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CN-121988612-A - Manufacturing method and product of rolled copper foil for 448G high-speed cable

CN121988612ACN 121988612 ACN121988612 ACN 121988612ACN-121988612-A

Abstract

The invention provides a method for elongating the grain structure of a rolled copper foil for 448G high-speed cables and the rolled copper foil for 448G high-speed cables prepared by the method. The method comprises the steps of carrying out multi-pass cold rolling on a copper strip blank to enable the total rolling reduction to be more than 99.6% and finally rolled to be 6-35 mu m, setting a differential rolling main section at the rear section of cold rolling, wherein the differential rolling main section starts from the accumulated rolling reduction of 55-60% and continues to finish to the thickness, carrying out differential rolling in the differential rolling main section by adopting a linear velocity ratio of 1.22-1.28, carrying out short-time sectional annealing twice in the cold rolling process, and controlling the strip after the sectional annealing to be in a non-complete recrystallization state, wherein the volume fraction of recrystallization is not higher than 10%. The method can obtain the rolled copper foil structure for 448G high-speed cables, wherein crystal grains are continuously distributed along the rolling direction, and the aspect ratio of the crystal grains is high.

Inventors

  • SHEN XIAOXIA
  • SHEN GUOZHONG

Assignees

  • 杭州巨力绝缘材料有限公司

Dates

Publication Date
20260508
Application Date
20260319

Claims (20)

  1. 1. A method for manufacturing a rolled copper foil for 448G high-speed cables is characterized by comprising the following steps: S1) providing a copper strip blank and carrying out surface cleaning pretreatment; s2) carrying out multi-pass cold rolling on the copper strip blank to ensure that the total reduction rate is more than or equal to 99.6%, and finally rolling to the target thickness of 6-35 mu m; s3) setting a differential rolling main section in the cold rolling rear section, wherein the differential rolling main section starts from 55-60% of accumulated rolling reduction and ends to a final thickness, and differential rolling is carried out in the differential rolling main section at a linear speed ratio i of 1.22-1.28; S4) carrying out two short-time sectional annealing heat treatments in the cold rolling process, wherein the first sectional annealing is arranged before entering the differential rolling main section, and the second sectional annealing is arranged in the differential rolling main section; S5) controlling the recrystallization volume fraction of the strip after the sectional annealing to be less than or equal to 10 percent, and continuously rolling to the target thickness to obtain the rolled copper foil.
  2. 2. The method for producing a rolled copper foil for 448G high speed cables according to claim 1, wherein the target thickness is 6 to 12 μm.
  3. 3. The method for producing a rolled copper foil for 448G high speed cables according to claim 1, wherein said differential rolling main section starts from an integrated reduction of 55-60% and continues to end to a final thickness.
  4. 4. The method for producing a rolled copper foil for 448G high speed cables according to claim 1, wherein the linear velocity ratio i is a ratio of work roll linear velocities, i=v fast roll/V slow roll, and i is 1.22 to 1.28.
  5. 5. The method for producing a rolled copper foil for 448G high speed cables according to claim 1, wherein the differential rolling pass in the cold rolling back-end pass is not less than 70%.
  6. 6. The method for producing a rolled copper foil for 448G high-speed cables according to claim 1, wherein after entering the differential rolling main section, the linear velocity ratio i is controlled stepwise constant, and the fluctuation of i in the differential rolling main section is not more than ±0.02.
  7. 7. The method for producing a rolled copper foil for 448G high speed cables according to claim 1, wherein the trigger point of the first stage annealing is 45-55% of the cumulative reduction, the annealing temperature is 370-390 ℃, and the equivalent holding time is 40-80 s.
  8. 8. The method for producing a rolled copper foil for 448G high speed cables according to claim 1, wherein the trigger point of the second stage annealing is 70-80% of the cumulative reduction, the annealing temperature is 360-380 ℃, and the equivalent holding time is 30-60 s.
  9. 9. The method for manufacturing a rolled copper foil for 448G high speed cables according to claim 1, wherein the segment annealing is performed under an atmosphere of N 2 or N 2 /H 2 .
  10. 10. The method for producing a rolled copper foil for 448G high speed cables according to claim 1, wherein the recrystallized volume fraction of the strip after the segment annealing is 8% or less.
  11. 11. The method for manufacturing a rolled copper foil for 448G high speed cables according to claim 1, wherein the inlet/outlet tension of the rear section of the thin foil is increased by 30 to 60% with respect to the front/middle section.
  12. 12. The method for producing a rolled copper foil for 448G high speed cables according to claim 1, wherein the final 2-3 passes of the final rolling maintains a linear velocity ratio i of 1.24 or more.
  13. 13. The rolled copper foil for 448G high speed cables according to any one of claim 1 to 12, wherein the aspect ratio AR of the crystal grains is not less than 24.
  14. 14. The rolled copper foil according to claim 13, wherein the crystal grains of the rolled copper foil are continuously distributed in the rolling direction.
  15. 15. The rolled copper foil of claim 13 or 14, wherein the beta-fiber related texture fraction is 70% to 78%.
  16. 16. The rolled copper foil according to claim 13 or 14, wherein the dislocation density ρ is (4-8). Times.101 4 m-2.
  17. 17. A rolled copper foil is characterized in that the thickness of the copper foil is 6-12 mu m, the recrystallization volume fraction of the copper foil in a non-complete recrystallization state is not higher than 10%, the aspect ratio AR of crystal grains is more than or equal to 24, and the crystal grains of the copper foil are continuously distributed along the rolling direction.
  18. 18. The rolled copper foil according to claim 17, wherein the recrystallized volume fraction of the copper foil is not higher than 10%, preferably not higher than 8%.
  19. 19. The rolled copper foil of claim 17, wherein the copper foil has a beta-fiber related texture fraction of 70% to 78%.
  20. 20. The rolled copper foil according to claim 17, wherein the copper foil has a dislocation density ρ of (4-8) x 101 4 m-2 and a low angle grain boundary length fraction or area fraction of 40% or more.

