KR20060013211A - A manufacturing method of high-strength cu workpiece using accumulative roll-bonding process - Google Patents

Abstract

The present invention is a high-strength copper sheet material by a repeated overlap-bonding rolling process configured to repeat a plurality of times the process of rolling in a repeated overlap-bonding rolling (ARB) process after surface treatment of two copper plate having the same size and fixed together It relates to a manufacturing method. The present invention, the first step (100) of surface treatment of the copper plate member 120, the second step 200 of fixing the two copper plate member 120 passed through the first step (100) and the The third step 300 of rolling and joining the two copper plate members 120 passed through the second step 200 and the fourth step 400 of cutting the copper plate member 120 passed through the third step 300. The first step 100, the second step 200, the third step 300 and the fourth step 400 are repeated a plurality of times in succession. In addition, the first step 100 is a degreasing process and a wire brushing process. The third step 300 is a 50% reduction ratio of two overlapping copper plate members 120 at room temperature (25). It is characterized in that the bonding by rolling at a temperature between (C) and medium temperature (250 ℃). According to the present invention as described above, there is an advantage that can continuously manufacture a copper material having high conductivity and high strength at the same time.

Repeated Overlap Bonding (ARB), Copper Plate, Continuous, Repeated

Description

A manufacturing method of high-strength Cu workpiece using Accumulative Roll-Bonding process}

1 is a schematic process conceptual view of a repeat overlap welding process according to the present invention.

Figure 2a is an optical microscopic histogram of the oxygen-free copper before repeated overlap welding rolling process according to the present invention.

Figure 2b is an optical microscope histology of phosphorus acid copper before the repeated overlap welding rolling process according to the present invention.

Figure 3a is a transmission electron microscope (TEM) micrograph after carrying out 8 cycles of repeated overlap bonding rolling process with an oxygen-free copper of a preferred embodiment of the present invention.

Figure 3b is a transmission electron microscope (TEM) micrograph after performing eight cycles (Cycle) repeated overlap-bonding rolling process with phosphorus acid copper which is a preferred embodiment of the present invention.

Figure 4a is a graph showing the change of mechanical properties with the increase in the number of cycles (Cycle) to perform a repeated lap joint rolling process in an oxygen-free copper is a preferred embodiment of the present invention.

Figure 4b is a graph showing the change of mechanical properties with the increase in the number of cycles (Cycle) to perform a repeated overlap welding process with copper phosphorus in the preferred embodiment of the present invention.

Figure 5 is a graph showing the electrical conductivity change curve according to the increase in the number of cycles (Cycle) to perform the repeated overlap welding process with oxygen-free copper and phosphorus acid copper which is a preferred embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

100. ..... First Step 120. ..... Copper Plate

200. ..... The Second Step 300. ..... The Third Step

320. ..... Roller 400. ..... Fourth Step

420. ..... cutter

The present invention relates to a rigid plastic working method, and more particularly, by repeating the surface treatment of two copper plate materials having the same size and then fixed by overlapping and rolling in a repeated overlap-bonding rolling (ARB) process, copper The conductivity of the present invention relates to a method for producing a high strength copper sheet material by a repeated overlap welding process to increase the strength with little drop.

Cumulative Roll-Bonding (ARB) method is one of the rigid plastic processing methods to improve the mechanical properties by minimizing the grain size of the metal material to submicron (Submicron).

In general, conventional plastic processing methods such as rolling or extrusion have an inevitable change in the shape (section area) of the target material when the processing amount is increased, and thus there is a limit in accumulating strain energy in the material. Therefore, the existing plastic working methods do not have a great effect on grain refinement and high strength of metal materials.

On the other hand, in case of rolling with 50% reduction ratio, ARB method is applied to the rolling theory that the thickness reduction by 1/2 for the material causes double increase in the length direction. This method was developed with the focus on the concept. By repeatedly joining and rolling, it is theoretically possible to carry out unlimited plastic processing, and it is a very effective method for grain refinement and high strength of sheet material.

Due to these characteristics, the ARB method has been applied to steel and aluminium (Al) materials, which are representative of structural materials.However, from the practical point of view, it is only necessary to achieve high strength in existing applications such as solid solution strengthening and precipitation strengthening. There is no great advantage over the law of strengthening the law.

