Wear-resistant and corrosion-resistant high-manganese copper alloy and preparation method thereof

Abstract

The present application belongs to the technical field of copper alloy, and particularly relates to a wear-resistant and corrosion-resistant high-manganese copper alloy and a preparation method thereof, characterized by the following composition by weight percentage (wt.%): Mn: 20% to 35%, Al: 5% to 7%, Ni: 10% to 14%, and the balance of Cu and inevitable impurities, with the total percentage of all impurities being not more than 0.5%, and the content of any one of Pb, Sn, Si, Zn, P and S being not more than 0.1%. The preparation method comprises the following steps: 1) batching; 2) smelting; 3) pouring; and 4) solid solution treatment, to obtain the wear-resistant and corrosion-resistant high-manganese copper alloy. The present application has the following beneficial effects: innovative alloy composition, tensile strength up to 585 MPa, yield strength up to 296 MPa, hardness up to 305 HV, friction coefficient as low as 0.43, corrosion current density as low as 3.95 x 10 ‑6 A / cm 2 , and excellent comprehensive performance, and can be widely applied to pump bodies, valve bodies, pipelines, propellers and other parts in marine environments and other occasions with high requirements for wear resistance and corrosion resistance.

Description

Technical Field

[0001] This invention belongs to the field of copper alloy technology, and particularly relates to a wear-resistant and corrosion-resistant high-manganese copper alloy and its preparation method. Background Technology

[0002] For large-scale equipment built in marine environments, copper alloys are one of the mainstay marine materials currently in service, possessing irreplaceable advantages in shipbuilding, marine engineering, and other fields. Compared to cast iron, carbon steel, and low-alloy steel, copper alloys have a higher electrode potential, exhibit greater stability in marine environments, and possess excellent resistance to seawater corrosion. Compared to corrosion-resistant stainless steel, titanium, and titanium alloys, copper alloys release toxic cuprous ions upon dissolution, effectively inhibiting the growth and attachment of marine microorganisms, thus exhibiting unique antifouling and anti-fouling properties. However, due to the harshness and complex, variable nature of marine corrosion and abrasion environments, the service life of copper alloys is reduced, resulting in significant economic losses.

[0003] Chinese invention patent CN113718130A discloses a cast high-strength manganese-aluminum bronze alloy and its preparation method, aiming to meet the demand for high-strength valve body casting materials in the development of naval technology. This patent uses rare-earth-containing deoxidizers and refining agents to improve the alloy's performance and quality. However, the deoxidation and refining steps involved in the preparation process require precise control and specific technical and equipment support, thus increasing the complexity of the process. Furthermore, beryllium added to the alloy is a toxic element, which may pose risks to the environment and human health during production and use.

[0004] Chinese invention patent CN110106393A discloses a high-manganese wear-resistant aluminum bronze alloy and its preparation method, aiming to meet the demand for high-strength, wear-resistant copper parts in high-performance hydraulic pumps in the machinery industry. This alloy, while ensuring high tensile strength, high yield strength, and excellent elongation, exhibits superior wear resistance compared to traditional bronze alloys under poor lubrication conditions. However, the preparation process involves precise melting, annealing, and extrusion steps, placing high demands on production equipment and process control.

[0005] Foreign invention patent publication number WO2022 / 070905A1 discloses a wear-resistant manganese-aluminum bronze casting alloy with excellent hardness and machinability. This alloy optimizes its physical properties by precisely controlling the content of aluminum and manganese, while adding lead or bismuth to increase cutting speed and reduce tool wear. Although this alloy exhibits excellent wear resistance and free-machining performance, its strict compositional limitations, processing difficulty, environmental impact, and cost issues still require attention. Furthermore, excessively high aluminum content may lead to material brittleness, and specific heat treatment requirements may increase the complexity of the production process.

[0006] Chinese invention patent CN113584343B discloses a corrosion-resistant high-manganese aluminum bronze alloy and its preparation method, specifically for applications such as the inner wall of hydraulic cylinders. This alloy, through a unique compositional design, significantly improves corrosion resistance, especially performing excellently in acidic environments with a pH of 3. However, this invention primarily targets the welding material for the inner wall of hydraulic cylinders and may not be suitable for other types of corrosive environments or different engineering applications, limiting the alloy's versatility. Furthermore, the alloy's high strength and hardness may lead to work hardening problems, making machining and forming processes more difficult.

[0007] US Patent No. US2011 / 0226138A1 discloses a wear-resistant and corrosion-resistant copper-nickel-manganese alloy, specifically designed for machining applications where high corrosion and wear resistance of parts are required. This alloy achieves high strength and hardness through precise compositional adjustments, exhibiting superior mechanical properties compared to traditional alloys. However, the high nickel content results in higher material costs, and the processing may require more complex technologies and equipment.

