Characterization and detection process of magnetic control copper pipe

Abstract

The invention relates to the technical field of non-ferrous metal processing, and discloses a characterization and detection process of a magnetic control copper pipe, which comprises the following steps: step 1, material preparation and cleaning: material selection, cleaning and drying are carried out, and preparation is made for the next step of vacuum melting; step 2, vacuum melting and deoxidation: selecting melting equipment, preparing in a vacuum environment, and adjusting melting parameters; step 3, converter and deoxidation: transferring the smelted copper liquid into a heat preservation furnace, and adding phosphorus for deoxidation treatment; fourthly, casting and detecting are conducted, specifically, the deoxidized copper liquid is transferred into a crystallizer, condensate is introduced for cooling, a copper blank is formed, and the specific position of the copper blank is selected for oxygen content preliminary detection; fifthly, heat treatment and extrusion forming are conducted, specifically, the copper blank is subjected to heat treatment in an induction heating furnace, and after heat treatment, the copper blank is extruded into a pipe blank in an extruding machine; and 6, rolling and finished product detection are conducted, specifically, the pipe blank is subjected to multi-pass stretching, a finished copper pipe is obtained, and characterization observation and quality detection are conducted on the copper pipe.

Description

Technical Field

[0001] The invention relates to the technical field of nonferrous metal processing, in particular to a characterization and detection process of a magnetron copper tube. Background Art

[0002] In the copper tube manufacturing process, especially in the production of magnetron copper tubes, the problems of low copper content and high oxygen content have always troubled manufacturers. These problems not only affect the electrical and thermal conductivity of the copper tube, but also lead to unstable rolling performance, thereby increasing production costs and scrap rates.

[0003] Specifically, when the copper content is lower than the standard requirements, the electrical and thermal conductivity of the copper tube will drop significantly, which directly affects its use effect and life in equipment such as microwave ovens. At the same time, excessive oxygen content will cause oxide inclusions to form inside the copper tube, which are prone to cracks and fractures during the rolling process, resulting in unstable rolling performance. This instability not only increases the difficulty and cost of the production process, but also causes the dimensional accuracy and mechanical properties of the final copper tube to fail to meet the standards.

[0004] In order to solve these problems, manufacturers usually take a series of measures to improve the quality and performance of copper tubes. For example, by optimizing the smelting process to reduce the oxygen content, using advanced deoxidizers to remove oxides in copper, and by precisely controlling rolling parameters to improve the stability of rolling performance. However, these measures often require a lot of manpower, material and financial resources, and the results are not necessarily ideal.

[0005] Therefore, it is an urgent need for the industry to develop a new copper tube manufacturing process that can effectively solve the problems of low copper content and high oxygen content. This new process should be able to ensure the electrical conductivity and thermal conductivity of the copper tube while improving the stability of its rolling performance, thereby reducing production costs and scrap rates. Summary of the invention

[0006] 1. Technical issues to be resolved

[0007] In view of the deficiencies in the prior art, the present invention provides a characterization and detection process for a magnetron copper tube, which has the advantages of high copper content, low oxygen content and stable rolling performance, and solves the problems of low copper content, high oxygen content and unstable rolling performance.

[0008] (II) Technical solution

[0009] To achieve the above object, the present invention provides the following technical solution: a characterization and detection process of a magnetron copper tube, comprising the following steps:

[0010] Step 1: Material preparation and cleaning: material selection, cleaning and drying to prepare for the next step of vacuum melting;

[0011] Step 2: Vacuum melting and deoxidation: Select melting equipment, prepare vacuum environment, and adjust melting parameters;

[0012] Step 3: Converter and deoxidation: transfer the smelted copper liquid into a holding furnace and add phosphorus for deoxidation;

[0013] Step 4, casting and testing: the deoxidized copper liquid is transferred into a crystallizer, cooled by condensate to form a copper billet, and a specific position of the copper billet is selected for preliminary oxygen content testing;

[0014] Step 5: Heat treatment and extrusion molding: heat treatment is performed on the copper billet in an induction heating furnace. After the heat treatment, the copper billet is extruded into a tube billet in an extruder;

[0015] Step 6: Rolling and finished product inspection: The tube blank is stretched multiple times to obtain the finished copper tube, and the copper tube is characterized, observed and inspected for quality.

