4 Under conditions of Pa and plasma power of 800W, the modified ceramic powder was held at 800℃ for 1 hour to form an initial coating layer on its surface. Then, it was transferred to a vacuum sintering furnace at a vacuum degree of 10... -3 Under the condition of heating rate of 8℃ / min, the temperature is raised to 1150℃ and held for 1.5 hours to form modified ceramic powder with a dense alloy coating layer. S3. Under inert gas conditions, 73 parts by weight of the nickel-based high-entropy alloy matrix prepared in Preparation Example 1 and 0.6 parts by weight of the rare earth oxide prepared in Preparation Example 8 were ball-milled and mixed. Then, 26.4 parts by weight of the modified ceramic powder coated with a dense alloy coating layer prepared in step S2.1 were added and ball-milled again to obtain homogenized alloy coating powder. S4. The alloy coating powder obtained in step S3 is used in a laser cladding process with a laser power of 1200w, a scanning speed of 400mm / min, and a powder feeding speed of 10g / min. A single-layer multi-pass path is adopted, and the spot diameter is controlled at 5mm and the overlap rate is 50% to form an alloy coating on the substrate surface.

[0048] Example 2 The only difference between Example 2 and Example 1 is that the preparation process of Example 2 does not include step S2.1. The preparation process of Example 2 is as follows: S1. The nickel-based high-entropy alloy matrix prepared in Preparation Example 1, the ceramic powder prepared in Preparation Example 5, and the rare earth oxide prepared in Preparation Example 8 are vacuum dried for later use. S2. Dissolve 0.5 parts by weight of polyethylene glycol-polypropylene glycol block copolymer in 300 parts by weight of ethanol, add 100 parts by weight of ceramic powder prepared in Preparation Example 5, stir at room temperature for 1 hour to obtain a dispersed suspension; suspend the suspension under a vacuum of 10... -2 Under the conditions of Pa, it was vacuum dried at 80°C for 2 hours, and then transferred to a vacuum degreasing oven at a vacuum degree of 10. -4The temperature was raised to 650℃ and held for 2.5 hours under the conditions of Pa and a heating rate of 5℃ / min, and then vacuum degreasing was performed to obtain the modified ceramic powder. S3. Under inert gas conditions, 73 parts by weight of the nickel-based high-entropy alloy matrix prepared in Preparation Example 1 and 0.6 parts by weight of the rare earth oxide prepared in Preparation Example 8 were ball-milled and mixed. Then, 26.4 parts by weight of the modified ceramic powder prepared in step S2 were added and ball-milled again to obtain homogenized alloy coating powder. S4. The alloy coating powder obtained in step S3 is used in a laser cladding process with a laser power of 1200w, a scanning speed of 400mm / min, and a powder feeding speed of 10g / min. A single-layer multi-pass path is adopted, and the spot diameter is controlled at 5mm and the overlap rate is 50% to form an alloy coating on the substrate surface.

[0049] Example 3 The only difference between Example 3 and Example 1 is that in the preparation process of Example 3, all nickel-based high-entropy alloy matrices obtained in Preparation Example 1 are replaced with nickel-based high-entropy alloy matrices obtained in Preparation Example 2.

[0050] Example 4 The only difference between Example 4 and Example 1 is that in the preparation process of Example 4, all nickel-based high-entropy alloy matrices obtained in Preparation Example 1 are replaced with nickel-based high-entropy alloy matrices obtained in Preparation Example 3.

[0051] Example 5 The only difference between Example 5 and Example 1 is that in the preparation process of Example 5, all nickel-based high-entropy alloy matrices obtained in Preparation Example 1 are replaced with nickel-based high-entropy alloy matrices obtained in Preparation Example 4.

[0052] Example 6 The only difference between Example 6 and Example 1 is that in the preparation process of Example 6, all the ceramic powders obtained in Preparation Example 5 are replaced with the ceramic powders obtained in Preparation Example 6.

[0053] Example 7 The only difference between Example 7 and Example 1 is that in the preparation process of Example 7, all the ceramic powders obtained in Preparation Example 5 are replaced with the ceramic powders obtained in Preparation Example 7.

[0054] Example 8 The only difference between Example 8 and Example 1 is that in the preparation process of Example 8, all the rare earth oxides obtained in Preparation Example 8 are replaced with the rare earth oxides obtained in Preparation Example 9.

[0055] Example 9 The only difference between Example 9 and Example 1 is that in the preparation process of Example 9, all the rare earth oxides obtained in Preparation Example 8 are replaced with the rare earth oxides obtained in Preparation Example 10.