[0008] Chinese invention patent CN115213586A discloses a wear-resistant and corrosion-resistant manganese-aluminum bronze welding wire and its preparation method. It employs an upward continuous casting and continuous extrusion process, which not only improves production efficiency and output but also effectively reduces costs. The continuous extrusion process helps refine the material microstructure and eliminate defects such as porosity, segregation, and micro-voids on the surface of the continuously cast rod. While this represents an improvement over some traditional processes, the production process still involves multiple steps, which may result in a longer production cycle.

[0009] Analysis of existing patent technologies and literature reveals that manganese bronze typically contains 10%–15% manganese, 7%–9% aluminum, and 1%–5% nickel. While this provides certain mechanical and corrosion resistance properties, it falls short of the high-performance requirements of extreme service environments such as marine engineering. Although existing manganese bronzes possess high strength and hardness, their service life in marine environments is limited, and they are ill-suited to resist corrosion from various media, failing to meet higher corrosion resistance requirements. Therefore, developing a novel high-manganese copper alloy, through optimized alloy composition design and manufacturing processes, to achieve a synergistic improvement in wear resistance, corrosion resistance, and mechanical properties, is of great significance for effectively extending the service life of manganese bronze and adapting it to more service environments to meet the needs of high-end applications such as marine engineering. Summary of the Invention

[0010] The purpose of this invention is to provide a wear-resistant and corrosion-resistant high-manganese copper alloy and its preparation method, overcoming the shortcomings of the prior art. By adopting a multi-element alloying design and adding aluminum, nickel, chromium and rare earth element Y, the comprehensive mechanical properties, wear resistance and corrosion resistance of the copper alloy are improved, ensuring that the alloy has good processing performance, meeting the needs of high-end application fields such as marine engineering, extending service life and adapting to more service environments.

[0011] To achieve the above objectives, the technical solution of the present invention is as follows: One technical solution is a wear-resistant and corrosion-resistant high-manganese copper alloy, wherein the composition of the material by weight percentage (wt.%) is: Mn: 20%~35%, Al: 5%~7%, Ni: 10%~14%, with the balance being Cu and unavoidable impurities, the total proportion of all impurities not exceeding 0.5%, and the content of any one of Pb, Sn, Si, Zn, P, and S not exceeding 0.1%.

[0012] Technical Solution Two: A method for preparing a wear-resistant and corrosion-resistant high-manganese copper alloy, specifically including the following steps: 1) Ingredient preparation: Prepare raw materials according to the component ratio and clean the surfaces; 2) Smelting: Place the nickel plate and copper plate in a crucible, sprinkle the flux cryolite and the covering agent charcoal powder on their surface, then heat to 1300~1350℃. After observing the molten metal, add manganese flakes and stir with a stirring rod to make it fully melted. After it is completely melted, add phosphor bronze for the first degassing. After observing that the gas has completely escaped, keep it at the temperature for 10 minutes, then add aluminum blocks. After the aluminum blocks are completely melted, add phosphor bronze again for the second degassing. After the gas is completely removed, keep it at the temperature for 10 minutes, and then remove the slag to obtain the molten metal. 3) Casting: Molten metal at a temperature of 1250~1300℃ is poured into a metal mold to obtain a copper alloy ingot; 4) Solution treatment: After solution treatment of the copper alloy ingot, wear-resistant and corrosion-resistant high-manganese copper alloy is obtained.

[0013] Technical Solution 3: A wear-resistant and corrosion-resistant high-manganese copper alloy, wherein the composition of the material by weight percentage (wt.%) is: Mn: 20%~35%, Al: 5%~7%, Ni: 10%~14%, Cr: 0.6%~1.5%, Y: 0.2%~1%, with the balance being Cu and unavoidable impurities, wherein the total percentage of all impurities is not greater than 0.5%, and the content of any one of Pb, Sn, Si, Zn, P, and S is not greater than 0.1%.

[0014] Technical Solution Four: A method for preparing a wear-resistant and corrosion-resistant high-manganese copper alloy, specifically including the following steps: 1) Ingredient preparation: Prepare raw materials according to the component ratio and clean the surfaces; 2) Smelting: Place the nickel plate and copper plate in a crucible, sprinkle the flux cryolite and the covering agent charcoal powder on their surface, and then heat to 1300~1350℃. After observing the molten metal, add manganese flakes and stir with a stirring rod to make it fully melted. After it is completely melted, add phosphor bronze for the first degassing. After observing that the gas has completely escaped, add Cu-Cr master alloy with a Cr content of 10wt.%, hold for 10 minutes, and then add aluminum blocks. After the aluminum blocks are completely melted, add phosphor bronze again for the second degassing. After the gas is completely removed, add Cu-Y master alloy with a Y content of 15wt.%, hold for 10 minutes, and then remove the slag to obtain the molten metal. 3) Casting: Molten metal at a temperature of 1250~1300℃ is poured into a metal mold to obtain a copper alloy ingot; 4) Solution treatment: After solution treatment of the copper alloy ingot, wear-resistant and corrosion-resistant high-manganese copper alloy is obtained.

