High-surface tension red copper and preparation method thereof

Abstract

The invention provides high-surface-tension red copper and a preparation method thereof, and belongs to the technical field of copper alloy manufacturing. According to the method, in the red copper preparation process, through multiple times of rolling and heat treatment, the red copper can have very good mechanical properties, and the surface tension of the red copper can be effectively improved by pickling the annealed red copper after bell jar type annealing is finished and strictly controlling the components in the acid liquor and the pickling speed during pickling. The result of the embodiment shows that the tensile strength of the prepared red copper is larger than or equal to 220 MPa, the elongation A11.3 is larger than or equal to 5%, the hardness is larger than or equal to 50 HV, and the surface tension coefficient is larger than or equal to 40 dyn / cm.

Description

Technical Field

[0001] The invention relates to the technical field of copper alloy manufacturing, in particular to high surface tension red copper and a preparation method thereof. Background Art

[0002] Copper is industrial pure copper. Because it has a rose red color and turns purple after an oxide film is formed on the surface, it is generally called copper, also known as red copper. Copper processing materials can be divided into four categories according to their composition: ordinary copper (T1, T2, T3), oxygen-free copper (TU1, TU2 and high-purity, vacuum oxygen-free copper), deoxidized copper (TUP, TUMn) and special copper with a small amount of alloy elements added (arsenic copper, tellurium copper, silver copper). Copper has good electrical and thermal conductivity due to its low impurity content, but because copper is a precious metal and has a high cost of use, other metals are sometimes composited with copper in industry to reduce costs, and the surface tension of the copper substrate is a key technical indicator for composite processing. The lower the surface tension of copper, the more difficult it is to process during the composite processing process, and the higher the production cost. Therefore, how to improve the surface tension of copper has become a technical problem that needs to be solved in this field. Summary of the invention

[0003] The object of the present invention is to provide a high surface tension copper and a preparation method thereof. The copper prepared by the present invention not only has excellent mechanical properties, but also has a surface tension coefficient of ≥40dyn / cm.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0005] The present invention provides a method for preparing high surface tension copper, comprising the following steps:

[0006] (1) semi-continuously casting and hot rolling copper in sequence to obtain hot-rolled copper;

[0007] (2) subjecting the hot-rolled copper obtained in step (1) to initial rolling, finished product rolling and bell-type annealing in sequence to obtain annealed copper;

[0008] (3) pickling the annealed copper obtained in step (2) to obtain high surface tension copper;

[0009] The pickling speed is 10-20 m / min; the concentration of the acid solution during pickling is 10-25 wt.%, and the concentration of the passivation solution during pickling is 0.025-0.07 wt.%.

[0010] Preferably, the temperature of the semi-continuous casting in step (1) is 1150-1200° C., and the pulling rate of the semi-continuous casting is 60-140 mm / min.

[0011] Preferably, in step (1), the hot rolling temperature is 800-950° C., the total deformation of the hot rolling is 80-95%, and the number of hot rolling passes is 7-11.

[0012] Preferably, the total deformation of the initial rolling in step (2) is 40-95%, and the initial rolling is cold rolling.

[0013] Preferably, the total deformation of the finished product during rolling in step (2) is 40-80%, and the finished product is rolled by cold rolling.

[0014] Preferably, the temperature of the bell-jar annealing in step (2) is 400-530° C., and the holding time of the bell-jar annealing is 7-13 h.

[0015] Preferably, the acid in the acid solution in step (3) is sulfuric acid.

[0016] Preferably, the pickling speed in step (3) is 12 to 18 m / min; the concentration of the acid solution during pickling is 12 to 22 wt.%, and the concentration of the passivation solution during pickling is 0.03 to 0.065 wt.%.

[0017] The invention provides red copper with high surface tension prepared by the preparation method described in the technical scheme.

[0018] Preferably, the chemical composition of the high surface tension copper includes, by mass percentage: Cu+Ag≥99.90%, Bi≤0.001%, Sb≤0.002%, As≤0.002%, Fe≤0.005%, Pb≤0.005% and S≤0.005%.