[0016] Preferably, the step 1 comprises: selecting a copper rod with a content of 99.98% to 100% as a raw material, then using pure water to ultrasonically clean the copper rod, the rinsing time lasts for 10 minutes, and blowing the copper rod dry with nitrogen after cleaning.

[0017] Preferably, the preparation of the vacuum environment in step 2 is: after the smelting furnace is evacuated, the copper rod is placed in the smelting furnace, and the vacuum is maintained at 2.5×10 -3 Pa to 3×10 -3 Pa, nitrogen with a purity of more than 99% is introduced for protection during the smelting process, and granular graphite is used to cover the surface of the copper liquid.

[0018] Preferably, the step three comprises: transferring the smelted copper liquid into a holding furnace for holding, and achieving a diffusion deoxidation effect by standing for 4-6 hours, while continuing to introduce nitrogen with a purity of more than 99% to form a copper liquid surface protection cover, and adding 0.5-1 parts by mass of phosphorus into the holding furnace for deoxidation treatment.

[0019] Preferably, the smelting parameters in step 2 are set as follows: the smelting temperature is controlled at 1150° C. to 1200° C., and the smelting time is controlled at 1 to 1.5 h.

[0020] Preferably, in the casting in step 4, a semi-continuous vibration casting method is adopted to cool the condensate in the crystallizer from bottom to top to achieve unidirectional solidification.

[0021] Preferably, the preliminary test in step 4 is: sampling from the bottom of the copper billet and the pouring gate to test the oxygen content.

[0022] Preferably, the step five comprises: setting the heating temperature of the induction heating furnace to 300°C-550°C, the heating time to 25-30min, and introducing nitrogen with a purity of more than 99% for surface protection during the heating process, and then water-sealing the heated copper billet in a water-seal extruder to form a tube billet, the extrusion pressure is controlled at 300-350MPa, the extrusion temperature is controlled between 900°C-950°C, the extrusion speed is controlled at 6-9m / min, and the wall thickness deviation is controlled within the range of ±0.0020mm.

[0023] Preferably, the step six is ​​rolling: rolling is performed through 8-10 stretching processes to form a copper tube, the rolled copper tube is subjected to peeling and straightening treatments, and finally the copper tube is cut, and copper chips on the surface of the copper tube and oil stains inside the copper tube are removed.

[0024] Preferably, the characterization observation in step six includes observing the surface morphology of the copper tube using a scanning electron microscope, analyzing the main components and internal structure of the copper tube using an X-ray diffractometer, and finally testing the thickness, resistivity and conductivity of the copper tube.

[0025] Compared with the prior art, the present invention provides a characterization and detection process for magnetron copper tubes, which has the following features:

[0026] Beneficial effects:

[0027] 1. The present invention adopts vacuum melting and deoxidation, selects melting equipment, prepares a vacuum environment, and adjusts melting parameters. The vacuum melting technology can not only reduce the degree of oxidation during the melting process, but also allow precise control of the melting temperature. This control method helps to improve the quality of copper materials, thereby improving the purity and stability of copper tubes.

[0028] 2. The present invention transfers the deoxidized copper liquid into a crystallizer through casting and testing, cools it through condensate to form a copper billet, selects a specific position of the copper billet for preliminary oxygen content testing, and uses low-temperature condensate in combination with a crystallizer for directional solidification, which helps to obtain a uniform and dense copper structure, thereby improving the overall quality of the copper billet. The oxygen content is tested immediately after the casting is completed, so that problems can be discovered in time and corresponding adjustments can be made to ensure that the quality of the copper tube meets the standards.