[0015] The phosphor bronze is a Cu-P master alloy with a P content of 8 wt.%, and the amount used is 1% to 2% of the total alloy mass. The residual P element in the molten metal is no more than 0.1%.

[0016] The cryolite has the molecular formula Na3AlF6 and is used in an amount of 0.2% to 0.4% of the total alloy mass; the charcoal powder is composed of carbon and is used in an amount of 0.4% to 0.6% of the total alloy mass.

[0017] The solution treatment temperature in step 4) is 900-980℃, the holding time is 2-3 hours, and the cooling method is water cooling to room temperature.

[0018] In step 1), the raw materials are any two or more combinations of pure nickel plates, pure copper plates, pure aluminum blocks, pure manganese sheets, Cu-Cr master alloy with a Cr content of 10 wt.% and Cu-Y master alloy with a Y content of 15 wt.%, and the purity of the pure nickel plates, pure copper plates, pure aluminum blocks and pure manganese sheets is 99% or higher.

[0019] The surface treatment method in step 1) is to grind with an angle grinder or clean with a shot blasting machine to remove the thick oxide scale and rust layer on the surface of the raw material, and then put the raw material into an oven at 150°C to dry for at least 1 hour to remove the moisture adsorbed on the surface of the raw material.

[0020] The wear-resistant and corrosion-resistant high-manganese copper alloy has a tensile strength of up to 585 MPa, a yield strength of up to 296 MPa, a hardness of up to 305 HV, a friction coefficient as low as 0.43, and a corrosion current density as low as 3.95 × 10⁻⁶. -6 A / cm 2 .

[0021] In this invention, manganese can be readily dissolved in copper and exhibits strong solid solution strengthening properties. Increasing the manganese content significantly improves the strength and hardness of the alloy. Increasing the manganese content shrinks the α-phase region of the copper alloy, significantly lowers the eutectoid transformation temperature of the β-phase, thereby improving the stability of the β-phase and suppressing "slow cooling brittleness." Furthermore, increasing the manganese content enhances the alloy's corrosion resistance, mechanical properties, and wear resistance. Increasing the manganese content lowers the alloy's melting point, increases its fluidity, and facilitates deoxidation and degassing, thus improving the alloy's casting performance and enhancing the quality of castings.

[0022] Aluminum is one of the key elements determining the strength of alloys and has a significant impact on plasticity. With increasing aluminum content, the alloy matrix transforms from the α phase to the α+β phase, leading to a decrease in plasticity. Therefore, controlling the aluminum content at a low level helps improve the material's plasticity and formability. Although aluminum has low solubility in copper alloys, it has a significant strengthening effect, greatly improving the alloy's mechanical strength and enhancing its erosion resistance. During corrosion, aluminum can form a tough and dense protective film on the alloy surface, thereby reducing its corrosion susceptibility in media such as sulfates and caustic alkalis, enhancing erosion resistance, reducing surface activity, and improving corrosion resistance.

[0023] The addition of nickel can increase the corrosion potential and passivation ability of copper alloys. Furthermore, Ni and Cu are infinitely soluble in each other, further enhancing the mechanical properties of the alloy and significantly improving its corrosion resistance. Nickel can dissolve in α-solid solutions, thereby strengthening the alloy. On one hand, it reduces the brittleness of the alloy by decreasing the atomic diffusion rate and increasing the stability of the β-phase; on the other hand, during melt solidification, the generated NiAl phase acts as a crystallization nucleus, refining the grains and distributing on the matrix, hindering dislocation movement, thus improving the alloy's strength, hardness, and wear resistance.

[0024] Adding chromium to an alloy system promotes the dispersed precipitation of hard phases, effectively increasing the resistance to dislocation movement and significantly enhancing its hardness and wear resistance, thus maintaining excellent surface integrity under high-load friction environments. Regarding corrosion resistance, chromium spontaneously forms a highly chemically stable, dense passivating oxide film (such as Cr2O3) on the alloy surface. This film effectively blocks the penetration of corrosive media, greatly improving the alloy's resistance to chemical corrosion and marine environments. Furthermore, chromium refines grain size by reducing grain size and increasing grain boundary area, promoting a uniform distribution of strengthening phases and further enhancing the alloy's overall mechanical properties. In terms of processing performance, chromium can precisely control the solidification range during casting, reducing casting defects such as shrinkage cavities and cracks, and improving the alloy's forming quality and processing accuracy.

