阅读说明：本技术 一种高纯铜的成型加工方法 (Forming processing method of high-purity copper ) 是由 韦建敏 张晓蓓 张小波 刘正斌 于 2021-08-19 设计创作，主要内容包括：本发明公开了一种高纯铜的成型加工方法。解决了现有技术中通过PCB废液制备出的铜纯度不高、利用率不高的技术问题。它包括下述步骤：(1)剪切；(2)真空熔炼；(3)浇注；(4)挤压；(5)拉伸；(6)矫直；(7)退火,得到高纯铜成品。本发明将纯度99.99%的阴极铜进一步通过真空熔炼、挤压、退火可以得到高纯无氧铜产品,使得到的铜成品的纯度在99.995%以上,氧含量控制在3ppm以下。(The invention discloses a forming processing method of high-purity copper. The technical problems that the purity of copper prepared by the PCB waste liquid is not high and the utilization rate is not high in the prior art are solved. It comprises the following steps: (1) shearing; (2) vacuum smelting; (3) pouring; (4) extruding; (5) stretching; (6) straightening; (7) and annealing to obtain a high-purity copper finished product. The invention can obtain high-purity oxygen-free copper products by further carrying out vacuum melting, extrusion and annealing on cathode copper with the purity of 99.99 percent, so that the purity of the obtained copper finished products is more than 99.995 percent, and the oxygen content is controlled to be less than 3 ppm.)

1. The forming processing method of the high-purity copper is characterized by comprising the following steps of:

(1) shearing the cathode copper by using a plate shearing machine;

(2) smelting in a vacuum smelting furnace, and vacuumizing to a vacuum degree of less than or equal to 2 × 10^-2Pa, the smelting temperature is 1150-1250 ℃; heating to melt and then preserving heat for 0.5-1 h; in a vacuum melting furnaceVacuum degree of less than or equal to 2 x 10^-2Pa, cooling to solidify the melt to fully remove the gas and obtain a copper solidified body; refining the copper solidified body, heating to 500-650 ℃ at a heating rate of 15-25 ℃/h, and preserving heat for 0.5-1 h; then heating to 700-850 ℃ at a heating rate of 15-25 ℃/h, and preserving heat for 0.5-1 h; continuously heating to 900-1050 ℃ at the heating rate of 25-35 ℃/h, and preserving the heat for 1-2 h; then heating to 1100-1300 ℃ at a heating rate of 35-45 ℃/h, and preserving heat for 1-2 h to obtain refined copper melt;

(3) transferring the refined copper melt subjected to vacuum melting into a heat preservation furnace, distributing copper liquid to each crystallizer through the heat preservation furnace, and solidifying and forming the copper liquid in the crystallizer to obtain a copper bar blank;

(4) extruding the copper bar blank by using a continuous extruder, wherein the extrusion temperature is 550-750 ℃, the extrusion force is 5-40 MN, and the residual thickness is controlled to be 5-20 mm; obtaining an extrusion blank;

(5) stretching the extrusion blank by adopting a hydraulic drawing machine to obtain a semi-finished product;

(6) straightening the stretched semi-finished copper bar by using a two-roller straightening machine;

(7) and (3) performing stress relief annealing on the stretched semi-finished copper bar, wherein the annealing temperature is 200-300 ℃, and the heat preservation time is 4-10 hours, so as to obtain a high-purity copper finished product.

2. The forming method of high-purity copper according to claim 1, wherein the heating temperature in the step (2) is 1150 to 1450 ℃.

3. The method for forming high-purity copper according to claim 1, wherein the heating temperature in the step (2) is 1400 ℃.

4. The forming processing method of high-purity copper according to claim 1, wherein in the step (4), the extrusion temperature is 600-700 ℃, the extrusion force is 10-30 MN, and the residual thickness is controlled to be 10-15 mm.

5. The forming processing method of high-purity copper according to claim 1, wherein in the step (4), the extrusion temperature is 650 ℃, the extrusion force is 2MN, and the residual thickness is controlled to be 10-15 mm.

6. The forming method of high-purity copper according to claim 1, wherein in the step (7), the annealing temperature is 220 to 280 ℃ and the holding time is 6 to 8 hours.

7. The method for forming high-purity copper according to claim 1, wherein in the step (7), the annealing temperature is 250 ℃ and the holding time is 7 hours.

Technical Field

The invention belongs to the field of waste liquid recycling, and particularly relates to a forming processing method of high-purity copper.

