High-strength corrosion-resistant CuNi10Fe1Mn alloy copper pipe and preparation method thereof

Abstract

The embodiment of the invention discloses a high-strength corrosion-resistant CuNi10Fe1Mn alloy copper pipe and a preparation method thereof, relates to the technical field of non-ferrous metal material manufacturing, and aims to solve the technical problem of poor production in the prior art. According to the high-strength corrosion-resistant CuNi10Fe1Mn alloy copper pipe, the content of Ni ranges from 9.0% to 11.0%, the content of Fe ranges from 1.0% to 2.0%, the content of Mn ranges from 0.5% to 1.0%, the sum of impurity elements does not exceed 0.2%, and the balance is Cu.

Description

Technical Field

[0001] The present application relates to the technical field of nonferrous metal material manufacturing, and in particular to a high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube and a preparation method thereof. Background Art

[0002] Copper-nickel alloy tube is an alloy tube made of copper and nickel in a specific proportion. The alloy tube exhibits unique physical and chemical properties: first, it has excellent corrosion resistance and can resist erosion by a variety of corrosive media including seawater, acidic and alkaline solutions. This is mainly due to the addition of nickel, which significantly improves the stability of the alloy in harsh environments. Secondly, copper-nickel alloy tubes have high tensile strength and yield strength and can withstand greater mechanical stress and pressure. Finally, the alloy tube has good weldability and machinability. It can be formed through a variety of processing methods such as cold working and hot working, and can be welded with other materials to form complex structures to ensure the integrity of integrated components.

[0003] In view of the high strength, excellent thermal conductivity and excellent corrosion resistance of copper-nickel alloy tubes, they have been widely used in the fields of condenser tubes, heat exchanger tubes, condenser plates, distiller tubes, evaporators, ferrules, salt water pipelines, ship hull structures, etc. in thermal power, shipbuilding, seawater desalination and other industries. In the prior art, the production of copper-nickel alloy tubes mainly adopts the process of "semi-continuous casting solid ingot → hot extrusion tube billet → semi-finished product stretching (or cold rolling) → finished product stretching", referred to as the "extrusion-rolling" method. However, there are several problems with this process: high equipment investment cost, numerous stretching / cold rolling passes, a large environmental load caused by the pickling process, a lengthy process, high energy consumption, low yield, and high cost. In addition, due to the high nickel content during high-temperature extrusion of the tube billet, serious metal oxidation, mold sticking, eccentric tube billet scrapping and other problems occur, which seriously limit the larger-scale industrial application of copper-nickel alloy tubes. Summary of the invention

[0004] The main purpose of the present application is to provide a high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube and a preparation method thereof, aiming to solve the technical problems of poor production in the prior art.

[0005] To achieve the above objectives, the technical solutions adopted in the embodiments of the present application are as follows:

[0006] In a first aspect, an embodiment of the present application provides: a high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube, wherein the CuNi10Fe1Mn alloy copper tube has a Ni content of 9.0%-11.0%, a Fe content of 1.0%-2.0%, a Mn content of 0.5%-1.0%, a total impurity element content of no more than 0.2%, and the remainder is Cu.

[0007] As some optional embodiments of the present application, among the impurity elements, C content ≤0.05%, Co content ≤0.1%, P content ≤0.02%, Pb content ≤0.02%, S content ≤0.05%, Sn content ≤0.03%, and Zn content ≤0.5%.

[0008] As some optional embodiments of the present application, the average grain size of the CuNi10Fe1Mn alloy copper tube is ≤50 μm.

[0009] As some optional embodiments of the present application, the tensile strength of the CuNi10Fe1Mn alloy copper tube is ≥340MPa.

[0010] As some optional embodiments of the present application, the yield strength of the CuNi10Fe1Mn alloy copper tube is ≥120MPa.

[0011] As some optional implementations of the present application, the elongation of the CuNi10Fe1Mn alloy copper tube is ≥35%.

[0012] As some optional embodiments of the present application, the hardness of the CuNi10Fe1Mn alloy copper tube is ≥75HRF.