[0025] The addition of rare earth element Y (yttrium) plays a crucial role in microstructure optimization. Trace amounts of Y can shorten the solidification range and reduce the tendency for solidification cracks, thereby improving casting performance. Furthermore, as an external crystal nucleus, Y promotes the increase of crystallization nuclei, effectively refining the grain structure. The refined grain structure increases the number of grain boundaries, thus enhancing their hindering effect on dislocations, significantly improving the alloy's strength and toughness. It also forms a protective film at the matrix interface, effectively preventing external corrosive media from contacting the matrix, thereby significantly improving the alloy's corrosion resistance in harsh environments such as marine and chemical plants.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows: 1) Innovative Alloy Composition: This invention increases the Mn content to 20%~35%, significantly enhancing the solid solution strengthening effect, greatly improving the strength and hardness of the alloy, while also possessing excellent processing and casting properties, and outstanding mechanical properties, especially in terms of wear resistance and corrosion resistance; increasing the Ni content to 10%~14% significantly improves the alloy's resistance to seawater corrosion; controlling the Al content at 5%~7% improves plasticity while ensuring strength; and adding Cr and Y elements leverages the synergistic effect of multi-element alloying. 2) Excellent performance indicators: The alloy products have a tensile strength of up to 585 MPa, a yield strength of up to 296 MPa, a hardness of up to 305 HV, a friction coefficient as low as 0.43, and a corrosion current density as low as 3.95 × 10⁻⁶. -6 A / cm 2 Its overall performance is significantly better than existing technologies; 3) Environmental protection and safety: This invention does not contain toxic elements such as beryllium and lead, and the production process is environmentally friendly and safe, meeting the environmental protection requirements of green manufacturing; 4) Controllable cost: While ensuring high performance, this invention controls the cost of raw materials through reasonable component design, which has significant advantages such as low cost and balanced comprehensive performance, and has good economic benefits and market competitiveness. 5) The wear-resistant and corrosion-resistant high-manganese copper alloy material of the present invention can be widely used in pump bodies, valve bodies, pipes, propellers and other components in marine environments, as well as other occasions with high requirements for wear resistance and corrosion resistance. Attached Figure Description

[0027] Figure 1 These are comparative metallographic structures of Examples 1-4 of the present invention; Figure 2 This is a dimensional diagram of the tensile test sample of the high-manganese copper alloy according to an embodiment of the present invention; Figure 3 This is a comparison curve of the friction coefficients of Examples 1-4 of the present invention; Figure 4 These are two-dimensional wear morphology comparison images of embodiments 1-4 of the present invention; Figure 5 These are three-dimensional wear morphology comparison images of embodiments 1-4 of the present invention; Figure 6 These are electrochemical Nyquist comparison curves of Examples 1-4 of this invention; Figure 7 These are electrochemical Bode comparison curves of Examples 1-4 of the present invention; Figure 8 These are electrochemical polarization comparison curves of Examples 1-4 of the present invention. Detailed Implementation

[0028] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be construed as limiting the scope of protection of the present invention, but should be understood as a more detailed description of specific aspects, technical features, and implementation schemes of the present invention, intended to enable those skilled in the art to more clearly understand the technical concept and implementation path of the present invention.

[0029] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the specific embodiments used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the specific embodiments described below are some embodiments of the present invention. For those skilled in the art, other specific embodiments can be obtained based on these specific embodiments without creative effort. The components of the embodiments of the present invention described and shown in the specific embodiments herein can typically be arranged and designed in many different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the specific embodiments is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the invention.

[0030] Unless otherwise expressly stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Although this invention specifically describes preferred embodiments and materials, in actual implementation or performance testing of this invention, any technical solutions and materials similar to or equivalent to those described herein may be used without departing from the technical spirit of this invention. All documents referenced in this specification are incorporated herein by reference for the purpose of disclosing and describing the technical methods and / or materials related to those documents; in the event of any conflict between the content of the incorporated documents and this specification, the description in this specification shall prevail.

[0031] Without departing from the scope and spirit of this invention, those skilled in the art can make various improvements and adjustments to the specific embodiments described in this specification, and such modifications and changes are obvious to those skilled in the art. Furthermore, other embodiments derived from this specification also fall within the scope of knowledge that those skilled in the art can clearly understand. Therefore, this specification and the listed embodiments are merely exemplary and not intended to limit the scope of protection of this invention.

[0032] The terms “comprising,” “including,” “having,” and “containing” used in this document are all open-ended expressions, meaning “including but not limited to”, and do not exclude other technical features, components, or steps not explicitly listed.

[0033] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

[0034] In the following embodiments, a graphite crucible with a diameter of 110 mm, a height of 200 mm, and a loading capacity of 15-17 kg is used as an example. Phosphor bronze is a Cu-P master alloy with a P content of 8 wt.%, and its dosage is 1% to 2% of the total alloy mass. The residual P element in the molten metal is no more than 0.1%. Cryolite has the molecular formula Na3AlF6 and its dosage is 0.2% to 0.4% of the total alloy mass. Charcoal powder is composed of C and its dosage is 0.4% to 0.6% of the total alloy mass. The raw materials are any two or more combinations of pure nickel plates, pure copper plates, pure aluminum blocks, pure manganese sheets, Cu-Cr master alloy with a Cr content of 10 wt.%, and Cu-Y master alloy with a Y content of 15 wt.%. The purity of the pure nickel plates, pure copper plates, pure aluminum blocks, and pure manganese sheets is above 99%. In step 1 of the embodiment, the surface treatment method is to use an angle grinder or a shot blasting machine to remove the thick oxide scale and rust layer on the surface of the raw material, and then put the raw material into an oven at 150°C to dry for at least 1 hour to remove the moisture adsorbed on the surface of the raw material. Example 1