[0019] The present invention provides a method for preparing copper with high surface tension, comprising the following steps: (1) semi-continuously casting and hot rolling copper in sequence to obtain hot-rolled copper; (2) performing initial rolling, finished product rolling and bell-type annealing on the hot-rolled copper obtained in step (1) in sequence to obtain annealed copper; (3) pickling the annealed copper obtained in step (2) to obtain copper with high surface tension; the pickling speed is 10 to 20 m / min; the concentration of the acid solution during pickling is 10 to 25 wt.%, and the concentration of the passivation solution during pickling is 0.025 to 0.07 wt.%. In the process of preparing copper, the present invention uses multiple rolling and heat treatment to make the copper have good mechanical properties. After the bell-type annealing is completed, the annealed copper is pickled and the components in the acid solution during pickling and the pickling speed are strictly controlled, so that the surface tension of the copper can be effectively improved. The results of the embodiment show that the tensile strength of the copper prepared by the preparation method provided by the present invention is ≥220 MPa, and the elongation A is ≥220 MPa. 11.3 ≥5%, hardness ≥50HV, surface tension coefficient ≥40dyn / cm. DETAILED DESCRIPTION

[0020] The present invention provides a method for preparing high surface tension copper, comprising the following steps:

[0021] (1) semi-continuously casting and hot rolling copper in sequence to obtain hot-rolled copper;

[0022] (2) subjecting the hot-rolled copper obtained in step (1) to initial rolling, finished product rolling and bell-type annealing in sequence to obtain annealed copper;

[0023] (3) pickling the annealed copper obtained in step (2) to obtain high surface tension copper;

[0024] The pickling speed is 10-20 m / min; the concentration of the acid solution during pickling is 10-25 wt.%, and the concentration of the passivation solution during pickling is 0.025-0.07 wt.%.

[0025] The invention sequentially performs semi-continuous casting and hot rolling on red copper to obtain hot-rolled red copper.

[0026] The present invention has no particular limitation on the source of the copper, and copper prepared by a preparation method well known to those skilled in the art or commercially available copper may be used.

[0027] In the present invention, the temperature of the semi-continuous casting is preferably 1150-1200°C; the pulling rate of the semi-continuous casting is preferably 60-140 mm / min. As an embodiment of the present invention, the temperature of the semi-continuous casting may be 1150°C, 1160°C, 1170°C, 1180°C, 1190°C or 1200°C; the pulling rate of the semi-continuous casting may be 60 mm / min, 70 mm / min, 80 mm / min, 90 mm / min, 100 mm / min, 110 mm / min, 120 mm / min, 130 mm / min or 140 mm / min.

[0028] The present invention preferably heats the ingot obtained by semi-continuous casting before hot rolling; the heating temperature is preferably 800-950°C; and the heating time is preferably 4-10 hours. The present invention can keep the temperature of the ingot within the required range for hot rolling by heating, thereby facilitating subsequent hot rolling. As an embodiment of the present invention, the heating temperature can be 800°C, 820°C, 850°C, 880°C, 900°C, 920°C or 950°C; the heating time can be 4h, 5h, 6h, 7h, 8h, 9h or 10h.

[0029] In the present invention, the temperature of the hot rolling is preferably 800-950°C; the total deformation of the hot rolling is preferably 80-95%; and the number of hot rolling passes is preferably 7-11 passes. The present invention can improve the processing performance of the alloy through hot rolling, crush the coarse grains in the casting state, significantly heal the cracks, reduce or eliminate casting defects, transform the cast structure into a deformed structure, and improve the processing performance of red copper. As an embodiment of the present invention, the temperature of the hot rolling can be 800°C, 820°C, 850°C, 880°C, 900°C, 920°C or 950°C; the total deformation of the hot rolling can be 80%, 82%, 85%, 88%, 90%, 92% or 95%; the number of hot rolling passes can be 7 passes, 8 passes, 9 passes, 10 passes or 11 passes.