[0013] In a second aspect, the present application also provides: a method for preparing a high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube, comprising the following steps:

[0014] Smelting is performed according to the following content percentages: Ni content is 9.0%-11.0%, Fe content is 1.0%-2.0%, Mn content is 0.5%-1.0%, the total amount of impurity elements does not exceed 0.2%, and the balance is Cu; among the impurity elements, C content is ≤0.05%, Co content is ≤0.1%, P content is ≤0.02%, Pb content is ≤0.02%, S content is ≤0.05%, Sn content is ≤0.03%, and Zn content is ≤0.5%; obtaining an alloy melt;

[0015] The alloy melt is subjected to horizontal continuous casting treatment, and then sequentially subjected to planetary rolling treatment, cold drawing treatment and annealing treatment to obtain a high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube.

[0016] As some optional embodiments of the present application, the temperature of the horizontal continuous casting process is 1200°C

[0017] -1300°C, assisted by electromagnetic stirring, the electromagnetic stirring rate is 2000r / min-3000r / min;

[0018] The planetary rolling process refers to a process of rolling through a three-roll mill or a four-roll mill to achieve a deformation of 30%-90%; the temperature of the planetary rolling process is 700-800°C, the speed of the planetary rolling process is 5-30m / min, and the atmosphere protection is a H2-N2 mixed atmosphere.

[0019] As some optional embodiments of the present application, the applied deformation amount of the cold drawing process is 20%-50%, and the number of cold drawing processes is 1-4 times;

[0020] The annealing treatment refers to an annealing treatment performed at a temperature of 400° C. to 500° C. for 1 h to 2 h, and nitrogen or argon is used for atmosphere protection during the annealing treatment.

[0021] Compared with the prior art, the present application has successfully developed a CuNi10Fe1Mn alloy copper tube with both high strength and excellent corrosion resistance by carefully adjusting the material ratio of the alloy copper tube. In the chemical composition of the alloy copper tube, the content of nickel (Ni) is precisely controlled within the range of 9.0% to 11.0%, the content of iron (Fe) is between 1.0% and 2.0%, and the content of manganese (Mn) is between 0.5% and 1.0%. In addition, the sum of impurity elements is strictly limited to no more than 0.2% to ensure the purity of the alloy, and the remaining part is copper (Cu). In the Cu-Ni alloy system, the solid solubility of iron (Fe) is relatively low. For example, at a high temperature of 950°C, the solid solubility of iron can reach 4.8%, but when the temperature drops to 300°C, its solid solubility drops significantly to 0.1%. The addition of iron (Fe) has a significant effect on improving the corrosion resistance and mechanical properties of Cu-Ni alloys, especially in enhancing the ability of the alloy to resist seawater impact corrosion. However, it should be noted that if the iron (Fe) content in the Cu-Ni-Fe alloy exceeds 2%, the alloy is prone to stress corrosion cracking; if the content further exceeds 4%, the corrosion phenomenon will be aggravated. On the other hand, manganese (Mn) can form MnNi compounds in the Cu-Ni-Mn alloy, which improves the overall strength, corrosion resistance and elasticity of the alloy through precipitation hardening effect. In addition, manganese (Mn) can also enhance the ability of Cu-Ni alloy to resist turbulent impact corrosion. Although it will slightly reduce the stress corrosion cracking resistance of B19 alloy, its negative impact is much less than that of other elements such as aluminum (Al), silicon (Si), tin (Sn), chromium (Cr), and beryllium (Be). At the same time, manganese (Mn) can also eliminate the negative impact of excessive carbon in Cu-Ni alloy, thereby improving the process performance of the alloy. It can be seen that the present application has excellent mechanical properties through reasonable alloy element ratio and heat treatment process, and can withstand heavy loads and complex stress environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A metallographic diagram of a cross section involved in an embodiment of the present application;

[0023] Figure 2 This is a metallographic diagram of the longitudinal section involved in the embodiment of the present application. DETAILED DESCRIPTION

[0024] It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0025] In the current technical field, copper tubes often show insufficient corrosion resistance and reduced mechanical properties when encountering complex environmental conditions, such as corrosive media such as seawater and chlorides. The existence of these problems seriously limits the scope of use of copper tubes in specific application fields. Therefore, developing a copper tube product with both high strength and excellent corrosion resistance is of great significance to expand its application in related fields.