[0035] This invention discloses a method for preparing a wear-resistant and corrosion-resistant high-manganese copper alloy, which specifically includes the following steps: 1) Ingredients: Prepare raw materials according to the composition ratio. Based on a total alloy weight of 10kg, Example 1 requires 1kg of pure nickel plate, 0.5kg of pure aluminum block, 2kg of pure manganese sheet, and 6.5kg of pure copper plate. Clean the surfaces. The burn-off ratio of each element is calculated according to conventional methods. The required additional amount is not included in the total weight of the alloy ingredients. 2) Smelting: Place all nickel plates and copper plates into a crucible, sprinkle 30g of cryolite flux and 50g of charcoal powder covering agent on the surface, then heat to 1300~1350℃. After observing the molten metal, add all manganese flakes and stir with a stirring rod to fully melt it. After it is completely melted, add 75g of phosphorus copper for the first degassing. After observing that the gas has completely escaped, keep it at the temperature for 10 minutes, then add all aluminum blocks. After the aluminum blocks are completely melted, add 50g of phosphorus copper again for the second degassing. After the gas is completely removed, keep it at the temperature for 10 minutes, and then remove the slag to obtain the molten metal. 3) Casting: Molten metal at a temperature of 1250~1300℃ is poured into a metal mold to obtain a copper alloy ingot; 4) Solution treatment: The copper alloy ingot is solution treated at a temperature of 950-980℃ for 2-3 hours. The cooling method is water cooling to room temperature to obtain a wear-resistant and corrosion-resistant high-manganese copper alloy. Example 2

[0036] This invention discloses a method for preparing a wear-resistant and corrosion-resistant high-manganese copper alloy, which specifically includes the following steps: 1) Ingredients: Prepare raw materials according to the composition ratio. Based on a total weight of 10kg, Example 2 requires 1kg of pure nickel plate, 0.5kg of pure aluminum block, 3kg of pure manganese sheet, and 5.5kg of pure copper plate. Clean the surfaces. The burn-off ratio of each element is calculated according to conventional methods. The required additional amount is not included in the total weight of the alloy ingredients. 2) Smelting: Place all nickel plates and copper plates into a crucible, sprinkle 35g of cryolite flux and 55g of charcoal powder covering agent on the surface, then heat to 1320~1340℃. After observing the molten metal, add all manganese flakes and stir with a stirring rod to fully melt it. After complete melting, add 80g of phosphorus copper for the first degassing. After observing that the gas has completely escaped, keep it at the temperature for 10 minutes, then add all aluminum blocks. After the aluminum blocks have completely melted, add 50g of phosphorus copper again for the second degassing. After the gas is completely removed, keep it at the temperature for 10 minutes, and then remove the slag to obtain the molten metal. 3) Casting: Molten metal at a temperature of 1250~1300℃ is poured into a metal mold to obtain a copper alloy ingot; 4) Solution treatment: The copper alloy ingot is solution treated at a temperature of 910-940℃ for 2-3 hours. The cooling method is water cooling to room temperature to obtain a wear-resistant and corrosion-resistant high-manganese copper alloy. Example 3

[0037] This invention discloses a method for preparing a wear-resistant and corrosion-resistant high-manganese copper alloy, which specifically includes the following steps: 1) Ingredients: Prepare raw materials according to the composition ratio. Based on a total weight of 10kg, Example 3 requires 1.4kg of pure nickel plate, 0.7kg of pure aluminum block, 3.5kg of pure manganese sheet, and 4.4kg of pure copper plate. Clean the surfaces. The burn-off ratio of each element is calculated according to conventional methods. The required additional amount is not included in the total weight of the alloy ingredients. 2) Smelting: Place all nickel plates and copper plates into a crucible, sprinkle 30g of cryolite flux and 50g of charcoal powder covering agent on the surface, then heat to 1300~1320℃. After observing the molten metal, add all manganese flakes and stir with a stirring rod to fully melt it. After it is completely melted, add 80g of phosphorus copper for the first degassing. After observing that the gas has completely escaped, keep it at the temperature for 10 minutes, then add all aluminum blocks. After the aluminum blocks are completely melted, add 50g of phosphorus copper again for the second degassing. After the gas is completely removed, keep it at the temperature for 10 minutes, and then remove the slag to obtain the molten metal. 3) Casting: Molten metal at a temperature of 1250~1300℃ is poured into a metal mold to obtain a copper alloy ingot; 4) Solution treatment: The copper alloy ingot is solution treated at a temperature of 900-930℃ for 2-3 hours. The cooling method is water cooling to room temperature to obtain a wear-resistant and corrosion-resistant high-manganese copper alloy. Example 4

