A production method of an aluminum foil substrate for copper plating of a PCB copper-aluminum composite foil

Abstract

The application provides a production method of an aluminum foil substrate for PCB copper-aluminum composite foil copper plating, which comprises the following steps: (1) sequentially performing melting and casting-rolling processes on an aluminum alloy to obtain a blank with a thickness of 6-7 mm; (2) performing an annealing process after cold rolling the blank to 3-4 mm; in the annealing process, first, the temperature is raised to 100-120 DEG C, and then the temperature is kept for 6-12 h; then, the temperature is raised to 500-600 DEG C within 30-60 min, and then the temperature is kept for 2-6 h; (3) performing an annealing process after continuously cold rolling to a thickness of 0.5-1 mm; in the annealing process, first, the temperature is raised to 320-400 DEG C, and then the temperature is kept for 3-5 h; (4) performing a straightening and cutting process after continuously cold rolling to a thickness of 0.02-0.4 mm, to obtain the aluminum foil substrate. The aluminum foil substrate produced by the production method has good surface quality and few pinholes, and is suitable for producing PCB copper-aluminum composite foil.

Description

TECHNICAL FIELD

[0001] The application relates to an aluminum foil production method, in particular to an aluminum foil base material production method for copper plating of a PCB copper-aluminum composite foil. BACKGROUND

[0002] PCB, also known as a printed circuit board, is an important electronic component, is a support body of electronic components, and is a carrier for electrical connection of electronic components. Aluminum foil is widely used on various circuit boards due to excellent performance in electromagnetic shielding, heat dissipation and current collector, etc. At present, there are many aluminum foil production processes on the market. For example, a method for preparing an aluminum foil for a PCB by using a cast-rolling blank is disclosed in Chinese patent CN104550235A, and a production process of a thick aluminum foil for a PCB is disclosed in Chinese patent CN116637933A.

[0003] In the field of electronic applications, in order to increase the conductivity and solderability of aluminum, it is necessary to electroplate copper and tin and other metals on the surface thereof. However, the existing aluminum foil production process has many pinholes in the aluminum foil base material, poor surface quality, and seriously affects the quality of the subsequent copper-aluminum composite foil.

[0004] In order to solve the above problems, people have been seeking an ideal technical solution. SUMMARY

[0005] The purpose of the present application is to overcome the shortcomings of the prior art and provide a PCB copper-aluminum composite foil copper plating aluminum foil base material production method.

[0006] In order to achieve the above purpose, the technical scheme adopted by the present application is:

[0007] A PCB copper-aluminum composite foil copper plating aluminum foil base material production method comprises the following steps:

[0008] (1) sequentially performing melting and cast-rolling processes on an aluminum alloy to obtain a blank with a thickness of 6-7 mm;

[0009] (2) cold-rolling the blank to 3-4 mm and then performing an annealing process; in the annealing process, first heat to 100-120 DEG C, keep for 6-12 h, then heat to 500-600 DEG C within 30-60 min, and then keep for 2-6 h;

[0010] (3) continuing to cold-roll to a thickness of 0.5-1 mm and then performing an annealing process; in the annealing process, first heat to 320-400 DEG C, and then keep for 3-5 h;

[0011] (4) continuing to cold-roll to a thickness of 0.02-0.4 mm, and then performing a straightening and cutting process to obtain an aluminum foil base material.

[0012] The aluminum alloy component is: Si: 0.04-0.25%, Fe: 0.25-0.45%, Cu: 0.01-0.05%, Mn: 0-0.01%, Mg: 0.005-0.02%, Zn: 0-0.01%, Ti: 0.001-0.03%, and the balance is aluminum; the sum of the above components is 100%.

[0013] The roughness of the casting and rolling roller is 0.8-1.2 μm; the roughness of the first cold rolling roller is 0.65-0.75 μm; the roughness of the second cold rolling roller is 0.3-0.6 μm; and the roughness of the third cold rolling roller is 0.15-0.25 μm.