[0056] Comparative Example 1 The only difference between Comparative Example 1 and Example 1 is that the preparation process of Comparative Example 1 does not include the original steps S2 and S2.1. The preparation process of Comparative Example 1 is as follows: S1. The nickel-based high-entropy alloy matrix prepared in Preparation Example 1, the ceramic powder prepared in Preparation Example 5, and the rare earth oxide prepared in Preparation Example 8 are vacuum dried for later use. Under S2 and inert gas conditions, 73 parts by weight of the nickel-based high-entropy alloy matrix prepared in Preparation Example 1 and 0.6 parts by weight of the rare earth oxide prepared in Preparation Example 8 were ball-milled and mixed, and then 26.4 parts by weight of the ceramic powder prepared in Preparation Example 5 were added and ball-milled again to obtain homogenized alloy coating powder. S3. The alloy coating powder obtained in step S2 is used in a laser cladding process with a laser power of 1200w, a scanning speed of 400mm / min, and a powder feeding speed of 10g / min. A single-layer multi-pass path is adopted, and the spot diameter is controlled at 5mm and the overlap rate is 50% to form an alloy coating on the substrate surface.

[0057] Comparative Example 2 The only difference between Comparative Example 2 and Example 1 is that in the preparation process of Comparative Example 2, 0.5 parts by weight of polyethylene glycol-polypropylene glycol block copolymer in step S2 is replaced with 0.5 parts by weight of polyethylene glycol.

[0058] Comparative Example 3 The only difference between Comparative Example 3 and Example 1 is that in the preparation process of Comparative Example 3, 0.5 parts by weight of polyethylene glycol-polypropylene glycol block copolymer in step S2 is replaced with 0.5 parts by weight of polypropylene glycol.

[0059] The alloy coatings prepared in each embodiment and comparative example were tested for wear resistance in accordance with GB / T 12444.3-2008 "Metallic materials wear test - Part 3: erosion wear test" and for corrosion resistance in accordance with GB / T 10125-2021 "Artificial atmosphere corrosion test - salt spray test" (NSS test, simulating marine salt spray environment).

[0060] 1. Abrasion resistance test conditions: The medium is 3.5% NaCl simulated seawater, the flow rate is 3m / s (matching the service flow rate of ship propellers and thrusters), the scouring angle is 30°, the scouring time is 2h, the sample size is 50mm×25mm×5mm, the mass difference before and after wear is recorded, and the wear amount (mg) is calculated.

[0061] 2. Neutral salt spray test conditions: 5% NaCl solution, temperature 35℃, salt spray deposition rate 1-2mL / (80cm²·h), continuous spraying, and observation of the time it takes for the coating to develop corrosive spots.

[0062] The test data are all summarized in Table 1. Table 1. Test data on corrosion resistance and wear resistance of alloy coatings obtained in each embodiment and comparative example. Test Project Wear amount (mg) Salt spray tolerance time (h) Example 1 12 2850 Example 2 24 2050 Example 3 17 2350 Example 4 20 2200 Example 5 15 2450 Example 6 13 2650 Example 7 18 2300 Example 8 14 2500 Example 9 16 2400 Comparative Example 1 48 1350 Comparative Example 2 30 1600 Comparative Example 3 40 1450 As shown in Table 1 above, the test results indicate that by utilizing the technical solution of this application, and by optimizing the composition ratio of the nickel-based high-entropy alloy matrix, the ceramic powder compounding ratio, and the synergistic ratio of rare earth oxides, and by employing a synergistic preparation process of polyethylene glycol-polypropylene glycol block copolymer modified ceramic powder, combined with high-temperature alloy coating, stepwise ball milling, and laser cladding, the resulting wear-resistant and reinforced chromium-free marine alloy coating exhibits excellent wear resistance and salt spray resistance, making it suitable for more complex marine environments (such as high-speed seawater erosion and long-term salt spray corrosion conditions). This reduces the maintenance cost of ship coatings and improves the economy and safety of ship operation.

[0063] By comparing Examples 1 and 2, and Comparative Examples 1-3, and referring to the data in Table 1, it can be seen that the wear resistance and corrosion resistance of Example 1 are superior to those of Example 2 and Comparative Examples 1-3. This may be because the use of polyethylene glycol-polypropylene glycol block copolymer to modify the ceramic powder allows the ceramic powder to be dispersed more evenly in the medium, leaving no residue after degreasing and avoiding pore defects in the coating. Combined with the high-temperature alloy coating process, the interfacial bonding force between the ceramic powder and the substrate can be enhanced, the difference in thermal expansion coefficient can be eliminated, cracks can be prevented during laser cladding, and the wear resistance and corrosion resistance of the coating can be significantly improved.

[0064] Combining Examples 1 and 3-5, and referring to the data in Table 1, it can be seen that the abrasion resistance and corrosion resistance of Example 1 are better than those of Examples 3-5. This may be because the optimized ratio of nickel, cobalt, molybdenum and tungsten can form a stable solid solution structure, taking into account both the toughness and plasticity of the metal matrix; at the same time, the precipitation of uniform and fine carbide phases improves the hardness and pitting resistance of the coating, which is suitable for the service requirements of key ship components.

