Manufacturing method of copper-nickel alloy pipe with excellent high-temperature plasticity

Abstract

The invention provides a manufacturing method of a copper-nickel alloy pipe with excellent high-temperature plasticity. The manufacturing method comprises the following steps that S1, Ni, Fe, Mn, Ti, CuMg20 and Cu raw materials are weighed according to components of a nickel-based alloy pipe; s2, raw materials of Cu, Ni, Fe, Mn and Ti are smelted, CuMg20 is added for deoxidation, and an alloy round ingot is obtained through casting; s3, the alloy round ingot is subjected to homogenizing annealing; s4, forging and upsetting the alloy round ingot to obtain an upset round ingot; s5, performing hot extrusion on the upset round ingot to obtain a tubular billet; s6, the tubular billet is subjected to cold rolling, and annealing is conducted between pass cold rolling; and S7, the tubular billet is subjected to heat treatment, and the copper-nickel alloy pipe is obtained. According to the method, the uniformity and thermoplasticity of the alloy structure are improved, the plasticity and comprehensive mechanical performance of the copper-nickel alloy pipe in the high-temperature environment are remarkably improved, and the method is stable, high in repeatability and beneficial to large-scale production of the high-quality copper-nickel alloy pipe.

Description

Technical Field

[0001] This invention relates to the field of pipe processing technology, and in particular to a method for manufacturing copper-nickel alloy pipes with excellent high-temperature plasticity. Background Technology

[0002] Copper-nickel alloys are widely used in marine engineering, petrochemicals and other fields due to their good corrosion resistance, thermal conductivity and mechanical properties. However, traditional copper-nickel alloy tubes often exhibit a sharp decline in plasticity at high temperatures (above 400°C), which limits their processing and performance. In the current technology, conventional copper-nickel alloy tubes are mainly manufactured through processes such as casting, hot extrusion, cold rolling and annealing. However, under high temperature conditions, problems such as grain boundary weakening and precipitate aggregation lead to a significant reduction in their plasticity. Although some studies have improved their high-temperature performance by adding trace elements, this often sacrifices electrical conductivity or corrosion resistance, and the manufacturing process is complex and costly, making it difficult to achieve industrial production. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a manufacturing method for copper-nickel alloy tubes with excellent high-temperature plasticity. The manufacturing method includes the following main steps: batching, melting and casting, homogenization heat treatment, forging, hot extrusion, cold working and finished product treatment. By optimizing the parameters and processes of each step, the uniformity of the alloy structure and thermoplasticity are effectively improved, and the plasticity and comprehensive mechanical properties of the copper-nickel alloy tubes in high-temperature environments are significantly enhanced. This method is suitable for industrial fields with stringent requirements for high-temperature plasticity. The process is stable and highly repeatable, which is conducive to the large-scale production of high-quality copper-nickel alloy tubes.

[0004] The technical solution adopted in this invention is: A method for manufacturing a copper-nickel alloy tube with excellent high-temperature plasticity, comprising the following steps: Step S1. Batching: The copper-nickel alloy tube comprises the following components: Ni 9.5-32%, Fe 1-2.5%, Mn 0.5-1.5%, Ti 0.05-0.15%, CuMg2O 0.2-0.5%, with the balance being Cu. The total of the above is 100%. Weigh the raw materials Ni, Fe, Mn, Ti, CuMg2O, and Cu according to the composition of the copper-nickel alloy. Step S2. Melting and casting: Cu, Ni, Fe, Mn and Ti are added to the furnace in sequence for melting, then CuMg2O is added for deoxidation, and finally the alloy ingots are cast. Step S3. Homogenization heat treatment: The alloy ingot is subjected to homogenization annealing, followed by water quenching; Step S4. Forging: Heat the alloy round ingot that was water quenched in step S3, then forge and upset it, and finally machine the surface to obtain the upset round ingot. Step S5. Hot extrusion: The upset round ingot is heated and hot extruded to obtain a tube; Step S6. Cold working: The tube is subjected to multiple cold rolling passes, with annealing performed between each cold rolling pass; Step S7. Finished product processing: The cold-rolled tube from step S6 is heat-treated to obtain a high-temperature ductile copper-nickel alloy tube.

[0005] Preferably, in the manufacturing method of the copper-nickel alloy tube with excellent high-temperature plasticity, the melting temperature in step S2 is 1350-1450℃, and the outer diameter of the alloy ingot is φ120-φ180mm.

[0006] Preferably, in the manufacturing method of the copper-nickel alloy tube with excellent high-temperature plasticity, the homogenization annealing in step S3 specifically involves: holding the alloy ingot at 800-850℃ for 2 hours, and then raising the temperature to 830-880℃ and holding it for 2 hours.