[0029] 3. The present invention performs multi-pass stretching on the tube blank through rolling and finished product inspection to obtain a finished copper tube, and performs characterization observation and quality inspection on the copper tube. The multi-pass stretching process can gradually refine the grain structure of the copper tube and improve its strength and toughness. The copper tube characterization observation and quality inspection link ensures that the dimensional accuracy, appearance quality and physical and chemical properties of each copper tube can meet the predetermined index range, thereby producing high-quality copper tube products. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a process step diagram of the present invention. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] See also Figure 1 , the characterization and detection process of the magnetron copper tube includes the following steps:

[0033] Step 1: Material preparation and cleaning: Material selection, cleaning and drying are carried out to prepare for the next step of vacuum melting. Through material selection and thorough cleaning process, impurities and oil stains on the surface of raw materials can be effectively removed, reducing the risk of contamination in the subsequent melting process. The added drying step ensures that the material is dry, avoids moisture from entering the melting stage, and can maintain the purity of the vacuum melting environment;

[0034] Step 2: Vacuum melting and deoxidation: Select melting equipment, prepare vacuum environment, adjust melting parameters, and use vacuum melting technology to not only reduce the degree of oxidation during the melting process, but also allow precise control of the melting temperature. This control method helps to improve the quality of copper materials, thereby improving the purity and stability of copper tubes;

[0035] Step 3, converter and deoxidation: The smelted copper liquid is transferred to a holding furnace and phosphorus is added for deoxidation. The converter operation allows the copper liquid to continue to be heated or kept warm in a relatively stable environment, and the addition of phosphorus as a deoxidizer can effectively remove oxygen and other harmful gases in the copper liquid. This step helps prevent the formation of pores inside the casting and can also improve the electrical conductivity of the material.

[0036] Step 4, casting and testing: the deoxidized copper liquid is transferred into the crystallizer, cooled by condensate to form a copper billet, and a specific position of the copper billet is selected for preliminary oxygen content testing. The directional solidification using low-temperature condensate combined with the crystallizer helps to obtain a uniform and dense copper structure, thereby improving the overall quality of the copper billet. The oxygen content is tested immediately after the casting is completed, so that problems can be discovered in time and corresponding adjustments can be made to ensure that the quality of the copper tube meets the standards;

[0037] Step 5: Heat treatment and extrusion: The copper billet is heat treated in an induction heating furnace. After heat treatment, the copper billet is extruded into a tube billet in an extruder. The heat treatment process can improve the microstructure of the copper billet, such as eliminating stress, refining grains, etc., thereby enhancing its mechanical properties. The extrusion forming step uses high temperature and high pressure to deform the copper billet into a tube billet of the desired shape. This process not only improves production efficiency, but also ensures the dimensional accuracy and surface finish of the copper tube.

[0038] Step 6, rolling and finished product inspection: The tube blank is stretched for multiple times to obtain the finished copper tube, and the copper tube is characterized, observed and inspected for quality. The multi-pass stretching process can gradually refine the grain structure of the copper tube and improve its strength and toughness. The copper tube characterization, observation and quality inspection process ensures that the dimensional accuracy, appearance quality and physical and chemical properties of each copper tube can meet the predetermined index range, thereby producing high-quality copper tube products to meet the standards of Cu ≥ 99.99%, O ≤ 0.0005%, P ≤ 0.0006%, S ≤ 0.0015%, and Fe ≤ 0.0010%.

[0039] Example 1

[0040] A copper rod with a content of 99.99% was selected as the raw material, and then the copper rod was ultrasonically cleaned with pure water for 10 minutes (to remove surface impurities). After cleaning, the copper rod was blown dry with nitrogen (to prevent impurities from entering and reduce oxidation) to prepare for the next step of vacuum melting.

[0041] Example 2

[0042] Preparation of vacuum environment: After the melting furnace is evacuated, the copper rod is placed in it and the vacuum is maintained at 2.5×10 -3 Pa, during the smelting process, nitrogen with a purity of 99.8% is introduced for protection to prevent oxidation, and granular graphite is used to cover the surface of the copper liquid.