[0014] The casting and rolling process includes four rolling passes, the rolling force of the first pass is 400-600 KN, the rolling force of the second pass is 700-900 KN; the rolling force of the third pass is 800-1000 KN, and the rolling force of the fourth pass is 1000-1200 KN; the rolling speed of the casting and rolling process is 500-700 m / min.

[0015] In the first cold rolling process, the rolling force is 1000-1200 KN, and the rolling speed is 600-800 m / min.

[0016] In the second cold rolling process, the rolling force is 1200-1300 KN, and the rolling speed is 600-800 m / min.

[0017] In the third cold rolling process, the rolling force is 1200-1600 KN, and the rolling speed is 600-800 m / min.

[0018] The present application has outstanding substantial features and significant progress compared with the prior art, specifically, the present application provides a production method of an aluminum foil substrate for copper plating of a PCB copper-aluminum composite foil, the aluminum foil substrate produced by the method has good surface quality and few pinholes, and is suitable for producing the PCB copper-aluminum composite foil. Specifically, by optimizing the annealing process and the cold rolling process, the intermetallics are uniformly dispersed, the impurities in the aluminum foil are precipitated, the number of pinholes on the surface of the aluminum foil is reduced, and the aluminum foil substrate with good surface is obtained. DETAILED DESCRIPTION

[0019] The technical solutions of the present application are described in further detail below through specific embodiments.

[0020] Example 1

[0021] A production method of an aluminum foil substrate for copper plating of a PCB copper-aluminum composite foil, comprising the following steps:

[0022] (1) sequentially performing a melting and casting-rolling process on an aluminum alloy to obtain a blank with a thickness of 7 mm; the casting-rolling process includes four rolling passes, the rolling force of the first pass is 400 KN, the rolling force of the second pass is 700 KN, the rolling force of the third pass is 800 KN, and the rolling force of the fourth pass is 1000 KN; the rolling speed of the casting-rolling process is 500 m / min; the roughness of the casting-rolling roller is 0.8 μm. The aluminum alloy composition is: Si: 0.04-0.25%, Fe: 0.25-0.45%, Cu: 0.01-0.05%, Mn: 0-0.01%, Mg: 0.005-0.02%, Zn: 0-0.01%, Ti: 0.001-0.03%, and the balance is aluminum; the sum of the above components is 100%.

[0023] (2) after the blank is cold-rolled to 3 mm, an annealing process is performed; the roughness of the cold-rolling roller is 0.65 μm, the rolling force is 1000 KN, and the rolling speed is 600 m / min; in the annealing process, first, the temperature is raised to 100-120 °C and kept for 6 h, then the temperature is raised to 500-600 °C within 30 min, and then kept for 2 h;

[0024] (3) after continuously cold-rolling to a thickness of 0.5 mm, an annealing process is performed; the roughness of the cold-rolling roller is 0.6 μm, the rolling force is 1200 KN, and the rolling speed is 600 m / min; in the annealing process, first, the temperature is raised to 320-400 °C, and then kept for 3 h;

[0025] (4) continuously cold-rolling to a thickness of 0.02 mm, the roughness of the cold-rolling roller is 0.15 μm, the rolling force is 1600 KN, and the rolling speed is 800 m / min, then performing a straightening and cutting process to obtain an aluminum foil substrate. The number of A-level pinholes on the surface of the aluminum foil substrate is 42 per 100 m 2 ; the number of A-level pinholes on the surface of the aluminum foil substrate is 23 per 100 m 2 .

[0026] Example 2

[0027] A production method of an aluminum foil substrate for PCB copper-aluminum composite foil copper plating, comprising the following steps:

[0028] (1) sequentially performing melting and cast-rolling processes on an aluminum alloy to obtain a blank with a thickness of 6 mm; the cast-rolling process includes four rolling passes, the rolling force of the first pass is 500 KN, the rolling force of the second pass is 700 KN, the rolling force of the third pass is 1000 KN, and the rolling force of the fourth pass is 1200 KN; the rolling speed of the cast-rolling process is 700 m / min; the roughness of the cast-rolling roller is 1.2 μm. The aluminum alloy comprises: Si: 0.04-0.25%, Fe: 0.25-0.45%, Cu: 0.01-0.05%, Mn: 0-0.01%, Mg: 0.005-0.02%, Zn: 0-0.01%, Ti: 0.001-0.03%, and the balance is aluminum; the sum of the above components is 100%.