[0026] Copper-nickel alloy tubes are alloy tubes made of copper (Cu) and nickel (Ni) in a certain proportion. This alloy tube exhibits unique physical and chemical properties: (1) Corrosion resistance: Copper-nickel alloy tubes have excellent corrosion resistance and can effectively resist the erosion of various corrosive media including seawater, acidic and alkaline solutions. This feature is mainly due to the addition of nickel, which significantly enhances the stability of the alloy in harsh environments. (2) High strength: Compared with pure copper tubes or other alloy tubes, copper-nickel alloy tubes have higher tensile strength and yield strength and can withstand greater mechanical stress and pressure. (3) Good weldability and machinability: Copper-nickel alloy tubes are easy to form through various processing methods (such as cold processing, hot processing, etc.), and can be welded with other materials to form complex structures to ensure the integrity of integrated components.

[0027] Due to its high strength, excellent thermal conductivity and corrosion resistance, copper-nickel alloy tubes are widely used in condensers, heat exchanger tubes, condenser plates, distiller tubes, evaporators, ferrules, salt water pipes, ship hull structures, etc. in the fields of thermal power, ships, and seawater desalination.

[0028] The main process flow for producing copper-nickel alloy pipes is "semi-continuous casting solid ingot → hot extrusion tube billet → semi-finished product stretching (or cold rolling) → finished product stretching", referred to as the "extrusion-rolling" method. The main challenges faced by this process include: high equipment investment, multiple stretching / cold rolling processes, pickling processes with heavy environmental loads, long process flow, high energy consumption, low yield and high cost. In addition, due to the high nickel content during high-temperature extrusion of tube billets, serious metal oxidation, mold sticking, eccentric tube billet scrapping and other problems occur, which seriously limit its potential for larger-scale industrial applications.

[0029] Horizontal continuous casting (replacing semi-continuous casting → hot extrusion) → cold rolling / drawing is the key way to solve the above problems. In recent years, the "horizontal continuous casting-external surface milling → planetary rolling / cold rolling and drawing" process for the production of copper and copper alloy tubes has been developed. Although horizontal continuous casting can simplify the production process of tube billets, reduce energy consumption, and improve production efficiency, the produced tube billets mainly have the following two problems: (1) The inner and outer surface quality of the cast tube is poor, with surface defects such as orange peel, wrinkles, and cracks. This requires surface milling before subsequent processing steps, which increases the processing steps and reduces the product yield. In addition, the casting defects on the internal surface are difficult to effectively eliminate, which seriously affects the quality of the final product. (2) The cast tube is composed of columnar grains in the radial direction, which is not conducive to the axial expansion deformation of subsequent cold processing (rolling and drawing).

[0030] Based on the above technical problems, an embodiment of the present application proposes a high-strength and corrosion-resistant CuNi10Fe1Mn alloy copper tube, in which the Ni content of the CuNi10Fe1Mn alloy copper tube is 9.0%-11.0%, the Fe content is 1.0%-2.0%, the Mn content is 0.5%-1.0%, the total impurity elements do not exceed 0.2%, and the balance is Cu; among the impurity elements, the C content is ≤0.05%, the Co content is ≤0.1%, the P content is ≤0.02%, the Pb content is ≤0.02%, the S content is ≤0.05%, the Sn content is ≤0.03%, and the Zn content is ≤0.5%.