[0043] Melting parameter settings: melting temperature is controlled at 1150℃, and melting time is controlled at 1h.

[0044] Example 3

[0045] The smelted copper liquid is transferred to a holding furnace for insulation. By standing for 4 hours, the diffusion deoxidation effect is achieved. At the same time, nitrogen with a purity of 99.8% is continued to be introduced to form a protective cover on the surface of the copper liquid (to control the oxygen content). 0.6 parts by mass of phosphorus (P) is added to the holding furnace for deoxidation treatment to ensure that the oxygen content in the copper billet is extremely low.

[0046] Example 4

[0047] The semi-continuous vibration casting method is adopted to cool the condensate in the crystallizer from bottom to top, so as to achieve unidirectional solidification, which is beneficial to exhaust and prevent oxygen from entering.

[0048] Samples are taken from the bottom of the copper billet and the pouring gate to test the oxygen content to ensure that it meets the standard requirements.

[0049] Example 5

[0050] The heating temperature of the induction heating furnace is set to 350°C, and the heating time is set to 30 minutes. During the heating process, nitrogen with a purity of 99.8% is introduced for surface protection. The heated copper billet is then water-sealed extruded into a tube billet in a water-seal extruder. The extrusion pressure is set to 350MPa, the extrusion temperature is set to 950°C, the extrusion speed is set to 6.5m / min, and the wall thickness deviation is controlled within the range of ±0.0020mm.

[0051] Example 6

[0052] The copper tube is rolled through 9 stretching processes to form a copper tube (to improve the dimensional accuracy and mechanical properties of the tube), and the rolled copper tube is peeled (to eliminate surface defects) and straightened. Finally, the copper tube is cut and the copper chips on the surface and the oil stains inside the copper tube are removed.

[0053] Characterization observations include using a scanning electron microscope (SEM) to observe the surface morphology of the copper tube and using an X-ray diffractometer (XRD) to analyze the main components and internal structure of the copper tube to ensure that it meets industrial application standards.

[0054] Comparative Example 1

[0055] A copper rod with a content of 99.5% was selected as the raw material, and then the copper rod was ultrasonically cleaned with pure water for 10 minutes (to remove surface impurities). After cleaning, the copper rod was blown dry with nitrogen (to prevent impurities from entering and reduce oxidation) to prepare for the next step of vacuum melting.

[0056] Comparative Example 2

[0057] Preparation of vacuum environment: After the melting furnace is evacuated, the copper rod is placed in it and the vacuum is maintained at 3.5×10 -3 Pa, during the smelting process, nitrogen with a purity of 99.0% is introduced for protection to prevent oxidation, and granular graphite is used to cover the surface of the copper liquid.

[0058] Melting parameter settings: melting temperature is controlled at 1200℃, and melting time is controlled at 1.5h.

[0059] Comparative Example 3

[0060] The smelted copper liquid is transferred to a holding furnace for insulation. By standing for 5 hours, the diffusion deoxidation effect is achieved. At the same time, nitrogen with a purity of more than 99.8% is continuously introduced to form a protective cover on the surface of the copper liquid (to control the oxygen content) to ensure that the oxygen content in the copper billet is extremely low.

[0061] Comparative Example 4

[0062] The semi-continuous vibration casting method is adopted to cool the crystallizer with water from bottom to top to achieve unidirectional water solidification, which is conducive to exhaust and prevent oxygen ingress.

[0063] Take samples from the bottom of the copper billet to test the oxygen content to ensure that it meets the standard requirements.

[0064] Comparative Example 5

[0065] The heating temperature of the induction heating furnace is set to 450°C, and the heating time is set to 25 minutes. At the same time, nitrogen with a purity of more than 99.8% is introduced during the heating process for surface protection. The heated copper billet is then water-sealed extruded into a tube billet in a water-seal extruder. The extrusion pressure is controlled at 250MPa, the extrusion temperature is controlled between 950°C, the extrusion speed is controlled at 8m / min, and the wall thickness deviation is controlled within the range of ±0.0020mm.