[0038] This invention discloses a method for preparing a wear-resistant and corrosion-resistant high-manganese copper alloy, which specifically includes the following steps: 1) Ingredients: Prepare raw materials according to the component ratio. Calculated based on a total weight of 10kg, Example 4 requires 1.4kg of pure nickel plate, 0.7kg of pure aluminum block, 3.5kg of pure manganese sheet, 1kg of Cu-Cr master alloy with 10wt.% Cr content, 0.333kg of Cu-Y master alloy with 15wt.% Y content, and 3.067kg of pure copper plate. Clean the surfaces. The burn-off ratio of each element is calculated according to conventional methods, and the required increase is not included in the total weight of the alloy ingredients. 2) Smelting: Place all nickel plates and copper plates into a crucible, sprinkle 40g of cryolite flux and 60g of charcoal powder covering agent on their surface, then heat to 1305~1335℃. After observing the molten metal, add all manganese flakes and stir with a stirring rod to fully melt it. After complete melting, add 85g of phosphorus copper for the first degassing. After observing that the gas has completely escaped, add Cu-Cr master alloy with a Cr content of 10wt.%, hold for 10 minutes, and then add all aluminum blocks. After the aluminum blocks have completely melted, add 55g of phosphorus copper again for the second degassing. After the gas is completely removed, add Cu-Y master alloy with a Y content of 15wt.%, hold for 10 minutes, and then remove the slag to obtain molten metal. 3) Casting: Molten metal at a temperature of 1250~1300℃ is poured into a metal mold to obtain a copper alloy ingot; 4) Solution treatment: The copper alloy ingot is solution treated at a temperature of 920-960℃ for 2-3 hours. The cooling method is water cooling to room temperature to obtain a wear-resistant and corrosion-resistant high-manganese copper alloy.

[0039] Comparative Example 1 Production unit: Luoyang Copper Processing Group Co., Ltd. (Chinalco Luoyang Copper); Specifications: QMn5 (annealed state, conforming to GB / T 5231-2022 "Copper and Copper Alloys Grades and Chemical Compositions" standard); Applicable scenarios: Conventional mechanical wear-resistant parts, conductive wear-resistant components, and industrial basic high-manganese copper alloy; Mechanical properties: tensile strength 420 MPa, yield strength 185 MPa, elongation 22.5%, hardness 135 HV.

[0040] Comparative Example 2 Manufacturer: Zhejiang Hailiang Co., Ltd. Specifications: ZQMnD12-8-3-2 (cast condition, conforming to GB / T 1176-2013 "Cast Copper Alloys" standard); Applicable scenarios: conventional wear-resistant parts for marine engineering, low-speed bushings for ships, representing the high-manganese copper alloy grade for marine applications in the existing technology; Mechanical properties: tensile strength 480 MPa, yield strength 210 MPa, elongation 8%, hardness 205 HV.

[0041] Comparative Example 3 Production unit: Jiangsu University; Specifications: A strontium, titanium and boron composite microalloyed high manganese aluminum bronze (wherein Sr: 0.012~0.047wt.%, Ti: 0.028~0.073wt.%, B: 0.006~0.015wt.%, Mn: 8.0~20wt.%, Al: 6.5~9.0wt.%, Fe: 2.0~5.0wt.%, Ni: 1.5~3.0wt.%, Zn≤6wt.%) Applicable scenarios: propellers of large marine vessels, seawater pumps, offshore oil platforms, seawater pipeline systems, etc. Performance indicators: Hardness 215.1 HV, uniform corrosion rate 0.02335 mm / a, wet friction coefficient in 3.5% NaCl solution when rubbed against Si3N4 (silicon nitride) ball.

[0042] The high-manganese copper alloy samples prepared in Examples 1-4 above were tested for hardness, tensile strength, yield strength, elongation, wear resistance and corrosion resistance, respectively.

[0043] Hardness tests were conducted according to GB / T 4340.1-2009: "Metallic materials - Vickers hardness test - Part 1: Test method". An HXS-1000A digital intelligent microhardness tester was used to measure the hardness, with a load F of 0.5 kgf and a holding time T of 10 s. At least nine points were uniformly marked on each sample to obtain hardness values. The highest and lowest hardness values ​​were discarded, and the average value of the remaining points was calculated.

[0044] Tensile tests were conducted according to GB / T 228.1-2010: Metallic materials, tensile testing—Part 1: Tests at room temperature. A universal electronic tensile testing machine was used for the tensile property testing. The dimensions of the tensile test samples are as follows: Figure 1 As shown, the selected tensile speed was 0.5 mm / min, and at least three parallel samples were used for testing in each group of samples under different conditions. The yield strength σ was measured. s Tensile strength σ b Elongation δ is used as an indicator to judge the strength and plasticity of an alloy.