[0030] The present invention preferably performs milling on the hot-rolled product after hot rolling to obtain hot-rolled copper. The present invention has no particular limitation on the specific operation of the milling and the thickness of the milling, as long as the oxide layer on the surface of the product can be removed. As an embodiment of the present invention, the thickness of the milling can be 0.8 mm, 0.9 mm, 1 mm, 1.1 mm or 1.2 mm.

[0031] After obtaining the hot-rolled copper, the present invention sequentially performs initial rolling, finished product rolling and bell-type annealing on the hot-rolled copper to obtain annealed copper.

[0032] In the present invention, the total deformation of the initial rolling is preferably 40-95%; the initial rolling is preferably cold rolling. The present invention has no special restrictions on the deformation of a single pass and the number of passes during the cold rolling, which can be determined according to the technical common sense of those skilled in the art. The present invention can greatly reduce the thickness of the copper blank through initial rolling, which can eliminate casting defects, break coarse grains, and improve its performance on the one hand, and is conducive to the subsequent preparation of copper with a thickness that meets the requirements on the other hand. As an embodiment of the present invention, the total deformation of the initial rolling can be 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90% or 95%; the deformation of a single pass of the initial rolling can be 9-35%, or 9%, 10%, 15%, 20%, 25%, 30% or 35%; the number of passes of the initial rolling can be 4-14, or 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 or 14.

[0033] In the present invention, the thickness of the product obtained by the initial rolling is preferably 2 to 9.2 mm. The present invention controls the thickness of the product within the above range, so as to facilitate the subsequent preparation of red copper with a thickness that meets the requirements. As an embodiment of the present invention, the thickness of the product obtained by the initial rolling can be 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm or 9.2 mm.

[0034] The present invention preferably performs brushing on the product obtained by primary rolling. The present invention has no special limitation on the specific operation of the brushing, and it only needs to remove impurities on the surface of the product.

[0035] In the present invention, the total deformation of the finished product rolling is preferably 40-80%; the finished product rolling is preferably cold rolling. The present invention has no special limitation on the single-pass deformation and the number of passes during the rolling of the finished product, which can be determined according to the technical common sense of those skilled in the art. The present invention can further reduce the thickness of the copper blank through the rolling of the finished product, thereby obtaining copper with a thickness that meets the requirements. As an embodiment of the present invention, the total deformation of the finished product rolling can be 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75% or 80%; the single-pass deformation of the finished product rolling can be 9-36%, and can also be 9%, 10%, 15%, 20%, 25%, 30% or 36%; the number of passes of the finished product rolling can be 4-10 passes, and can also be 4 passes, 5 passes, 6 passes, 7 passes, 8 passes, 9 passes or 10 passes.

[0036] In the present invention, the thickness of the product obtained by rolling the finished product is preferably 0.5 to 4.95 mm. The present invention controls the thickness of the product within the above range, and the thickness meets the technical requirements. As an embodiment of the present invention, the thickness of the product obtained by rolling the finished product can be 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm or 4.95 mm.

[0037] The present invention preferably further comprises unwinding the product obtained by rolling the finished product. The present invention has no special limitation on the specific operation of unwinding, and the unwinding operation well known to those skilled in the art can be adopted.

[0038] In the present invention, the temperature of the bell-jar annealing is preferably 400-530°C; the holding time of the bell-jar annealing is preferably 7-13h. The present invention has no special limitation on the atmosphere of the bell-jar annealing. It can be determined according to the technical common sense of those skilled in the art as long as oxidation can be avoided during the bell-jar annealing process. The present invention can remove the residual internal stress in the metal through bell-jar annealing on the one hand, and on the other hand, it can play a role in homogenization treatment, making the internal structure of the metal more uniform. As an embodiment of the present invention, the temperature of the bell-jar annealing can be 400°C, 420°C, 450°C, 480°C, 500°C or 530°C; the holding time of the bell-jar annealing can be 7h, 8h, 9h, 10h, 11h, 12h or 13h.

[0039] After obtaining the annealed copper, the present invention performs pickling on the annealed copper to obtain high surface tension copper.