Therefore, in order to maximize the practical use of the conventional ARB method, it is necessary to achieve a grain refinement and a high strength, and a rolling process capable of continuous production.

An object of the present invention for solving the above problems, the surface of two copper plate material having the same size and then fixed by overlapping and rolling by repeated overlap-bonding rolling (ARB) process, the conductivity of copper hardly drop the strength It is to provide a high-strength copper sheet material manufacturing method by repeated overlap bonding rolling process to increase the.

Another object of the present invention is to provide a method for producing a high-strength copper sheet material by a repeated overlap bonding rolling process to enable continuous production by applying a repeat overlap welding process.

In order to achieve the above object, a method of manufacturing a high-strength copper sheet material by a repeated overlap bonding rolling process according to the present invention includes a first step of surface-treating a copper plate material and overlapping two copper plate materials passed through the first step. A second step of fixing, a third step of rolling and joining the two copper plate members passed through the second step, and a fourth step of cutting the copper plate member passed through the third step, wherein the first step is performed. The step, the second step, the third step and the fourth step are characterized in that they are repeated a plurality of times in succession.

The first step is characterized in that the degreasing process and the wire brushing (Wire brushing).

The third step is characterized in that the two overlapping copper sheet material by rolling at 50% reduction rate of bonding.

And, the rolling of the third step is characterized in that carried out at a temperature between room temperature (25 ℃) and medium temperature (250 ℃).

According to the present invention as described above, there is an advantage that can continuously manufacture a copper material having high conductivity and high strength at the same time.

Hereinafter, with reference to the accompanying drawings, a preferred embodiment of a high-strength copper sheet material manufacturing method by a repeated overlap welding process according to the present invention having the configuration as described above will be described in detail.

1 shows a schematic process conceptual diagram of a repeat overlap welding process according to the present invention. As shown in the drawing, the repeated overlap welding process is largely composed of four steps. That is, the first step 100 of surface treatment of the copper plate member 120, the second step 200 of overlapping and fixing the two copper plate member 120 passed through the first step 100, and the second A third step 300 of rolling the two copper plate members 120 passed through the step 200, and a fourth step 400 of cutting the copper plate members 120 subjected to the third step 300. It is configured to include.

In the first step 100, two copper plate members 120 having the same size (thickness 1 mm, width 30 mm, length 300 mm) prepared in advance are surface treated. The surface treatment may be performed by degreasing both surfaces of the copper sheet 120 with acetone, alcohol, or the like, and then, one surface of the two copper sheets 120 contacting each other, that is, the third step ( The surface joined by rolling in 300 is a wire brushing process.

After the first step 100, a second step 200 of overlapping and fixing the two copper plate members 120 is performed. The second step 200 overlaps the two copper plate members 120 which have passed through the first step 100, and then places them with spot welding or wires so as not to be displaced in the rolling in the third step 300. It is a process of fixing the copper plate 120.

The two copper plate 120 fixed in this way is subjected to a third step 300 to be joined by rolling in a two-stage rolling mill (not shown). The third step 300 is cold-rolled and joined by inserting the two copper plate members 120 overlapped and fixed in the second step 200 to the roller 320 of the two-stage rolling machine. Bonding).

The cold rolling as described above is rolled at a rolling reduction of 50%. This is based on the theory that when rolling at a rolling reduction of 50%, a thickness reduction of half of the material would result in a twofold increase in the longitudinal direction.

The copper plate 120 joined to the one in the third step 300 passes through the fourth step 400. The fourth step 400 is a process of cutting the copper plate 120, which has become one, into two parts in the longitudinal direction by using the cutter 420.

In addition, as described above, the process from the first step 100 to the fourth step 400 is referred to as one cycle, and the copper plate material 120 cut into two parts in the fourth step 400 is again. The process of surface treatment in the first step 100, the process of overlapping and fixing the second step 200, the cold bonding rolling process of the third step 300, and the process of cutting the fourth step 400 are continuously performed. Will be repeated.

On the other hand, Figure 2a and 2b is an optical microscopic picture of the anaerobic copper and phosphorus acid copper before the repeated overlap-bonding rolling process according to the present invention, Figures 3a and 3b is an oxygen-free copper which is a preferred embodiment of the present invention A transmission electron microscope (TEM) micrograph is shown after eight cycles of repeated overlap bonding rolling process with phosphoric acid copper.