Background

PCB, i.e. printed circuit board, manufacturing technology is a very complex and comprehensive process technology. A qualified PCB is subjected to the processing processes of copper deposition, electroplating, developing, etching and the like, various heavy metal wastewater and organic wastewater are discharged in the processing process, the components are complex, and the processing difficulty is high. Calculated according to the utilization rate of the PCB copper foil of 30-40%, the copper content in the waste liquid and the waste water is considerable. Calculated according to ten thousand square meters of double-sided boards (the thickness of each copper foil is 35 microns), the copper content in the waste liquid and the waste water is about 4500 kilograms, and other heavy metals and noble metals are contained. The metal in the waste liquid and the waste water is discharged without being treated, which causes waste and pollutes the environment.

In the prior art, the electrolytic method is adopted for treating the PCB waste liquid to recover the copper in the PCB waste liquid, but in the prior art, the waste liquid is directly introduced into an electrolytic cell for electrolysis, a plurality of large-particle impurities in the waste liquid are not pretreated, the electrolysis efficiency is influenced, and meanwhile, the impurities in the waste liquid can pollute the environment. In addition, the copper prepared by recovery in the prior art has low purity and low utilization rate.

Disclosure of Invention

The invention aims to provide a forming processing method of high-purity copper. The technical problems that the purity of copper prepared by the PCB waste liquid is not high and the utilization rate is not high in the prior art are solved.

In order to achieve the purpose, the invention provides the following technical scheme:

the invention provides a forming processing method of high-purity copper, which comprises the following steps:

(1) shearing the cathode copper by using a plate shearing machine;

(2) smelting in a vacuum smelting furnace, and vacuumizing to a vacuum degree of less than or equal to 2 × 10^-2Pa, the smelting temperature is 1150-1250 ℃; heating to melt and then preserving heat for 0.5-1 h; keeping the vacuum degree in the vacuum melting furnace less than or equal to 2 multiplied by 10^-2Pa, cooling to solidify the melt to fully remove the gas and obtain a copper solidified body; refining the copper solidified body, heating to 500-650 ℃ at a heating rate of 15-25 ℃/h, and preserving heat for 0.5-1 h; then heating to 700-850 ℃ at a heating rate of 15-25 ℃/h, and preserving heat for 0.5-1 h; continuously heating to 900-1050 ℃ at the heating rate of 25-35 ℃/h, and preserving the heat for 1-2 h; then heating to 1100-1300 ℃ at a heating rate of 35-45 ℃/h, and preserving heat for 1-2 h to obtain refined copper melt;

(3) transferring the copper liquid after vacuum melting into a heat preservation furnace, distributing the copper liquid to each crystallizer through the heat preservation furnace, and solidifying and forming the copper liquid in the crystallizer to obtain a copper bar blank;

(4) extruding the copper bar blank by using a continuous extruder, wherein the extrusion temperature is 550-750 ℃, the extrusion force is 5-40 MN, and the residual thickness is controlled to be 5-20 mm; obtaining an extrusion blank;

(5) stretching the extrusion blank by adopting a hydraulic drawing machine to obtain a semi-finished product;

(6) straightening the stretched semi-finished copper bar by using a two-roller straightening machine;

(7) and (3) performing stress relief annealing on the stretched semi-finished copper bar, wherein the annealing temperature is 200-300 ℃, and the heat preservation time is 4-10 hours, so as to obtain a high-purity copper finished product.

Further, in the step (2), the heating temperature is 1150-1450 ℃.

Further, in the step (2), the heating temperature is 1400 ℃.

Further, in the step (4), the extrusion temperature is 600-700 ℃, the extrusion force is 10-30 MN, and the residual thickness is controlled to be 10-15 mm.

Further, in the step (4), the extrusion temperature is 650 ℃, the extrusion force is 2MN, and the residual thickness is controlled to be 10-15 mm.

Further, in the step (7), the annealing temperature is 220-280 ℃, and the heat preservation time is 6-8 hours.

Further, in the step (7), the annealing temperature is 250 ℃, and the heat preservation time is 7 hours.

Based on the technical scheme, the embodiment of the invention can at least produce the following technical effects:

according to the forming processing method of the high-purity copper, provided by the invention, 99.99% of cathode copper is further subjected to continuous casting procedures under vacuum conditions such as vacuum melting, extrusion, annealing and the like, so that the oxygen content in a high-purity copper product is controlled to be below 3ppm, and the special material requirements of electronic industries such as electric vacuum devices and the like are met.