[0040] In the present invention, the pickling method is preferably immersion pickling; the pickling is preferably first washed with acid solution and then washed with passivation solution. In the present invention, the pickling speed is 10-20m / min, preferably 12-18m / min, more preferably 13-17m / min, and further preferably 15m / min; the concentration of the acid solution during pickling is 10-25wt.%, preferably 12-22wt.%, more preferably 15-20wt.%, and further preferably 18wt.%; the acid in the acid solution is preferably sulfuric acid; the concentration of the passivation solution during pickling is 0.025-0.07wt.%, preferably 0.03-0.065wt.%, more preferably 0.035-0.06wt.%, and further preferably 0.04-0.055wt.%. The present invention has no special limitation on the specific source of the passivating agent in the passivating solution, and a commercially available passivating agent well known to those skilled in the art can be used. In an embodiment of the present invention, the passivator in the passivation solution can be HC-09 passivator produced by Hangzhou Baimu Surface Technology Co., Ltd., and the main component is benzotriazole. The present invention uses acid washing to remove the oxide layer on the surface of copper, and then uses the passivation solution to passivate the surface of the copper alloy, thereby preventing it from being oxidized again. At the same time, by controlling the process parameters during acid washing, the surface tension of copper can be significantly improved.

[0041] The invention can make the copper have good mechanical properties through multiple rolling and heat treatment in the process of preparing copper, and can effectively improve the surface tension of the copper by pickling the annealed copper after the bell-type annealing and strictly controlling the components in the acid solution and the pickling speed during the pickling.

[0042] The present invention also provides high surface tension red copper prepared by the preparation method described in the above technical solution.

[0043] In the present invention, the chemical composition of the high surface tension copper preferably includes, by mass percentage: Cu+Ag≥99.90%, Bi≤0.001%, Sb≤0.002%, As≤0.002%, Fe≤0.005%, Pb≤0.005% and S≤0.005%.

[0044] The high surface tension red copper provided by the present invention not only has high tensile strength and hardness, but also has good toughness, and the surface tension is greatly improved.

[0045] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. 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.

[0046] Example 1

[0047] A method for preparing high surface tension copper comprises the following steps:

[0048] (1) performing semi-continuous casting on copper to obtain a cast billet, then heating the cast billet at 850° C. for 5 hours and then hot rolling it, and finally performing face milling to obtain hot-rolled copper; the temperature of the semi-continuous casting is 1187° C., the pulling rate of the semi-continuous casting is 120 mm / min; the temperature of the hot rolling is 850° C., the total deformation of the hot rolling is 85%, and the number of hot rolling passes is 7;

[0049] (2) the hot-rolled copper obtained in step (1) is subjected to preliminary rolling, brushing, finished product rolling, unwinding and bell-type annealing in sequence to obtain annealed copper; the total deformation of the preliminary rolling is 50%, the number of preliminary rolling passes is 4, and the preliminary rolling is cold rolling; the total deformation of the finished product rolling is 50%, the number of finished product rolling passes is 4, and the finished product rolling is cold rolling; the temperature of the bell-type annealing is 410° C., and the holding time of the bell-type annealing is 8 hours;

[0050] (3) pickling the annealed copper obtained in step (2) to obtain high surface tension copper; the pickling method is immersion pickling, the pickling speed is 12 m / min, the concentration of the acid solution during pickling is 12 wt.%, the acid in the acid solution is sulfuric acid, the concentration of the passivation solution during pickling is 0.031 wt.%, and the passivator in the passivation solution is HC-09 passivator produced by Hangzhou Baimu Surface Technology Co., Ltd.

[0051] The high surface tension red copper prepared in Example 1 has the following chemical compositions by mass percentage: Cu+Ag: 99.982%, Bi: 0.0001%, Sb: 0.001%, As: 0.0011%, Fe: 0.0011%, Pb: 0.0011% and S: 0.0017%.