4A and 4B are graphs showing a change curve of mechanical properties according to an increase in the number of cycles for carrying out a repeated bond welding process using oxygen-free copper and phosphorus acid copper, which are preferred embodiments of the present invention. 5 is a graph showing a change in electric conductivity with increasing cycle number of cycles of repeated annealing welding with anoxic copper and phosphorus acid copper, which is a preferred embodiment of the present invention.

First, as shown in FIGS. 2A and 2B, the optical microscope micrographs before the repeated overlap-bonding rolling process of two kinds of copper (oxygen-free copper and phosphorus acid) having the following chemical compositions, Representing the recrystallized structure, the mean grain diameter is shown to be 63 μm of anhydrous copper and 45 μm of phosphorus acid.

<Anaerobic Copper>

Cu O Pb Bi Fe P S 99.99 2 ppm 1 ppm <1 ppm 1 ppm 2 ppm 7 ppm

<Intalsandong>

Cu Sn Pb Bi Fe P Mn 99.9 0.002 0.017 <1 ppm 1 ppm 0.02 0.001

3A and 3B are transmission electron microscope (TEM) micrographs showing ultrafine grains formed in anoxic copper and phosphorus acid copper after 8 cycles of repeated overlap welding. FIG. 3A is a dark field image. ), An ultrafine grain having a diameter of about 500 nm is formed in the anaerobic copper tissue, and FIG. 3B is a bright field image. It can be seen that grains are formed.

These results show that the ARB method is effective for ultrafine grains of copper (Cu).

4A and 4B show changes in the mechanical properties of anoxic copper and phosphorus acid copper with an increase in the amount of significant strain (ARB cycles). In the case of anoxic copper (FIG. 4A), the tensile strength (UTS) increases as the number of cycles up to 4 cycles. Therefore, it continues to increase, reaching 390 MPa, which is 2.1 times of the initial time, but it does not change much even if the number of cycles increases more than five cycles, and elongation decreases significantly in one cycle, but increases slightly as the number of cycles increases.

Meanwhile, in the case of phosphorus copper (FIG. 4B), as the number of cycles increases, the tensile strength continues to increase to about 3 times after 7 cycles, reaching 550 MPa, and the change in elongation is similar to that of anoxic copper. As mentioned above, although there is a large or small amount of reinforcing effect due to ARB, both anoxic copper and phosphorus acid copper are greatly strengthened by ARB.

5 shows the change in the electrical conductivity of anoxic copper and phosphorus acid copper according to ARB, and the reduction amount is insignificant even if the number of ARB cycles is increased in both anoxic copper and phosphorus acid copper. It can be seen.

The scope of the present invention is not limited to the above-exemplified embodiments, and many other modifications based on the present invention may be made by those skilled in the art within the above technical scope.

As described in detail above, in the method of manufacturing a high-strength copper sheet material by the repeated overlap bonding rolling process of the present invention, two copper sheet materials having the same size are surface-treated, and then fixed by overlapping to roll in the repeated overlap bonding rolling (ARB) process. The process was configured to repeat multiple times in succession.

Accordingly, an effect of continuously producing a copper (Cu) material having both high electroconductivity and high strength by using an ARB process is expected.

Further, the copper (Cu) material produced by the present invention as a base material is also expected to be effective in the electrical / electronic industrial materials such as semiconductors, communication devices and applications thereof.

Claims (4)

A first step of surface treating the copper sheet material, A second step of overlapping and fixing two copper plate members which have been subjected to the first step, A third step of rolling and joining the two copper plate members passed through the second step, It comprises a fourth step of cutting the copper plate material subjected to the third step, The first step, the second step, the third step and the fourth step is a high-strength copper sheet material manufacturing method by a repeated overlap bonding rolling process, characterized in that repeated multiple times in succession. The method of claim 1, wherein the first step is a degreasing process and a wire brushing process. The method of claim 1, wherein the third step is performed by joining two overlapping copper sheets by rolling at a reduction ratio of 50%. The method of claim 1, wherein the rolling of the third step is performed at a temperature between room temperature (25 ° C.) and medium temperature (250 ° C.).

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