Detailed Description

First, preparation example:

example 1:

a forming processing method of high-purity copper comprises the following steps:

(1) shearing cathode copper with the purity of 99.99% by using a plate shearing machine;

(2) smelting in a vacuum smelting furnace, and vacuumizing to 2X 10^-2Pa, the smelting temperature is 1200 ℃; heating to melt, and keeping the temperature for 0.8 h; maintaining the degree of vacuum in the vacuum melting furnace at 2X 10^-2Pa, cooling to solidify the melt to fully remove the gas and obtain a copper solidified body; refining the copper solidified body, heating to 580 ℃ at the heating rate of 20 ℃/h, and preserving heat for 0.8 h; then heating to 780 ℃ at the heating rate of 20 ℃/h and preserving heat for 0.8 h; continuously heating to 980 ℃ at the heating rate of 30 ℃/h and preserving heat for 1.5 h; then heating to 1200 ℃ at the heating rate of 40 ℃/h, and preserving the heat for 1.5h to obtain refined copper melt;

(3) transferring the refined copper melt subjected to vacuum melting into a heat preservation furnace, distributing copper liquid to each crystallizer through the heat preservation furnace, and solidifying and forming the copper liquid in the crystallizer to obtain a copper bar blank;

(4) extruding the copper bar blank by a continuous extruder at the extrusion temperature of 650 ℃, wherein the extrusion force is 20MN, and the residual thickness is controlled at 12 mm; obtaining an extrusion blank;

(5) stretching the extrusion blank by adopting a hydraulic drawing machine to obtain a semi-finished product;

(6) straightening the stretched semi-finished copper bar by using a two-roller straightening machine;

(7) and (3) performing stress relief annealing on the stretched semi-finished copper bar, wherein the annealing temperature is 250 ℃, and the heat preservation time is 7 hours, so as to obtain a high-purity copper finished product.

Example 2:

a forming processing method of high-purity copper comprises the following steps:

(1) shearing cathode copper with the purity of 99.99% by using a plate shearing machine;

(2) smelting in a vacuum smelting furnace, and vacuumizing to 2X 10^-2Pa, the smelting temperature is 1250 ℃; heating to melt, and keeping the temperature for 0.5 h; maintaining the degree of vacuum in the vacuum melting furnace at 2X 10^-2Pa, decreaseSolidifying the melt at a high temperature to fully degas and obtain a copper solidified body; refining the copper solidified body, heating to 650 ℃ at a heating rate of 25 ℃/h, and keeping the temperature for 0.5 h; then heating to 850 ℃ at the heating rate of 25 ℃/h and preserving the heat for 0.5 h; continuously heating to 1050 ℃ at the heating rate of 35 ℃/h and preserving the heat for 1 h; then heating to 1300 ℃ at the heating rate of 45 ℃/h, and preserving the heat for 1h to obtain refined copper melt;

(3) transferring the refined copper melt subjected to vacuum melting into a heat preservation furnace, distributing copper liquid to each crystallizer through the heat preservation furnace, and solidifying and forming the copper liquid in the crystallizer to obtain a copper bar blank;

(4) extruding the copper bar blank by a continuous extruder at the extrusion temperature of 750 ℃ and the extrusion pressure of 5MN, and controlling the residual thickness of the extrusion to be 20 mm; obtaining an extrusion blank;

(5) stretching the extrusion blank by adopting a hydraulic drawing machine to obtain a semi-finished product;

(6) straightening the stretched semi-finished copper bar by using a two-roller straightening machine;

(7) and (3) performing stress relief annealing on the stretched semi-finished copper bar at the annealing temperature of 300 ℃ for 4h to obtain a high-purity copper finished product.

Example 3:

a forming processing method of high-purity copper comprises the following steps:

(1) shearing cathode copper with the purity of 99.99% by using a plate shearing machine;

(2) smelting in a vacuum smelting furnace, and vacuumizing to a vacuum degree of 1.5 multiplied by 10^-2Pa, the smelting temperature is 1150 ℃; heating to melt and then preserving heat for 1 h; maintaining the degree of vacuum in the vacuum melting furnace at 1.5X 10^-2Pa, cooling to solidify the melt to fully remove the gas and obtain a copper solidified body; refining the copper solidified body, heating to 500 ℃ at a heating rate of 15 ℃/h, and preserving heat for 1 h; then heating to 700 ℃ at the heating rate of 15 ℃/h and preserving the heat for 1 h; continuously heating to 900 ℃ at the heating rate of 25 ℃/h and preserving the heat for 2 h; then heating to 1100 ℃ at the heating rate of 35 ℃/h, and preserving the heat for 2h to obtain refined copper melt;