[0052] Example 2

[0053] A method for preparing high surface tension copper comprises the following steps:

[0054] (1) performing semi-continuous casting on copper to obtain a cast billet, then heating the cast billet at 890° C. for 4 hours and then hot rolling it, and finally performing face milling to obtain hot-rolled copper; the temperature of the semi-continuous casting is 1155° C., the pulling rate of the semi-continuous casting is 140 mm / min; the temperature of the hot rolling is 890° C., the total deformation of the hot rolling is 90%, and the number of hot rolling passes is 9;

[0055] (2) the hot-rolled copper obtained in step (1) is subjected to preliminary rolling, brushing, finished product rolling, unwinding and bell-type annealing in sequence to obtain annealed copper; the total deformation of the preliminary rolling is 60%, the number of preliminary rolling passes is 5, and the preliminary rolling is cold rolling; the total deformation of the finished product rolling is 50%, the number of finished product rolling passes is 4, and the finished product rolling is cold rolling; the temperature of the bell-type annealing is 450° C., and the holding time of the bell-type annealing is 7 hours;

[0056] (3) pickling the annealed copper obtained in step (2) to obtain high surface tension copper; the pickling method is immersion pickling, the pickling speed is 15 m / min, the concentration of the acid solution during pickling is 15 wt.%, the acid in the acid solution is sulfuric acid, the concentration of the passivation solution during pickling is 0.04 wt.%, and the passivator in the passivation solution is HC-09 passivator produced by Hangzhou Baimu Surface Technology Co., Ltd.

[0057] The high surface tension red copper prepared in Example 2 has the following chemical compositions by mass percentage: Cu+Ag: 99.985%, Bi: 0.00009%, Sb: 0.001%, As: 0.0015%, Fe: 0.0012%, Pb: 0.001% and S: 0.0015%.

[0058] Example 3

[0059] A method for preparing high surface tension copper comprises the following steps:

[0060] (1) performing semi-continuous casting on copper to obtain a cast billet, then heating the cast billet at 920° C. for 4 hours and then hot rolling it, and finally performing face milling to obtain hot-rolled copper; the temperature of the semi-continuous casting is 1172° C., the pulling rate of the semi-continuous casting is 130 mm / min; the temperature of the hot rolling is 920° C., the total deformation of the hot rolling is 95%, and the number of hot rolling passes is 11;

[0061] (2) the hot-rolled copper obtained in step (1) is subjected to preliminary rolling, brushing, finished product rolling, unwinding and bell-type annealing in sequence to obtain annealed copper; the total deformation of the preliminary rolling is 70%, the number of preliminary rolling passes is 6, and the preliminary rolling is cold rolling; the total deformation of the finished product rolling is 60%, the number of finished product rolling passes is 6, and the finished product rolling is cold rolling; the temperature of the bell-type annealing is 460° C., and the holding time of the bell-type annealing is 8 hours;

[0062] (3) pickling the annealed copper obtained in step (2) to obtain high surface tension copper; the pickling method is immersion pickling, the pickling speed is 16 m / min, the concentration of the acid solution during pickling is 20 wt.%, the acid in the acid solution is sulfuric acid, the concentration of the passivation solution during pickling is 0.05 wt.%, and the passivator in the passivation solution is HC-09 passivator produced by Hangzhou Baimu Surface Technology Co., Ltd.

[0063] The high surface tension red copper prepared in Example 3 has the following chemical compositions by mass percentage: Cu+Ag: 99.982%, Bi: 0.00011%, Sb: 0.0011%, As: 0.0007%, Fe: 0.0015%, Pb: 0.0009% and S: 0.0014%.

[0064] Example 4

[0065] A method for preparing high surface tension copper comprises the following steps:

[0066] (1) performing semi-continuous casting on copper to obtain a cast billet, then heating the cast billet at 820° C. for 4 hours and then hot rolling it, and finally performing face milling to obtain hot-rolled copper; the temperature of the semi-continuous casting is 1198° C., the pulling rate of the semi-continuous casting is 70 mm / min; the temperature of the hot rolling is 820° C., the total deformation of the hot rolling is 80%, and the number of hot rolling passes is 7;

[0067] (2) the hot-rolled copper obtained in step (1) is subjected to preliminary rolling, brushing, finished product rolling, unwinding and bell-type annealing in sequence to obtain annealed copper; the total deformation of the preliminary rolling is 85%, the number of preliminary rolling passes is 8, and the preliminary rolling is cold rolling; the total deformation of the finished product rolling is 60%, the number of finished product rolling passes is 4, and the finished product rolling is cold rolling; the temperature of the bell-type annealing is 400° C., and the holding time of the bell-type annealing is 12 h;