Description

Manufacturing method and product of rolled copper foil for 448G high-speed cable Technical Field The invention relates to a method for realizing elongation of copper foil grains along a rolling direction through cooperative control of differential rolling and sectional annealing and a rolled copper foil product for 448G high-speed cables, which are prepared by the method, can realize that crack initiation of a metal foil in a flanging and lap joint area is inhibited in a high-speed coating process on the premise of not reducing the coating line speed and not increasing the thickness of the metal foil, and are mainly used for manufacturing the rolled copper foil for 448G high-speed cables, and belong to the technical fields of high-speed data transmission and metal material processing. Background The conventional rolled copper foil for 448G high-speed cables generally adopts a symmetrical cold rolling, and refines grains or stretches to some extent in the rolling direction by increasing the rolling reduction. However, such deformation is still mainly represented by plane strain, grains are easy to collapse and split, and recrystallization is easy to occur to a higher degree in the subsequent annealing process, so that the elongated structure formed by cold rolling is weakened or equiaxed, and it is difficult to stably obtain a high-aspect ratio grain structure continuously distributed along the rolling direction in the finished ultrathin copper foil. Therefore, the existing copper foil is difficult to be used for manufacturing the high-speed cable shielding composite copper foil. Disclosure of Invention The design objective is to provide a method for elongating the grain structure of a rolled copper foil for 448G high-speed cables, which is characterized in that the total rolling reduction is more than 99.6% in multi-pass cold rolling, a differential rolling main section is arranged in a section where the accumulated rolling reduction of the rear section of the cold rolling is 55-60% and the final thickness is finished, the differential rolling is carried out in the main section by adopting a linear speed ratio of 1.22-1.28, and two short-time sectional annealing is combined to inhibit complete recrystallization, so that the stability and the repeatability of the formation of the grain structure with high aspect ratio, which is continuously distributed along the rolling direction, are improved. The invention also provides a rolled copper foil product for 448G high-speed cables, wherein crystal grains of the rolled copper foil for 448G high-speed cables are continuously distributed along the rolling direction and have a higher crystal grain length-width ratio in a non-completely recrystallized state. Preferably, the 448G high-speed cable-use rolled copper foil has a recrystallized volume fraction of not more than 10%. The method comprises the following steps of carrying out multi-pass cold rolling on a copper strip blank to enable the total rolling reduction to reach more than 99.6% and finally roll to a target thickness, setting a differential rolling main section at the cold rolling rear section, carrying out differential rolling in the main section by adopting a linear speed ratio of 1.22-1.28 from the accumulated rolling reduction of 55-60% to the end of the final thickness, introducing continuous shearing deformation into the material, carrying out two short-time sectional anneals in the cold rolling process, wherein the first sectional anneals are arranged in the differential rolling main section before entering the differential rolling main section, the second sectional anneals are arranged in the differential rolling main section, and controlling the strip after the sectional anneals to be in a non-complete recrystallization state. By the control of the process, the material structure evolution is mainly deformation structure maintenance, dislocation recovery and limited recrystallization, and is favorable for obtaining the rolled copper foil structure for 448G high-speed cables, wherein crystal grains are continuously distributed along the rolling direction, and the aspect ratio of the crystal grains is high. The rolled copper foil for 448G high-speed cables obtained by the method of the invention can show the following structural characteristics: (1) Under the actions of higher total rolling reduction and rear-stage differential rolling, crystal grains are continuously distributed along the rolling direction, and the aspect ratio of the crystal grains is higher; (2) The density of the transverse high-angle grain boundaries in the tissue is relatively reduced, and the proportion of the low-angle grain boundaries is relatively increased; (3) The tissue may coexist with a higher dislocation density and a stronger β -fiber related texture; (4) The above tissue characteristics can be evaluated by EBSD reconstruction, recrystallization volume fraction statistics, texture fraction statistics, and dislocati