[0065] Combining Examples 1 and 6-7, and referring to the data in Table 1, it can be seen that the wear resistance and corrosion resistance of Example 1 are better than those of Examples 6-7. This may be because the ceramic powder prepared by titanium nitride and tungsten carbide in the optimal compounding ratio provides stable salt spray corrosion resistance and structural support from titanium nitride, while tungsten carbide acts as a reinforcing phase to effectively resist high-speed seawater erosion, thus achieving complementary corrosion resistance and wear resistance.

[0066] Combining Examples 1 and 8-9, and referring to the data in Table 1, it can be seen that the abrasion resistance and corrosion resistance of Example 1 are superior to those of Examples 8-9. This may be because the synergistic ratio of cerium oxide and yttrium oxide rare earth oxides achieves the dual effects of grain boundary purification and grain refinement. Cerium oxide can combine with impurities such as oxygen and sulfur in the coating, avoiding intergranular corrosion caused by grain boundary segregation; yttrium oxide refines the grains through heterogeneous nucleation, improving the overall mechanical properties.

[0067] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A wear resistant, reinforced alloy coating, characterized in that, The components include the following weight parts: a nickel-based high-entropy alloy matrix 68-78 parts, a ceramic powder 21-31 parts, and a rare earth oxide 0.1-0.8 parts; the surface of the ceramic powder is modified by a polyethylene glycol-polypropylene glycol block copolymer.

2. The wear-resistant, reinforced alloy coating of claim 1, wherein, The mass ratio of the polyethylene glycol-polypropylene glycol block copolymer to the ceramic powder is (0.3-0.8):

100.

3. The wear-resistant, reinforced alloy coating of claim 1, wherein, The ceramic powder is selected from one or more of titanium nitride powder, tungsten carbide powder, titanium carbide powder, and titanium diboride powder.

4. The wear-resistant, reinforced alloy coating of claim 1, wherein, The ceramic powder includes titanium nitride powder and tungsten carbide powder, and the mass ratio of the titanium nitride powder to the tungsten carbide powder is (3.5-4.5):

1.

5. The wear-resistant, reinforced alloy coating of claim 1, wherein, The nickel-based high-entropy alloy matrix includes the following components by weight: nickel powder 26.0-30.0 parts, molybdenum powder 19.0-23.5 parts, tungsten powder 24.0-29.0 parts, niobium powder 8.5-12.0 parts, cobalt powder 9.5-13.0 parts, silicon powder 0.8-2.0 parts, and vanadium powder 0.3-1.2 parts.

6. The wear-resistant, reinforced alloy coating of claim 5, wherein, The nickel-based high-entropy alloy matrix includes the following components by weight: nickel powder 28.0-28.5 parts, molybdenum powder 21.0-22.0 parts, tungsten powder 26.0-27.0 parts, niobium powder 10.0-10.5 parts, cobalt powder 11.0-11.5 parts, silicon powder 1.2-1.4 parts, and vanadium powder 0.7-0.9 parts.

7. The wear-resistant, reinforced alloy coating of claim 1, wherein, The rare earth oxide is selected from one or both of cerium oxide and yttrium oxide.

8. The wear-resistant, reinforced alloy coating of claim 7, wherein, The rare earth oxide includes cerium oxide and yttrium oxide, and the mass ratio of the cerium oxide to the yttrium oxide is (1.5-2.3):

1.

9. A process for the production of a wear resistant, reinforced alloy coating according to any one of claims 1 to 8, characterized in that, The following preparation steps are included: S1, vacuum drying of a nickel-based high-entropy alloy matrix, a ceramic powder, and a rare earth oxide for standby; S2, dissolving a polyethylene glycol-polypropylene glycol block copolymer in ethanol, adding a ceramic powder, dispersing, vacuum drying, vacuum degreasing in a vacuum degreasing furnace, and obtaining a modified ceramic powder; S3, under inert gas conditions, ball milling a nickel-based high-entropy alloy matrix and a rare earth oxide, then adding the modified ceramic powder obtained in step S2 for further ball milling, and obtaining a homogenized alloy coating powder; S4, forming an alloy coating on the surface of a substrate by a laser cladding process.

10. The process for the production of a wear resistant, reinforced alloy coating according to claim 9, characterized in that, Before the modified ceramic powder in step S3 is added, it is first ball milled with part of the nickel-based high-entropy alloy matrix and then sintered, forming a modified ceramic powder coated with a dense alloy coating layer, and the mass ratio of the nickel-based high-entropy alloy matrix to the modified ceramic powder in the composition of the modified ceramic powder coated with a dense alloy coating layer is 1:(0.02-0.04).