[0068] (3) pickling the annealed copper obtained in step (2) to obtain high surface tension copper; the pickling method is immersion pickling, the pickling speed is 20 m / min, the concentration of the acid solution during pickling is 23 wt.%, the acid in the acid solution is sulfuric acid, the concentration of the passivation solution during pickling is 0.065 wt.%, and the passivator in the passivation solution is HC-09 passivator produced by Hangzhou Baimu Surface Technology Co., Ltd.

[0069] The high surface tension red copper prepared in Example 4 has the following chemical compositions by mass percentage: Cu+Ag: 99.979%, Bi: 0.0005%, Sb: 0.0015%, As: 0.0011%, Fe: 0.0018%, Pb: 0.001% and S: 0.0014%.

[0070] Comparative Example 1

[0071] A method for preparing red copper comprises the following steps:

[0072] (1) performing semi-continuous casting on copper to obtain a cast billet, then heating the cast billet at 850° C. for 6 hours and then hot rolling it, and finally performing face milling to obtain hot-rolled copper; the temperature of the semi-continuous casting is 1188° C., the pulling rate of the semi-continuous casting is 80 mm / min; the temperature of the hot rolling is 850° C., the total deformation of the hot rolling is 90%, and the number of hot rolling passes is 9;

[0073] (2) the hot-rolled copper obtained in step (1) is subjected to preliminary rolling, brushing, finished product rolling, unwinding and bell-type annealing in sequence to obtain annealed copper; the total deformation of the preliminary rolling is 90%, the number of preliminary rolling passes is 8, and the preliminary rolling is cold rolling; the total deformation of the finished product rolling is 50%, the number of finished product rolling passes is 4, and the finished product rolling is cold rolling; the temperature of the bell-type annealing is 470° C., and the holding time of the bell-type annealing is 8 hours;

[0074] (3) pickling the annealed copper obtained in step (2) to obtain copper; the pickling method is immersion pickling, the pickling speed is 9 m / min, the concentration of the acid solution during pickling is 8 wt.%, the acid in the acid solution is sulfuric acid, the concentration of the passivation solution during pickling is 0.075 wt.%, and the passivator in the passivation solution is HC-09 passivator produced by Hangzhou Baimu Surface Technology Co., Ltd.

[0075] The red copper prepared in Comparative Example 1 has the following chemical compositions by mass percentage: Cu+Ag: 99.987%, Bi: 0.0005%, Sb: 0.0005%, As: 0.0011%, Fe: 0.0011%, Pb: 0.001% and S: 0.0009%.

[0076] Comparative Example 2

[0077] A method for preparing red copper comprises the following steps:

[0078] (1) performing semi-continuous casting on copper to obtain a cast billet, then heating the cast billet at 840° C. for 6 hours and then hot rolling it, and finally performing face milling to obtain hot-rolled copper; the temperature of the semi-continuous casting is 1158° C., the pulling rate of the semi-continuous casting is 120 mm / min; the temperature of the hot rolling is 840° C., the total deformation of the hot rolling is 85%, and the number of hot rolling passes is 7;

[0079] (2) the hot-rolled copper obtained in step (1) is subjected to preliminary rolling, brushing, finished product rolling, unwinding and bell-type annealing in sequence to obtain annealed copper; the total deformation of the preliminary rolling is 80%, the number of preliminary rolling passes is 6, and the preliminary rolling is cold rolling; the total deformation of the finished product rolling is 70%, the number of finished product rolling passes is 6, and the finished product rolling is cold rolling; the temperature of the bell-type annealing is 470° C., and the holding time of the bell-type annealing is 8 hours;

[0080] (3) pickling the annealed copper obtained in step (2) to obtain copper; the pickling method is immersion pickling, the pickling speed is 22 m / min, the concentration of the acid solution during pickling is 28 wt.%, the acid in the acid solution is sulfuric acid, the concentration of the passivation solution during pickling is 0.021 wt.%, and the passivation agent in the passivation solution is HC-09 passivation agent produced by Hangzhou Baimu Surface Technology Co., Ltd.