[0031] The present application has successfully developed a CuNi10Fe1Mn alloy copper tube with both high strength and excellent corrosion resistance by carefully adjusting the material ratio of the alloy copper tube. In the chemical composition of the alloy copper tube, the content of nickel (Ni) is precisely controlled within the range of 9.0% to 11.0%, the content of iron (Fe) is between 1.0% and 2.0%, and the content of manganese (Mn) is between 0.5% and 1.0%. In addition, the sum of impurity elements is strictly limited to no more than 0.2% to ensure the purity of the alloy, and the remaining part is copper (Cu). In the Cu-Ni alloy system, the solid solubility of iron (Fe) is relatively low. For example, at a high temperature of 950°C, the solid solubility of iron can reach 4.8%, but when the temperature drops to 300°C, its solid solubility drops significantly to 0.1%. The addition of iron (Fe) has a significant effect on improving the corrosion resistance and mechanical properties of Cu-Ni alloys, especially in enhancing the ability of the alloy to resist seawater impact corrosion. However, it should be noted that if the iron (Fe) content in the Cu-Ni-Fe alloy exceeds 2%, the alloy is prone to stress corrosion cracking; if the content further exceeds 4%, the corrosion phenomenon will be aggravated. On the other hand, manganese (Mn) can form MnNi compounds in the Cu-Ni-Mn alloy, which improves the overall strength, corrosion resistance and elasticity of the alloy through precipitation hardening effect. In addition, manganese (Mn) can also enhance the ability of Cu-Ni alloy to resist turbulent impact corrosion. Although it will slightly reduce the stress corrosion cracking resistance of B19 alloy, its negative impact is much less than that of other elements such as aluminum (Al), silicon (Si), tin (Sn), chromium (Cr), and beryllium (Be). At the same time, manganese (Mn) can also eliminate the negative impact of excessive carbon in Cu-Ni alloy, thereby improving the process performance of the alloy. It can be seen that the present application has excellent mechanical properties through reasonable alloy element ratio and heat treatment process, and can withstand heavy loads and complex stress environments.

[0032] That is: the average grain size of the CuNi10Fe1Mn alloy copper tube is ≤50μm, and the tensile strength is

[0033] ≥340MPa, yield strength ≥120MPa, elongation ≥35%, hardness ≥75HRF. It should be noted that the stress corrosion test EN ISO 196 or ISO 6957 and the expansion test GB / T242-2007, as well as the eddy current flaw detection test, are all qualified; the average grain size test standard is EN ISO 2624; the tensile test standard is ISO6892-1:2019; and the eddy current flaw detection test standard is EN 1971.

[0034] In addition, the present application also provides a corresponding preparation method, namely: a preparation method of a high-strength corrosion-resistant CuNi10Fe1Mn alloy copper tube, comprising the following steps:

[0035] Smelting is performed according to the following content percentages: Ni content is 9.0%-11.0%, Fe content is 1.0%-2.0%, Mn content is 0.5%-1.0%, the total amount of impurity elements does not exceed 0.2%, and the balance is Cu; among the impurity elements, C content is ≤0.05%, Co content is ≤0.1%, P content is ≤0.02%, Pb content is ≤0.02%, S content is ≤0.05%, Sn content is ≤0.03%, and Zn content is ≤0.5%; obtaining an alloy melt;

[0036] The alloy melt is subjected to horizontal continuous casting treatment, and then sequentially subjected to planetary rolling treatment, cold drawing treatment and annealing treatment to obtain a high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube. The temperature of the horizontal continuous casting treatment is 1200℃-1300℃, the billet drawing speed is 0.8m / min-3m / min, the billet drawing frequency is 80 times / h-120 times / h, the graphite crystallizer is assisted by electromagnetic stirring treatment, and the electromagnetic stirring rate is 2000r / min-3000r / min; the planetary rolling treatment refers to the use of a three-roll mill or a four-roll mill. The three-roll planetary rolling technology is mature and widely used, and is particularly suitable for the production of metal pipes such as copper pipes and steel pipes; and the four-roll planetary rolling is improved and innovated on this basis, which improves the stability and efficiency of rolling to achieve a deformation of 30%-90%; the applied deformation of the cold drawing treatment is 20%-50%; the annealing treatment refers to annealing treatment at a temperature of 400℃-500℃ for 1h-2h.

[0037] Compared with the existing technology, the preparation method proposed in this application has the following significant advantages:

[0038] (1) This method uses an advanced composite electromagnetic stirring technology, which is combined with the horizontal continuous casting process to produce hollow copper-nickel alloy billets with uniform structure, fine grains and excellent mechanical properties. A notable feature of this method is that during the production process, the billets do not need to undergo any heat treatment before rolling. Specifically, this method improves the equiaxed crystal ratio. Under the action of electromagnetic force, the grains in the liquid metal are disturbed, which promotes the formation of equiaxed crystals and optimizes the microstructure of the billet. In addition, the electromagnetic force also refines the solidification structure of the billet, promotes the uniform distribution of solute elements in the liquid metal, reduces component segregation, and further refines the grains. These factors work together to help homogenize the internal composition of the billet. During the stirring process, the solute elements in the liquid metal are effectively dispersed, reducing local enrichment, thereby improving the overall quality of the billet. Through this technology, we can ensure the quality stability of the billet during the production process and reduce production costs because the heat treatment step is omitted. In addition, since the microstructure of the ingot is optimized, its plasticity and machinability in subsequent processing are also significantly improved, which is of great significance for improving the quality and performance of the final product.