(3) transferring the refined copper melt subjected to vacuum melting into a heat preservation furnace, distributing copper liquid to each crystallizer through the heat preservation furnace, and solidifying and forming the copper liquid in the crystallizer to obtain a copper bar blank;

(4) extruding the copper bar blank by a continuous extruder at the extrusion temperature of 550 ℃, wherein the extrusion force is 40MN, and the residual thickness is controlled to be 5 mm; obtaining an extrusion blank;

(5) stretching the extrusion blank by adopting a hydraulic drawing machine to obtain a semi-finished product;

(6) straightening the stretched semi-finished copper bar by using a two-roller straightening machine;

(7) and (3) performing stress relief annealing on the stretched semi-finished copper bar at the annealing temperature of 200 ℃ for 10 hours to obtain a high-purity copper finished product.

Example 4:

a forming processing method of high-purity copper comprises the following steps:

(1) shearing cathode copper with the purity of 99.99% by using a plate shearing machine;

(2) smelting in a vacuum smelting furnace, and vacuumizing to the vacuum degree of 1 × 10^-2Pa, the smelting temperature is 1230 ℃; heating to melt, and keeping the temperature for 0.6 h; maintaining the degree of vacuum in the vacuum melting furnace at 1X 10^-2Pa, cooling to solidify the melt to fully remove the gas and obtain a copper solidified body; refining the copper solidified body, heating to 620 ℃ at a heating rate of 18 ℃/h, and preserving heat for 0.6 h; then heating to 750 ℃ at the heating rate of 18 ℃/h and preserving the heat for 0.8 h; continuously heating to 950 ℃ at the heating rate of 28 ℃/h and preserving the heat for 2 h; then heating to 1250 ℃ at the heating rate of 38 ℃/h, and preserving the heat for 1.5h to obtain refined copper melt;

(3) transferring the refined copper melt subjected to vacuum melting into a heat preservation furnace, distributing copper liquid to each crystallizer through the heat preservation furnace, and solidifying and forming the copper liquid in the crystallizer to obtain a copper bar blank;

(4) extruding the copper bar blank by a continuous extruder at the extrusion temperature of 700 ℃, wherein the extrusion force is 15MN, and the residual thickness is controlled to be 10 mm; obtaining an extrusion blank;

(5) stretching the extrusion blank by adopting a hydraulic drawing machine to obtain a semi-finished product;

(6) straightening the stretched semi-finished copper bar by using a two-roller straightening machine;

(7) and (3) performing stress relief annealing on the stretched semi-finished copper bar, wherein the annealing temperature is 220 ℃, and the heat preservation time is 8 hours, so as to obtain a high-purity copper finished product.

Example 5:

a forming processing method of high-purity copper comprises the following steps:

(1) shearing cathode copper with the purity of 99.99% by using a plate shearing machine;

(2) smelting in a vacuum smelting furnace, and vacuumizing to a vacuum degree of 1.3 multiplied by 10^-2Pa, the smelting temperature is 1200 ℃; heating to melt and then preserving heat for 1 h; maintaining the degree of vacuum in the vacuum melting furnace at 1.3X 10^-2Pa, cooling to solidify the melt to fully remove the gas and obtain a copper solidified body; refining the copper solidified body, heating to 650 ℃ at a heating rate of 20 ℃/h, and preserving heat for 0.5 h; then heating to 750 ℃ at the heating rate of 20 ℃/h and preserving the heat for 1 h; continuously heating to 1000 ℃ at the heating rate of 30 ℃/h and preserving heat for 1.5 h; then heating to 1200 ℃ at the heating rate of 40 ℃/h, and preserving the heat for 1.5h to obtain refined copper melt;

(3) transferring the refined copper melt subjected to vacuum melting into a heat preservation furnace, distributing copper liquid to each crystallizer through the heat preservation furnace, and solidifying and forming the copper liquid in the crystallizer to obtain a copper bar blank;

(4) extruding the copper bar blank by a continuous extruder at the extrusion temperature of 600 ℃, wherein the extrusion force is 30MN, and the residual thickness is controlled to be 15 mm; obtaining an extrusion blank;

(5) stretching the extrusion blank by adopting a hydraulic drawing machine to obtain a semi-finished product;

(6) straightening the stretched semi-finished copper bar by using a two-roller straightening machine;

(7) and (4) performing stress relief annealing on the stretched semi-finished copper bar, wherein the annealing temperature is 280 ℃, and the heat preservation time is 6 hours, so as to obtain a high-purity copper finished product.