[0029] (2) after the blank is cold-rolled to 4 mm, performing an annealing process; the roughness of the cold-rolling roller is 0.65 μm, the rolling force is 1200 KN, and the rolling speed is 600 m / min; in the annealing process, first, the temperature is raised to 100-120℃, and then the temperature is raised to 500-600℃ within 60 min, and then the temperature is kept for 6 h;

[0030] (3) after continuously cold-rolling to a thickness of 1 mm, performing an annealing process; the roughness of the cold-rolling roller is 0.6 μm, the rolling force is 1200 KN, and the rolling speed is 600 m / min; in the annealing process, first, the temperature is raised to 320-400℃, and then the temperature is kept for 5 h;

[0031] (4) continuously cold-rolling to a thickness of 0.4 mm, the roughness of the cold-rolling roller is 0.25 μm, the rolling force is 1200 KN, and the rolling speed is 600 m / min, then performing a straightening and cutting process to obtain an aluminum foil substrate. The number of A-level pinholes on the surface of the aluminum foil substrate is 49 per 100 m 2 ; the number of A-level pinholes on the surface of the aluminum foil substrate is 27 per 100 m 2 .

[0032] Example 3

[0033] A production method of an aluminum foil substrate for PCB copper-aluminum composite foil copper plating, comprising the following steps:

[0034] (1) sequentially performing melting and cast-rolling processes on an aluminum alloy to obtain a blank with a thickness of 6.5 mm; the cast-rolling process includes four rolling passes, the rolling force of the first pass is 400 KN, the rolling force of the second pass is 900 KN, the rolling force of the third pass is 900 KN, and the rolling force of the fourth pass is 1200 KN; the rolling speed of the cast-rolling process is 700 m / min; the roughness of the cast-rolling roller is 1.2 μm. The aluminum alloy composition is as follows: Si: 0.04-0.25%, Fe: 0.25-0.45%, Cu: 0.01-0.05%, Mn: 0-0.01%, Mg: 0.005-0.02%, Zn: 0-0.01%, Ti: 0.001-0.03%, and the balance is aluminum; the sum of the above components is 100%.

[0035] (2) after the blank is cold-rolled to 3 mm, an annealing process is performed; the roughness of the cold-rolling roller is 0.70 μm, the rolling force is 1200 KN, and the rolling speed is 600 m / min; in the annealing process, the temperature is first raised to 100-120℃, and then kept for 8 h, and then the temperature is raised to 500-600℃ within 30 min, and then kept for 4 h;

[0036] (3) after continuously cold-rolling to a thickness of 0.5 mm, an annealing process is performed; the roughness of the cold-rolling roller is 0.4 μm, the rolling force is 1200 KN, and the rolling speed is 600 m / min; in the annealing process, the temperature is first raised to 320-400℃, and then kept for 4 h;

[0037] (4) continuously cold-rolling to a thickness of 0.05 mm, the roughness of the cold-rolling roller is 0.15 μm, the rolling force is 1300 KN, and the rolling speed is 800 m / min, then performing a straightening and cutting process to obtain an aluminum foil substrate. The number of A-level pinholes on the surface of the aluminum foil substrate is 38 per 100 m 2 ; the number of A-level pinholes on the surface of the aluminum foil substrate is 16 per 100 m 2 .

[0038] Example 4

[0039] A production method of an aluminum foil substrate for PCB copper-aluminum composite foil copper plating, comprising the following steps:

[0040] (1) sequentially performing melting and casting-rolling processes on an aluminum alloy to obtain a blank with a thickness of 6 mm; the casting-rolling process includes four rolling passes, the rolling force of the first pass is 400 KN, the rolling force of the second pass is 800 KN, the rolling force of the third pass is 900 KN, and the rolling force of the fourth pass is 1200 KN; the rolling speed of the casting-rolling process is 500 m / min; the roughness of the casting-rolling roller is 0.8 μm. The aluminum alloy components are as follows: Si: 0.04-0.25%, Fe: 0.25-0.45%, Cu: 0.01-0.05%, Mn: 0-0.01%, Mg: 0.005-0.02%, Zn: 0-0.01%, Ti: 0.001-0.03%, and the balance is aluminum; the sum of the above components is 100%.