[0066] Comparative Example 6

[0067] The copper tube is rolled through 7 stretching processes to improve the dimensional accuracy and mechanical properties of the tube. The rolled copper tube is peeled (to eliminate surface defects) and straightened. Finally, the copper tube is cut and the copper chips on the surface and the oil stains inside the copper tube are removed.

[0068] The embodiment and the comparative example are made into copper tubes by supplementing other steps of the present invention, and the thickness, resistivity and conductivity of the copper tubes are tested. The test results are shown in the following table:

[0069]

[0070] From the data in the table, Examples 1-6 are superior to Comparative Examples 1-6 in thickness control, resistivity and conductivity.

[0071] Comparison of Example 1 with Comparative Example 1:

[0072] Difference in raw material purity: Example 1 uses a 99.99% copper rod, and Comparative Example 1 uses a 99.5% copper rod. The high-purity copper raw material in Example 1 means that the impurity content is low, and the conductivity and mechanical properties will be improved.

[0073] Comparison of Example 2 with Comparative Example 2

[0074] Difference between vacuum degree and nitrogen purity:

[0075] Example 2: Maintain vacuum at 2.5×10^ -3 Pa, using 99.8% nitrogen.

[0076] Comparative Example 2: Maintain vacuum at 3.5×10^ -3 Pa, using 99.0% nitrogen.

[0077] Differences in smelting parameters: Example 2: smelting temperature 1150°C, time 1 hour. Comparative Example 2: smelting temperature 1200°C, time 1.5 hours. Comparative Example 2: Lower vacuum and lower nitrogen purity can lead to more oxidation and other impurities being introduced.

[0078] The higher melting temperature and longer melting time of Comparative Example 2 can lead to more energy consumption and possible microstructure changes.

[0079] Comparison of Example 3 with Comparative Example 3

[0080] Differences in holding time and addition of deoxidizer: Example 3 was left standing for 4 hours, and 0.6 parts by mass of phosphorus was added for deoxidation. Comparative Example 3 was left standing for 5 hours, and the addition of deoxidizer was not explicitly mentioned. Although the longer holding time of Comparative Example 3 contributed to a better deoxidation effect, the lack of addition of deoxidizer resulted in a higher final oxygen content than Example 3.

[0081] Comparison of Example 4 with Comparative Example 4

[0082] Differences in casting methods and detection points: Example 4 uses semi-continuous vibration casting, and samples are taken from the bottom and the gate to detect the oxygen content. Comparative Example 4 also uses semi-continuous vibration casting, but samples are taken from the bottom to detect the oxygen content. Multi-point sampling in Example 4 can provide more comprehensive quality control.

[0083] Comparison of Example 5 with Comparative Example 5

[0084] Differences in heating and extrusion parameters: Example 5: heating temperature 350°C, time 30 minutes, extrusion pressure 350 MPa, speed 6.5 m / min. Comparative Example 5: heating temperature 450°C, time 25 minutes, extrusion pressure 250 MPa, speed 8 m / min. The higher heating temperature and faster extrusion speed of Comparative Example 5 will lead to rapid changes in the microstructure of the material, affecting the final performance.

[0085] Comparison of Example 6 with Comparative Example 6

[0086] Difference in the number of stretching treatments: Example 6 was stretched through 9 passes. Comparative Example 6 was stretched through 7 passes. The number of stretching times in Comparative Example 6 was small, which would reduce dimensional accuracy and mechanical properties.

[0087] Summary: The embodiment uses higher purity raw materials, complete process control and additional post-processing steps to improve the thickness control, resistivity and conductivity of the copper tube, thereby ensuring that the copper tube meets industrial application standards and has high stability and low oxygen content.