[0039] (2) During the rolling process, the method adopts a three-roll or four-roll planetary rolling mill to roll the ingot with a one-time processing rate of more than 90%. This advanced rolling method can ensure that the processing rate of the ingot can reach more than 90% after one processing, which is a relatively high proportion in the rolling industry. The temperature of the rolling deformation zone is maintained above 800°C. This temperature control strategy can effectively bridge the defects that may occur during the casting process and significantly reduce the rolling deformation resistance of white copper. Such temperature management enables the alloy copper tube to achieve complete recrystallization during the rolling process, thereby optimizing the material properties. This highly efficient rolling process not only greatly improves production efficiency and shortens production cycles, but also ensures the high quality of the final product and meets the market demand for high-quality copper tubes. By adopting this planetary rolling mill, we can achieve efficient processing of the ingot while ensuring the stability and reliability of the processing process. In addition, the use of the planetary rolling mill can also reduce equipment wear and energy consumption, further reducing production costs. During the rolling process, we also pay special attention to the precise control of rolling parameters to ensure that each rolling can achieve the best effect. Through these fine process controls, we are able to produce copper tube products with excellent performance, which not only excel in mechanical properties, but also reach the industry-leading level in corrosion resistance and conductivity.

[0040] (3) Adopting atmosphere protection technology inside the rolling mill, such as using a mixed atmosphere of hydrogen and nitrogen, can effectively ensure that the inner and outer surfaces of the white copper rolled tube remain bright and will not undergo oxidation reaction, thus facilitating the forming process of the rolled tube. Through this protection measure, the oxidation phenomenon of the rolled tube during the processing can be significantly prevented, thereby ensuring that there will be no undesirable phenomena such as cracks and stratification inside the rolled tube, which not only improves the yield rate, but also ensures the high quality and good appearance of the product. In addition, the application of this atmosphere protection technology can also reduce energy consumption during the rolling process, because it can reduce the friction coefficient during rolling, thereby reducing energy consumption. At the same time, due to the presence of the protective atmosphere, the rolled tube can obtain a more uniform temperature distribution during the processing process, which helps to improve the dimensional accuracy and surface quality of the rolled tube. Therefore, the atmosphere protection technology not only plays an important role in preventing oxidation, but also has a significant effect in improving production efficiency, saving energy and improving product quality.

[0041] (4) After annealing, we found that the mechanical properties and grain structure of the material were significantly improved. The annealing process actually plays a very critical role. It helps to eliminate various stresses inside the material and optimizes the grain structure. Such treatment can not only further improve the comprehensive performance of the material, but also ensure the reliability and durability of the final product, so that the product can show better performance in practical applications. Through annealing, the microstructure of the material is adjusted, making the grain size more uniform and reducing grain boundary defects, thereby improving the toughness, strength and plasticity of the material. In addition, the annealing process can also improve the electrical and magnetic properties of the material, making it more widely used in the field of electronic and magnetic materials. Therefore, annealing is an indispensable step in materials science and is of great significance for improving the performance of materials and broadening their application range.

[0042] To facilitate those skilled in the art to understand the technical solution of the present application, the method described in the present application is described in detail below in conjunction with specific embodiments:

[0043] Example 1

[0044] A method for preparing a high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube comprises the following steps:

[0045] The following percentages are used for smelting: Ni content is 9.78%, Fe content is 1.33%, Mn content is 0.72%, the total amount of impurity elements does not exceed 0.2%, and the balance is Cu; among the impurity elements, C content is 0.006%, Co content is 0.003%, P content is 0.005%, Pb content is 0.008%, S content is 0.005%, Sn content is 0.009%, and Zn content is 0.09%; and an alloy melt is obtained;