[0007] Preferably, in the manufacturing method of the copper-nickel alloy tube with excellent high-temperature plasticity, the heating temperature in step S4 is 850-950℃, and the outer diameter of the upset round ingot is φ180-φ250mm.

[0008] Preferably, in the method for manufacturing the copper-nickel alloy tube with excellent high-temperature plasticity, the heating temperature in step S5 is 900-1000℃.

[0009] Preferably, in the manufacturing method of the copper-nickel alloy tube with excellent high-temperature plasticity, the hot extrusion in step S5 specifically involves placing the heated upsetting round ingot into a preheated mold for hot extrusion, controlling the temperature of the preheated mold to be 450-500℃ and the extrusion speed to be 50-80mm / s.

[0010] Preferably, in the manufacturing method of the copper-nickel alloy tube with excellent high-temperature plasticity, the deformation amount per pass in step S6 is 40-50%, the annealing temperature is 750-850℃, and the annealing time is 30-45min.

[0011] Preferably, in the manufacturing method of the copper-nickel alloy tube with excellent high-temperature plasticity, the heat treatment temperature in step S7 is 700-830℃ and the holding time is 10-25min.

[0012] Advantages of this invention: The present invention discloses a method for manufacturing copper-nickel alloy tubes with excellent high-temperature plasticity. The manufacturing method includes batching, casting, homogenization heat treatment, forging, hot extrusion, cold working, and finished product treatment. By optimizing the parameters and processes of each step, the uniformity of the alloy structure and thermoplasticity are effectively improved, and the plasticity and comprehensive mechanical properties of the copper-nickel alloy tubes under high-temperature conditions are significantly enhanced. This method is suitable for industrial fields with stringent requirements for high-temperature plasticity. The method is stable, highly repeatable, and conducive to the large-scale production of high-quality copper-nickel alloy tubes. Detailed Implementation

[0013] The present invention will be further described below with reference to specific embodiments.

[0014] Example 1 A method for manufacturing a copper-nickel alloy pipe with a Φ25*2 specification and BFe10-1-1 material exhibiting excellent high-temperature plasticity includes the following steps: Step S1. Batching: The copper-nickel alloy tube comprises the following components: Ni 10.2%, Fe 1.2%, Mn 0.8%, Ti 0.05%, CuMg2O 0.2%, with the balance being Cu. The total of the above is 100%. Weigh the raw materials Ni, Fe, Mn, Ti, CuMg2O, and Cu according to the composition of the copper-nickel alloy. Step S2. Melting and casting: Cu, Ni, Fe, Mn and Ti raw materials are added to an industrial frequency induction furnace for melting at a melting temperature of 1380℃. Then CuMg2O is added for deoxidation, and finally alloy round ingots with an outer diameter of φ140mm are cast. Step S3. Homogenization heat treatment: The alloy round ingot is held at 830℃ for 2 hours, then heated to 850℃ and held for 2 hours for homogenization annealing, followed by water quenching; Step S4. Forging: Heat the alloy round ingot quenched in step S3 to 880℃, then forge and upset it, and finally machine the surface to obtain an upset round ingot with an outer diameter of φ180mm. Step S5. Hot extrusion: Heat the upset round ingot to 950℃, put the heated upset round ingot into a preheated mold for hot extrusion, control the temperature of the preheated mold to 470℃, and the extrusion speed to 75mm / s to obtain a φ84*10mm tube. Step S6. Cold working: The φ84*10mm tube is subjected to multiple cold rolling passes, specifically φ84*10mm→48*5→48*5→41*3.5→25*2. Annealing is performed between the cold rolling passes at a temperature of 750℃ for 30 minutes. Step S7. Finished product processing: The cold-rolled tube from step S6 is subjected to heat treatment at a temperature of 720℃ for 10 minutes to obtain a high-temperature ductile copper-nickel alloy tube.

[0015] The copper-nickel alloy pipes manufactured in Example 1 were subjected to performance testing, and the test results are shown in Table 1.

[0016] Table 1

[0017] As can be seen from Table 1 above, the Φ25*2 specification tube made of BFe10-1-1 copper-nickel alloy prepared in Example 1 maintains ≥50% high-temperature plasticity in the range of 800℃ to 1000℃, demonstrating excellent performance.