Example 6:

a forming processing method of high-purity copper comprises the following steps:

(1) shearing cathode copper with the purity of 99.99% by using a plate shearing machine;

(2) smelting in a vacuum smelting furnace and vacuumizingVacuum to vacuum degree of 1.8X 10^-2Pa, the smelting temperature is 1180 ℃; heating to melt and then preserving heat for 1 h; maintaining the degree of vacuum in the vacuum melting furnace at 1.8X 10^-2Pa, cooling to solidify the melt to fully remove the gas and obtain a copper solidified body; refining the copper solidified body, heating to 620 ℃ at a heating rate of 22 ℃/h, and preserving heat for 0.6 h; then heating to 820 ℃ at the heating rate of 22 ℃/h, and preserving the heat for 0.8 h; continuously heating to 1020 ℃ at the heating rate of 32 ℃/h and preserving heat for 2 h; then heating to 1280 ℃ at the heating rate of 42 ℃/h, and preserving heat for 1.5h to obtain refined copper melt;

(3) transferring the refined copper melt subjected to vacuum melting into a heat preservation furnace, distributing copper liquid to each crystallizer through the heat preservation furnace, and solidifying and forming the copper liquid in the crystallizer to obtain a copper bar blank;

(4) extruding the copper bar blank by adopting a continuous extruder, wherein the extrusion temperature is 610 ℃, the extrusion force is 28MN, and the residual thickness is controlled to be 12 mm; obtaining an extrusion blank;

(5) stretching the extrusion blank by adopting a hydraulic drawing machine to obtain a semi-finished product;

(6) straightening the stretched semi-finished copper bar by using a two-roller straightening machine;

(7) and (4) performing stress relief annealing on the stretched semi-finished copper rod, wherein the annealing temperature is 270 ℃, and the heat preservation time is 6.5 hours, so as to obtain a high-purity copper finished product.

Example 7:

a forming processing method of high-purity copper comprises the following steps:

(1) shearing cathode copper with the purity of 99.99% by using a plate shearing machine;

(2) smelting in a vacuum smelting furnace, and vacuumizing to a vacuum degree of 1.4 multiplied by 10^-2Pa, the smelting temperature is 1250 ℃; heating to melt and then preserving heat for 1 h; maintaining the degree of vacuum in the vacuum melting furnace at 1.4X 10^-2Pa, cooling to solidify the melt to fully remove the gas and obtain a copper solidified body; refining the copper solidified body, heating to 650 ℃ at a heating rate of 25 ℃/h, and keeping the temperature for 0.5 h; then heating to 850 ℃ at the heating rate of 25 ℃/h and preserving the heat for 1 h; continuously heating to 900 ℃ at the heating rate of 35 ℃/h and preserving the heat for 2 h; then heating to 1300 ℃ at the heating rate of 35 ℃/h and preserving the heat for 1h, obtaining refined copper melt;

(3) transferring the refined copper melt subjected to vacuum melting into a heat preservation furnace, distributing copper liquid to each crystallizer through the heat preservation furnace, and solidifying and forming the copper liquid in the crystallizer to obtain a copper bar blank;

(4) extruding the copper bar blank by using a continuous extruder, wherein the extrusion temperature is 710 ℃, the extrusion force is 15MN, and the residual thickness is controlled to be 20 mm; obtaining an extrusion blank;

(5) stretching the extrusion blank by adopting a hydraulic drawing machine to obtain a semi-finished product;

(6) straightening the stretched semi-finished copper bar by using a two-roller straightening machine;

(7) and (3) performing stress relief annealing on the stretched semi-finished copper rod, wherein the annealing temperature is 290 ℃, and the heat preservation time is 5 hours, so as to obtain a high-purity copper finished product.

Second, Experimental example

1. The purity and oxygen content of the high purity copper products obtained in examples 1 to 7 were measured using "grade and chemical composition of processed copper and copper alloys" (GB5231-2012) C10100(TU00), and the results are shown in table 1 below:

table 1 results of purity and oxygen content measurements in examples 1-7

The above disclosure is only for the purpose of illustrating the preferred embodiments of the present invention, and it is therefore to be understood that the invention is not limited by the scope of the appended claims.