[0046] After the alloy melt is subjected to horizontal continuous casting, it is subjected to planetary rolling, cold drawing and annealing treatment in sequence to obtain a high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube. The temperature of the horizontal continuous casting treatment is 1250°C, the billet drawing speed is 1.2m / min, the billet drawing frequency is 90 times / h, the graphite crystallizer is assisted by electromagnetic stirring treatment; the planetary rolling treatment refers to the use of a three-roller rolling mill or a four-roller rolling mill. The three-roller planetary rolling technology is mature and widely used, and is particularly suitable for the production of metal pipes such as copper pipes and steel pipes; and the four-roller planetary rolling is improved and innovated on this basis, improving the stability and efficiency of rolling to achieve a deformation of 90%; the applied deformation of the cold drawing treatment is 40%; the annealing treatment refers to annealing treatment at a temperature of 480°C for 1h.

[0047] The CuNi10Fe1Mn alloy copper tube obtained based on the above steps was subjected to performance tests. The test results are shown in Tables 1 and 2. The metallographic images of the cross section are shown in Figure 1 As shown, the metallographic image of the longitudinal section is as follows Figure 2 As shown:

[0048] Table 1:

[0049]

[0050] Table 2:

[0051]

[0052] A method for preparing a high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube comprises the following steps:

[0053] The following percentages are used for smelting: Ni content is 9.35%, Fe content is 1.30%, Mn content is 0.73%, the total amount of impurity elements does not exceed 0.2%, and the balance is Cu; among the impurity elements, C content is 0.005%, Co content is 0.002%, P content is 0.006%, Pb content is 0.008%, S content is 0.005%, Sn content is 0.007%, and Zn content is 0.11%; and an alloy melt is obtained;

[0054] After the alloy melt is subjected to horizontal continuous casting, planetary rolling, cold drawing and annealing treatment are carried out in sequence to obtain a high-strength and corrosion-resistant CuNi10Fe1Mn alloy copper tube. The temperature of the horizontal continuous casting treatment is 1300°C, the billet drawing speed is 0.8m / min, the billet drawing frequency is 120 times / h, the graphite crystallizer is assisted by electromagnetic stirring treatment; the planetary rolling treatment refers to the use of a three-roller rolling mill or a four-roller rolling mill. The three-roller planetary rolling technology is mature and widely used, and is particularly suitable for the production of metal pipes such as copper pipes and steel pipes; and the four-roller planetary rolling is improved and innovated on this basis, improving the stability and efficiency of rolling to achieve a deformation of 70%; the applied deformation of the cold drawing treatment is 50%; the annealing treatment refers to annealing treatment at a temperature of 500°C for 1h.

[0055] Example 3

[0056] A method for preparing a high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube comprises the following steps:

[0057] The following percentages are used for smelting: Ni content is 9.68%, Fe content is 1.42%, Mn content is 0.71%, the total amount of impurity elements does not exceed 0.2%, and the balance is Cu; among the impurity elements, C content is 0.004%, Co content is 0.005%, P content is 0.007%, Pb content is 0.007%, S content is 0.005%, Sn content is 0.006%, and Zn content is 0.12%; and an alloy melt is obtained;

[0058] After the alloy melt is subjected to horizontal continuous casting, planetary rolling, cold drawing and annealing treatment are carried out in sequence to obtain a high-strength and corrosion-resistant CuNi10Fe1Mn alloy copper tube. The temperature of the horizontal continuous casting treatment is 1200°C, the billet drawing speed is 3m / min, the billet drawing frequency is 80 times / h, the graphite crystallizer is assisted by electromagnetic stirring treatment; the planetary rolling treatment refers to the use of a three-roller rolling mill or a four-roller rolling mill. The three-roller planetary rolling technology is mature and widely used, and is particularly suitable for the production of metal pipes such as copper pipes and steel pipes; and the four-roller planetary rolling is improved and innovated on this basis, improving the stability and efficiency of rolling to achieve a deformation of 50%; the applied deformation of the cold drawing treatment is 20%; the annealing treatment refers to annealing treatment at a temperature of 400°C for 2h.