[0045] Friction and wear tests were conducted according to GB / T 12444.2-2009: Multi-step loading wear test method for metallic materials - Part 2: Ball wear test. Friction and wear tests were performed on a MWF-02 rotary reciprocating friction and wear testing machine. The specimen size was a block specimen of 15 mm × 15 mm × 15 mm. The friction ball was a 6 mm diameter GCr15 steel ball (HRC61-63). Fixed speed, load, and time conditions were applied. The test temperature was room temperature (25℃), the load was 30 N, the test time was 3600 s, and the reciprocating frequency was 1 Hz. The coefficient of friction (COF) value was obtained. After grinding, the wear morphology was analyzed using a laser confocal microscope to evaluate its wear resistance.

[0046] Electrochemical corrosion tests were conducted according to GB / T 18593.1-2001: Corrosion of Metals and Alloys – Corrosion of Copper Alloys – Part 1: Determination of Mass Loss Due to Uniform Corrosion. A CS350M electrochemical workstation was used, and electrochemical experiments were performed in a 3.5 wt.% NaCl solution. In this study, a saturated calomel electrode (SCE) was used as the reference electrode, a platinum electrode as the auxiliary electrode, and the research material as the working electrode in the three-electrode system. The test sequence was: measurement of self-corrosion potential, electrochemical impedance spectroscopy, and polarization curve testing to evaluate its corrosion resistance.

[0047] Before conducting electrochemical tests, to measure the self-corrosion potential of the sample electrode, the test sample was first placed in a 3.5 wt.% NaCl solution and allowed to stand for 30 min to stabilize its open-circuit potential. Subsequently, the open-circuit potential was measured within a range of ±1 V at a scan rate of 0.2 mV / s. When the potential fluctuation was less than 0.5 mV per min, the test system was considered to have reached a steady state, and this potential was considered the self-corrosion potential.

[0048] When performing electrochemical impedance spectroscopy, the sampling frequency range is 10. -2 Hz-10 5 The test was conducted at Hz, with an AC sine wave amplitude of 10mV and a test temperature of 25℃. The measured data were analyzed and fitted using ZSimpWin software. During polarization curve testing, the scan range was -0.5 V to 0.8 V, and the scan rate was 0.5 mV / s. The Tafel curves were fitted and analyzed using the built-in analysis system of the electrochemical workstation to obtain the self-corrosion potential (Ecorr) and self-corrosion current (Icorr).

[0049] The composition and mechanical properties of the high-manganese copper alloys obtained in Examples 1-4 are shown in Tables 1 and 2, respectively.

[0050] Table 1. Examples of the composition of wear-resistant and corrosion-resistant high-manganese copper alloys / wt.% Table 2 Mechanical properties of wear-resistant and corrosion-resistant high-manganese copper alloys The test results of the friction and corrosion properties of the high-manganese copper alloys obtained in Examples 1-4 are shown in Table 3.

[0051] Table 3. Friction and corrosion properties of wear-resistant and corrosion-resistant high-manganese copper alloys Comparative metallographic microstructure photographs of the high-manganese copper alloys obtained in Examples 1-4 are shown below. Figure 1 The shapes and dimensions of the tensile test specimens for the alloys in each embodiment are shown in the figure. Figure 2 .

[0052] The friction coefficient curves of the alloys in each embodiment are shown in the figure. Figure 3 It can be seen that with the addition of alloying elements, the coefficient of friction of the alloy gradually decreases, and its wear resistance is enhanced.

[0053] The two-dimensional wear cross-sectional morphology of the alloys in each embodiment is shown in the figure. Figure 4 It can be seen that with the addition of alloying elements, the wear depth of the alloy gradually decreases, and its wear resistance is enhanced.

[0054] The three-dimensional wear morphology of the alloys in each embodiment is shown in the figure. Figure 5 It can be seen that with the addition of alloying elements, the wear depth of the alloy gradually decreases, and its wear resistance is enhanced.

[0055] The electrochemical Nyquist curves of the alloys in each embodiment are shown below. Figure 6 It can be seen that with the addition of alloying elements, the impedance of the alloy gradually increases, and its corrosion resistance is enhanced.

[0056] The electrochemical Bode curves of the alloys in each embodiment are shown below. Figure 7 It can be seen that with the addition of alloying elements, the modulus diagram and phase diagram of the alloy gradually increase, and the corrosion resistance is enhanced.

[0057] The electrochemical polarization curves of the alloys in each embodiment are shown in the figure. Figure 8 It can be seen that with the addition of alloying elements, the self-corrosion potential of the alloy gradually increases, the corrosion current density gradually decreases, and the corrosion resistance is enhanced.

[0058] The technical means disclosed in this invention are not limited to those disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications are also considered within the scope of protection of this invention.

Claims

1. A wear-resistant and corrosion-resistant high-manganese copper alloy, characterized in that: The composition of the material by weight percentage (wt.%) is as follows: Mn: 20%~35%, Al: 5%~7%, Ni: 10%~14%, with the balance being Cu and unavoidable impurities. The total percentage of all impurities is no more than 0.5%, and the content of any one of Pb, Sn, Si, Zn, P, and S is no more than 0.1%.