[0088] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Characterization and detection process of magnetron copper tube, characterized in that: The following steps are involved: Step 1: Material preparation and cleaning: material selection, cleaning and drying to prepare for the next step of vacuum melting; Step 2: Vacuum melting and deoxidation: Select melting equipment, prepare vacuum environment, and adjust melting parameters; Step 3: Converter and deoxidation: transfer the smelted copper liquid into a holding furnace and add phosphorus for deoxidation; Step 4, casting and testing: the deoxidized copper liquid is transferred into a crystallizer, cooled by condensate to form a copper billet, and a specific position of the copper billet is selected for preliminary oxygen content testing; Step 5: Heat treatment and extrusion molding: heat treatment is performed on the copper billet in an induction heating furnace. After the heat treatment, the copper billet is extruded into a tube billet in an extruder; Step 6: Rolling and finished product inspection: The tube blank is stretched multiple times to obtain the finished copper tube, and the copper tube is characterized, observed and inspected for quality.

2. The characterization and detection process of the magnetron copper tube according to claim 1, characterized in that: The step 1 comprises: selecting a copper rod with a content of 99.98% to 100% as a raw material, then using pure water to ultrasonically clean the copper rod for 10 minutes, and blowing the copper rod dry with nitrogen after cleaning.

3. The characterization and detection process of the magnetron copper tube according to claim 1 is characterized in that: Preparation of vacuum environment in step 2: After the melting furnace is evacuated, the copper rod is placed in the furnace and the vacuum is maintained at 2.5×10 -3 Pa to 3×10 -3 Pa, nitrogen with a purity of more than 99% is introduced for protection during the smelting process, and granular graphite is used to cover the surface of the copper liquid.

4. The characterization and detection process of the magnetron copper tube according to claim 1 is characterized in that: The smelting parameters in step 2 are set as follows: the smelting temperature is controlled at 1150° C. to 1200° C., and the smelting time is controlled at 1 to 1.5 h.

5. The characterization and detection process of the magnetron copper tube according to claim 1, characterized in that: The step three comprises: transferring the smelted copper liquid into a holding furnace for holding, and achieving a diffusion deoxidation effect by standing for 4-6 hours, while continuing to introduce nitrogen with a purity of more than 99% to form a copper liquid surface protection cover, and adding 0.5-1 parts by mass of phosphorus in the holding furnace for deoxidation treatment.

6. The characterization and detection process of the magnetron copper tube according to claim 1, characterized in that: Casting in step 4: using a semi-continuous vibration casting method, the condensate in the crystallizer is cooled from bottom to top to achieve unidirectional solidification.

7. The characterization and detection process of the magnetron copper tube according to claim 1 is characterized in that: The preliminary test in step 4 is: sampling from the bottom of the copper billet and the pouring gate to test the oxygen content.

8. The characterization and detection process of the magnetron copper tube according to claim 1, characterized in that: The step five comprises: setting the heating temperature of the induction heating furnace to 300°C-550°C, the heating time to 25-30min, introducing nitrogen with a purity of more than 99% for surface protection during the heating process, and then water-sealing extruding the heated copper billet into a tube billet in a water-sealed extruder, controlling the extrusion pressure to 300-350MPa, the extrusion temperature to 900°C-950°C, the extrusion speed to 6-9m / min, and controlling the wall thickness deviation to be within the range of ±0.0020mm.

9. The characterization and detection process of the magnetron copper tube according to claim 1, characterized in that: The step six is ​​rolling: rolling is performed through 8-10 stretching processes to form a copper tube, the rolled copper tube is subjected to peeling and straightening processes, and finally the copper tube is cut, and copper chips on the surface of the copper tube and oil stains inside the copper tube are removed.

10. The characterization and detection process of the magnetron copper tube according to claim 1, characterized in that: The characterization observation in step six includes observing the surface morphology of the copper tube using a scanning electron microscope, analyzing the main components and internal structure of the copper tube using an X-ray diffractometer, and finally testing the thickness, resistivity and conductivity of the copper tube.

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