[0059] Example 4

[0060] A method for preparing a high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube comprises the following steps:

[0061] The following percentages are used for smelting: Ni content is 9.86%, Fe content is 1.50%, Mn content is 0.78%, the total amount of impurity elements does not exceed 0.2%, and the balance is Cu; among the impurity elements, C content is 0.005%, Co content is 0.004%, P content is 0.006%, Pb content is 0.006%, S content is 0.005%, Sn content is 0.008%, and Zn content is 0.15%; and an alloy melt is obtained;

[0062] After the alloy melt is subjected to horizontal continuous casting, planetary rolling, cold drawing and annealing treatment are carried out in sequence to obtain a high-strength and corrosion-resistant CuNi10Fe1Mn alloy copper tube. The temperature of the horizontal continuous casting treatment is 1250°C, the billet drawing speed is 2m / min, the billet drawing frequency is 100 times / h, the graphite crystallizer is assisted by electromagnetic stirring treatment; the planetary rolling treatment refers to the use of a three-roller rolling mill or a four-roller rolling mill. The three-roller planetary rolling technology is mature and widely used, and is particularly suitable for the production of metal pipes such as copper pipes and steel pipes; and the four-roller planetary rolling is improved and innovated on this basis, improving the stability and efficiency of rolling to achieve a deformation of 60%; the applied deformation of the cold drawing treatment is 35%; the annealing treatment refers to annealing treatment at a temperature of 450°C for 1.5h.

[0063] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube, characterized in that: In the CuNi10Fe1Mn alloy copper tube, the Ni content is 9.0%-11.0%, the Fe content is 1.0%-2.0%, the Mn content is 0.5%-1.0%, the total amount of impurity elements does not exceed 0.2%, and the balance is Cu.

2. The high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube according to claim 1, characterized in that: Among the impurity elements, C content is ≤0.05%, Co content is ≤0.1%, P content is ≤0.02%, Pb content is ≤0.02%, S content is ≤0.05%, Sn content is ≤0.03%, and Zn content is ≤0.5%.

3. The high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube according to claim 1, characterized in that: The average grain size of the CuNi10Fe1Mn alloy copper tube is ≤50 μm.

4. The high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube according to claim 1, characterized in that: The tensile strength of the CuNi10Fe1Mn alloy copper tube is ≥340MPa.

5. The high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube according to claim 1, characterized in that: The yield strength of the CuNi10Fe1Mn alloy copper tube is ≥120MPa.

6. The high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube according to claim 1, characterized in that: The elongation of the CuNi10Fe1Mn alloy copper tube is ≥35%.

7. The high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube according to claim 1, characterized in that: The hardness of the CuNi10Fe1Mn alloy copper tube is ≥75HRF.

8. A method for preparing a high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube, characterized in that: The following steps are involved: Smelting is performed according to the following content percentages: Ni content is 9.0%-11.0%, Fe content is 1.0%-2.0%, Mn content is 0.5%-1.0%, the total amount of impurity elements does not exceed 0.2%, and the balance is Cu; among the impurity elements, C content is ≤0.05%, Co content is ≤0.1%, P content is ≤0.02%, Pb content is ≤0.02%, S content is ≤0.05%, Sn content is ≤0.03%, and Zn content is ≤0.5%; obtaining an alloy melt; The alloy melt is subjected to horizontal continuous casting treatment, and then sequentially subjected to planetary rolling treatment, cold drawing treatment and annealing treatment to obtain a high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube.

9. The method for preparing the high-strength, corrosion-resistant CuNi10Fe1Mn alloy copper tube according to claim 8, characterized in that: The temperature of the horizontal continuous casting process is 1200°C-1300°C, assisted by electromagnetic stirring, and the electromagnetic stirring rate is 2000r / min-3000r / min; The planetary rolling process refers to a process of rolling through a three-roll mill or a four-roll mill to achieve a deformation of 30%-90%; the temperature of the planetary rolling process is 700-800°C, the speed of the planetary rolling process is 5-30m / min, and the atmosphere protection is a H2-N2 mixed atmosphere.

10. The method for preparing the high-strength and corrosion-resistant CuNi10Fe1Mn alloy copper tube according to claim 8, characterized in that: The applied deformation amount of the cold drawing process is 20%-50%, and the number of cold drawing processes is 1-4 times; The annealing treatment refers to an annealing treatment performed at a temperature of 400° C. to 500° C. for 1 h to 2 h, with nitrogen or argon gas being used as an atmosphere protection during the annealing treatment.

Images