[0041] (2) performing an annealing process after cold-rolling the blank to 3 mm; the roughness of the cold-rolling roller is 0.65 μm, the rolling force is 1200 KN, and the rolling speed is 600 m / min; in the annealing process, first, the temperature is raised to 100-120℃, and then the temperature is raised to 500-600℃ within 50 min, and then the temperature is kept for 5 h;

[0042] (3) performing an annealing process after continuously cold-rolling to a thickness of 0.7 mm; the roughness of the cold-rolling roller is 0.4 μm, the rolling force is 1200 KN, and the rolling speed is 700 m / min; in the annealing process, first, the temperature is raised to 320-400℃, and then the temperature is kept for 5 h;

[0043] (4) continuously cold-rolling to a thickness of 0.02-0.4 mm, the roughness of the cold-rolling roller is 0.15-0.25 μm, the rolling force is 1200-1600 KN, and the rolling speed is 600-800 m / min, then performing a straightening and cutting process to obtain an aluminum foil substrate. The number of A-level pinholes on the surface of the aluminum foil substrate is 35 per 100 m 2 ; the number of A-level pinholes on the surface of the aluminum foil substrate is 14 per 100 m 2 .

[0044] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and not to limit them; although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the specific embodiments of the present application can be modified or some technical features can be replaced by equivalents; without departing from the spirit of the technical solutions of the present application, they should be covered in the technical solution range of the present application.

Claims

1. A method for producing an aluminum foil substrate for copper plating of a PCB copper-aluminum composite foil, comprising the following steps: (1) sequentially subjecting an aluminum alloy to a melting and casting rolling process to obtain a blank having a thickness of 6-7 mm; (2) cold-rolling the blank to a thickness of 3-4 mm and then performing an annealing process; in the annealing process, the temperature is first raised to 100-120℃ and maintained for 6-12 h, then raised to 500-600℃ within 30-60 min, and then maintained for 2-6 h; (3) continuing to cold-roll to a thickness of 0.5-1 mm and then performing an annealing process; in the annealing process, the temperature is first raised to 320-400℃, and then maintained for 3-5 h; (4) continuing to cold-roll to a thickness of 0.02-0.4 mm, and then performing a straightening and slitting process to obtain the aluminum foil substrate; the aluminum alloy comprises the following components: Si: 0.04-0.25%, Fe: 0.25-0.45%, Cu: 0.01-0.05%, Mn: 0-0.01%, Mg: 0.005-0.02%, Zn: 0-0.01%, Ti: 0.001-0.03%, and the balance being aluminum; the sum of the above components is 100%; the roughness of the casting roll is 0.8-1.2 μm; the roughness of the first cold-rolling roll is 0.65-0.75 μm; the roughness of the second cold-rolling roll is 0.3-0.6 μm; and the roughness of the third cold-rolling roll is 0.15-0.25 μm; the casting process includes four rolling passes; the rolling force of the first pass is 400-600 KN, the rolling force of the second pass is 700-900 KN, the rolling force of the third pass is 800-1000 KN, and the rolling force of the fourth pass is 1000-1200 KN; and the rolling speed of the casting process is 500-700 m / min.

2. The production method of the aluminum foil substrate for copper plating of a PCB copper-aluminum composite foil according to claim 1, characterized by: in the first cold-rolling process, the rolling force is 1000-1200 KN, and the rolling speed is 600-800 m / min.

3. The production method of the aluminum foil substrate for copper plating of a PCB copper-aluminum composite foil according to claim 2, characterized by: in the second cold-rolling process, the rolling force is 1200-1300 KN, and the rolling speed is 600-800 m / min.

4. The production method of the aluminum foil substrate for copper plating of a PCB copper-aluminum composite foil according to claim 3, characterized by: in the third cold-rolling process, the rolling force is 1200-1600 KN, and the rolling speed is 600-800 m / min.