2. The method for preparing a wear-resistant and corrosion-resistant high-manganese copper alloy according to claim 1, characterized in that: Specifically, the following steps are included: 1) Ingredient preparation: Prepare raw materials according to the component ratio and clean the surfaces; 2) Smelting: Place the nickel plate and copper plate in a crucible, sprinkle the flux cryolite and the covering agent charcoal powder on their surface, then heat to 1300~1350℃. After observing the molten metal, add manganese flakes and stir with a stirring rod to make it fully melted. After it is completely melted, add phosphor bronze for the first degassing. After observing that the gas has completely escaped, keep it at the temperature for 10 minutes, then add aluminum blocks. After the aluminum blocks are completely melted, add phosphor bronze again for the second degassing. After the gas is completely removed, keep it at the temperature for 10 minutes, and then remove the slag to obtain the molten metal. 3) Casting: Molten metal at a temperature of 1250~1300℃ is poured into a metal mold to obtain a copper alloy ingot; 4) Solution treatment: After solution treatment of the copper alloy ingot, wear-resistant and corrosion-resistant high-manganese copper alloy is obtained.

3. A wear-resistant and corrosion-resistant high-manganese copper alloy, characterized in that: The composition of the material by weight percentage (wt.%) is as follows: Mn: 20%~35%, Al: 5%~7%, Ni: 10%~14%, Cr: 0.6%~1.5%, Y: 0.2%~1%, with the balance being Cu and unavoidable impurities. The total percentage of all impurities is no more than 0.5%, and the content of any one of Pb, Sn, Si, Zn, P, and S is no more than 0.1%.

4. The method for preparing a wear-resistant and corrosion-resistant high-manganese copper alloy according to claim 3, characterized in that: Specifically, the following steps are included: 1) Ingredient preparation: Prepare raw materials according to the component ratio and clean the surfaces; 2) Smelting: Place the nickel plate and copper plate in a crucible, sprinkle the flux cryolite and the covering agent charcoal powder on their surface, and then heat to 1300~1350℃. After observing the molten metal, add manganese flakes and stir with a stirring rod to make it fully melted. After it is completely melted, add phosphor bronze for the first degassing. After observing that the gas has completely escaped, add Cu-Cr master alloy with a Cr content of 10wt.%, hold for 10 minutes, and then add aluminum blocks. After the aluminum blocks are completely melted, add phosphor bronze again for the second degassing. After the gas is completely removed, add Cu-Y master alloy with a Y content of 15wt.%, hold for 10 minutes, and then remove the slag to obtain the molten metal. 3) Casting: Molten metal at a temperature of 1250~1300℃ is poured into a metal mold to obtain a copper alloy ingot; 4) Solution treatment: After solution treatment of the copper alloy ingot, wear-resistant and corrosion-resistant high-manganese copper alloy is obtained.

5. A method for preparing a wear-resistant and corrosion-resistant high-manganese copper alloy material according to claim 2 or 4, characterized in that: The phosphor bronze is a Cu-P master alloy with a P content of 8 wt.%, and the amount used is 1% to 2% of the total alloy mass. The residual P element in the molten metal is no more than 0.1%.

6. A method for preparing a wear-resistant and corrosion-resistant high-manganese copper alloy material according to claim 2 or 4, characterized in that: The cryolite has the molecular formula Na3AlF6 and is used in an amount of 0.2% to 0.4% of the total alloy mass; the charcoal powder is composed of carbon and is used in an amount of 0.4% to 0.6% of the total alloy mass.

7. A method for preparing a wear-resistant and corrosion-resistant high-manganese copper alloy material according to claim 2 or 4, characterized in that: The solution treatment temperature in step 4) is 900-980℃, the holding time is 2-3 hours, and the cooling method is water cooling to room temperature.

8. A method for preparing a wear-resistant and corrosion-resistant high-manganese copper alloy material according to claim 2 or 4, characterized in that: In step 1), the raw materials are any two or more combinations of pure nickel plates, pure copper plates, pure aluminum blocks, pure manganese sheets, Cu-Cr master alloy with a Cr content of 10 wt.% and Cu-Y master alloy with a Y content of 15 wt.%, and the purity of the pure nickel plates, pure copper plates, pure aluminum blocks and pure manganese sheets is 99% or higher.

9. A method for preparing a wear-resistant and corrosion-resistant high-manganese copper alloy material according to claim 2 or 4, characterized in that: The surface treatment method in step 1) is to grind with an angle grinder or clean with a shot blasting machine to remove the thick oxide scale and rust layer on the surface of the raw material, and then put the raw material into an oven at 150°C to dry for at least 1 hour to remove the moisture adsorbed on the surface of the raw material.

10. A wear-resistant and corrosion-resistant high-manganese copper alloy material according to claim 1 or 3, characterized in that: The wear-resistant and corrosion-resistant high-manganese copper alloy has a tensile strength of up to 585 MPa, a yield strength of up to 296 MPa, a hardness of up to 305 HV, a friction coefficient as low as 0.43, and a corrosion current density as low as 3.95 × 10⁻⁶. -6 A / cm 2 .

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