[0018] Example 2 A method for manufacturing a copper-nickel alloy pipe with a Φ19*1.5 specification and BFe30-1-1 material exhibiting excellent high-temperature plasticity includes the following steps: Step S1. Batching: The copper-nickel alloy tube comprises the following components: Ni 30.5%, Fe 1.35%, Mn 1.2%, Ti 0.06%, CuMg2O 0.25%, with the balance being Cu. The total of the above is 100%. Weigh the raw materials Ni, Fe, Mn, Ti, CuMg2O, and Cu according to the composition of the copper-nickel alloy. Step S2. Melting and casting: Cu, Ni, Fe, Mn and Ti raw materials are added to an industrial frequency induction furnace for melting at a melting temperature of 1430℃. Then CuMg2O is added for deoxidation, and finally alloy round ingots with an outer diameter of φ180mm are cast. Step S3. Homogenization heat treatment: The alloy round ingot is held at 850℃ for 2 hours, then heated to 870℃ and held for 2 hours for homogenization annealing, followed by water quenching; Step S4. Forging: The alloy round ingot quenched in step S3 is heated to 950°C, then forged and upset, and finally the surface is machined to obtain an upset round ingot with an outer diameter of φ235mm. Step S5. Hot extrusion: Heat the upset round ingot to 980℃, put the heated upset round ingot into a preheated mold for hot extrusion, control the temperature of the preheated mold to 470℃, and the extrusion speed to 70mm / s to obtain a φ90*12mm tube. Step S6. Cold working: The φ90*12mm tube is subjected to multiple cold rolling passes, specifically φ90*12mm→φ60*6→φ48*4.5→φ41*3.5→φ25*2.5→φ19*1.5. Annealing is performed between the cold rolling passes at a temperature of 830℃ for 35 minutes. Step S7. Finished product processing: The cold-rolled tube from step S6 is subjected to heat treatment at a temperature of 830℃ for 10 minutes to obtain a high-temperature ductile copper-nickel alloy tube.

[0019] The copper-nickel alloy pipes manufactured in Example 2 were subjected to performance testing, and the test results are shown in Table 2.

[0020] Table 2

[0021] As can be seen from Table 2 above, the Φ19*1.5 specification tube prepared in Example 2, made of BFe30-1-1 copper-nickel alloy, maintains ≥38% high-temperature plasticity in the range of 800℃ to 1000℃, exhibiting excellent performance.

[0022] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for manufacturing a copper-nickel alloy tube with excellent high-temperature plasticity, characterized in that: Includes the following steps: Step S1. Batching: The copper-nickel alloy tube comprises the following components: Ni 9.5-32%, Fe 1-2.5%, Mn 0.5-1.5%, Ti 0.05-0.15%, CuMg2O 0.2-0.5%, with the balance being Cu. The total of the above is 100%. Weigh the raw materials Ni, Fe, Mn, Ti, CuMg2O, and Cu according to the composition of the copper-nickel alloy. Step S2. Melting and casting: Cu, Ni, Fe, Mn and Ti raw materials are added to the furnace in sequence for melting, then CuMg2O is added for deoxidation, and finally the alloy round ingots are cast. Step S3. Homogenization heat treatment: The alloy ingot is subjected to homogenization annealing, followed by water quenching; Step S4. Forging: Heat the alloy round ingot that was water quenched in step S3, then forge and upset it, and finally machine the surface to obtain the upset round ingot. Step S5. Hot extrusion: The upset round ingot is heated and hot extruded to obtain a tube; Step S6. Cold working: The tube is subjected to multiple cold rolling passes, with annealing performed between each cold rolling pass; Step S7. Finished product processing: The cold-rolled tube from step S6 is heat-treated to obtain a high-temperature ductile copper-nickel alloy tube.

2. The method for manufacturing a copper-nickel alloy tube with excellent high-temperature plasticity according to claim 1, characterized in that: In step S2, the melting temperature is 1350-1450℃, and the outer diameter of the alloy ingot is φ120-φ180mm.

3. The method for manufacturing a copper-nickel alloy tube with excellent high-temperature plasticity according to claim 1, characterized in that: The homogenization annealing in step S3 specifically involves: holding the alloy ingot at 800-850℃ for 2 hours, and then raising the temperature to 830-880℃ and holding it for 2 hours.

4. The method for manufacturing a copper-nickel alloy tube with excellent high-temperature plasticity according to claim 1, characterized in that: In step S4, the heating temperature is 850-950℃, and the outer diameter of the upset round ingot is φ180-φ250mm.

5. The method for manufacturing a copper-nickel alloy tube with excellent high-temperature plasticity according to claim 1, characterized in that: The heating temperature in step S5 is 900-1000℃.

6. The method for manufacturing a copper-nickel alloy tube with excellent high-temperature plasticity according to claim 1, characterized in that: In step S5, hot extrusion specifically involves placing the heated upsetting round ingot into a preheated mold for hot extrusion, controlling the temperature of the preheated mold to be 450-500℃ and the extrusion speed to be 50-80mm / s.

7. The method for manufacturing a copper-nickel alloy tube with excellent high-temperature plasticity according to claim 1, characterized in that: In step S6, the deformation amount per pass is 40-50%, the annealing temperature is 750-850℃, and the annealing time is 30-45min.

8. The method for manufacturing a copper-nickel alloy tube with excellent high-temperature plasticity according to claim 1, characterized in that: In step S7, the heat treatment temperature is 700-830℃ and the holding time is 10-25 minutes.

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