[0081] The red copper prepared in Comparative Example 2 has the following chemical compositions by mass percentage: Cu+Ag: 99.983%, Bi: 0.0009%, Sb: 0.0007%, As: 0.0012%, Fe: 0.0014%, Pb: 0.0011% and S: 0.0012%.

[0082] The properties of the copper prepared in Examples 1 to 4 and Comparative Examples 1 to 2 were tested, and the results are shown in Table 1:

[0083] Table 1 Properties of the copper prepared in Examples 1 to 4 and Comparative Examples 1 to 2

[0084] Tensile strength / MPa <![CDATA[Elongation A 11.3 / %]]> Hardness / HV Surface tension coefficient / dyn / cm Comparative Example 1 244 40 65 28 Comparative Example 2 235 42 61 30 Example 1 239 41 62 40 Example 2 241 40 62 40 Example 3 242 41 65 40 Example 4 236 41 62 40

[0085] In Table 1, the test method for tensile strength is: GB / T 34505-2017 room temperature tensile test method;

[0086] The test method for elongation is: GB / T 34505-2017 room temperature tensile test method;

[0087] The test method for hardness is: GB / T 4340.1 Metallic materials Vickers hardness test Part 1 Test method;

[0088] The test method for surface tension coefficient is: GB / T 232 Metal Material Bending Test Method.

[0089] It can be seen from Table 1 that the copper prepared by the present invention has higher tensile strength, hardness and elongation, and the surface tension coefficient can reach 40 dyn / cm; at the same time, through the comparison between the embodiment and the comparative example, it can be seen that the present invention can significantly improve the surface tension of copper by optimizing the process parameters during pickling.

[0090] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing high surface tension copper, comprising the following steps: (1) semi-continuously casting and hot rolling copper in sequence to obtain hot-rolled copper; (2) subjecting the hot-rolled copper obtained in step (1) to initial rolling, finished product rolling and bell-type annealing in sequence to obtain annealed copper; (3) pickling the annealed copper obtained in step (2) to obtain high surface tension copper; The pickling speed is 10-20 m / min; the concentration of the acid solution during pickling is 10-25 wt.%, and the concentration of the passivation solution during pickling is 0.025-0.07 wt.%.

2. The preparation method according to claim 1, characterized in that: The temperature of the semi-continuous casting in the step (1) is 1150-1200° C., and the pulling rate of the semi-continuous casting is 60-140 mm / min.

3. The preparation method according to claim 1, characterized in that: In the step (1), the hot rolling temperature is 800-950° C., the total deformation of the hot rolling is 80-95%, and the number of hot rolling passes is 7-11.

4. The preparation method according to claim 1, characterized in that: The total deformation amount of the initial rolling in the step (2) is 40-95%, and the initial rolling is cold rolling.

5. The preparation method according to claim 1, characterized in that: The total deformation of the finished product during rolling in step (2) is 40-80%, and the finished product is rolled by cold rolling.

6. The preparation method according to claim 1, characterized in that: The temperature of the bell-jar annealing in the step (2) is 400-530° C., and the holding time of the bell-jar annealing is 7-13 hours.

7. The preparation method according to claim 1, characterized in that: The acid in the acid solution in step (3) is sulfuric acid.

8. The preparation method according to claim 1, characterized in that: The pickling speed in the step (3) is 12 to 18 m / min; the concentration of the acid solution during pickling is 12 to 22 wt.%, and the concentration of the passivation solution during pickling is 0.03 to 0.065 wt.%.

9. Red copper with high surface tension prepared by the preparation method according to any one of claims 1 to 8.

10. The high surface tension copper according to claim 9, characterized in that: Measured by mass percentage, the chemical composition of the high surface tension copper includes: Cu+Ag≥99.90%, Bi≤0.001%, Sb≤0.002%, As≤0.002%, Fe≤0.005%, Pb≤0.005% and S≤0.005%.