KR20180072494A

KR20180072494A - Apparatus for preparing fe-ni alloy foil

Info

Publication number: KR20180072494A
Application number: KR1020160176116A
Authority: KR
Inventors: 양홍석; 김홍준; 정관호; 이상호; 김현태; 김종권; 김기수
Original assignee: 주식회사 포스코
Priority date: 2016-12-21
Filing date: 2016-12-21
Publication date: 2018-06-29
Also published as: KR101879080B1; WO2018117590A1

Abstract

The present invention relates to an electrolytic bath containing an electrolytic solution; A drum type negative electrode partially immersed in the electrolytic bath and rotated; A cathode immersed in the electrolytic cell and arranged along a periphery of the cathode, the plurality of electrodes being spaced apart from each other; And a liquid supply part immersed in the electrolytic bath and disposed between the positive electrodes to supply an electrolytic solution, wherein a gap between the positive electrode and the negative electrode is relatively wide at the introduction part side with respect to a traveling direction of the electrolytic solution, Nickel alloy foil manufacturing apparatus in which the spacing of the iron-nickel alloy foil is relatively narrow.
According to the present invention, there is provided an apparatus for manufacturing an iron-nickel alloy foil capable of reducing a component deviation in a thickness direction of an iron-nickel alloy foil produced by electroforming.

Description

TECHNICAL FIELD [0001] The present invention relates to an iron-nickel alloy foil manufacturing apparatus,

The present invention relates to an apparatus for producing an alloy foil that reduces the component deviation in the thickness direction which occurs when an alloy foil is produced through electroforming.

Plating is done for various purposes. Many plating systems such as copper, nickel, gold, silver, tin, chrome, lead, and zinc have been developed and used until now depending on the purpose and cost of the plating system and method.

Iron and its alloys are also one of the most studied alloys. There are two major researches on iron plating. One is the relatively low cost alternative to nickel and chromium, and the other is the development of products with specific properties through alloy plating with other elements. Fe-Ni, Fe-Zn, Fe-Cr-Ni, Fe-P, Fe-B, Fe-C and Fe-C-B.

Iron-nickel alloys are one of the areas where many researches have been conducted recently. Iron-nickel-based alloys are used in many fields with excellent physical properties despite their high cost. Among them, permalloy of Fe-80Ni (wt%) has excellent magnetic properties and Fe-36Ni (wt%) Invar alloy has very low coefficient of thermal expansion.

Invar alloy has been widely used in precision machinery and semiconductor materials since Guillaume was found in 1897 and received the Nobel Prize in 1920. In addition, the invar alloy has been linked to the development of various alloys by changing the content of nickel and adding a third alloy element such as cobalt, and the application range of the alloy is being widened.

There are various methods of manufacturing iron-nickel alloys applicable to various fields as described above, but the main method currently used is conventional cold rolling. When the cold rolling method is used, complicated processes such as melting, forging, hot rolling, heat treatment, cold rolling and heat treatment of alloys must be performed. Rolling is a process requiring large scale equipment and consuming a great amount of energy.

In addition, when producing a thin film material, it is necessary to repeat the process of rolling and heat treatment. As the thickness becomes thinner, the process becomes complicated and the production cost rises exponentially. Falls.

In order to overcome the limitations of the conventional manufacturing method, there have been a lot of studies on the production of iron-nickel alloy thin films by electroforming (electroforming) and there are two methods of producing iron- .

One is a batch method in which the iron-nickel alloy is plated, the substrate is taken out, the foil is peeled off, and the plating is carried out again in the electrolytic solution. This method is advantageous for producing a small quantity of various products, but the productivity is very low, and there is a problem that a deviation is caused largely due to a difference in flow by position in the width and the longitudinal direction.

The other is a continuous production system in which the negative electrode of drum or belt type is continuously rotated while electrodeposition and peeling are continued. This method is more productive than the batch method. In addition, even if there is a difference in flow and the like depending on the position in the longitudinal direction, since the plating proceeds and the plating proceeds through all of the longitudinal direction, the positional deviation is smaller than the arrangement method.

The foil produced by the continuous production method has a smaller variation in width and length in comparison with the batch type, but not in the case of quality variation such as composition in the thickness direction. In the case of the arrangement method, since the foil at one position is in the same position and the metal ion is electrodeposited, the change of the electrolyte with the progress of the electrodeposition is small.

On the other hand, in the case of the continuous production method, electric current is supplied while supplying the electrolytic solution through the liquid supply nozzle through a gap surrounded by a pair of circular arc-shaped cathodes facing a rotating cylindrical negative electrode drum installed in the electrolytic cell, Nickel-iron alloy is electrodeposited on the copper foil, and the foil is rolled to produce a metal foil. At this time, the electrolytic solution is supplied to the drum surface toward the center of the drum between the pair of circular arc-shaped positive electrodes.

Therefore, the metal surface of the metal foil, which is electrodeposited on the drum surface, that is, the lowermost end of the drum, between the pair of the two positive electrodes, in which the electrolytic solution is supplied, forms the center of thickness of the metal foil.

The area where the drum is initially immersed in the electrolyte is an area where the shiny side of the foil is electrodeposited. The electrolytic solution of the drum is an electrolytic solution in which metal ions and additives are consumed after the first electrodeposition reaction. The portion of the drum that exits the electrolyte corresponds to the region where the matte side of the foil is electrodeposited, and the electrolyte here is the electrolytic solution which has undergone the electrodeposition reaction after the initial supply.

For this reason, the foil continuously produced through the electroforming process exhibits a compositional deviation that is symmetrical in the thickness direction. Figures 1 and 2 show the composition profiles in the thickness direction of the foil produced by the conventional batch method and continuous production method, respectively. As shown in FIGS. 1 and 2, it can be seen that the foil produced by the continuous production method has a composition difference of about 10 Ni wt% at the center portion in the thickness direction and the surface.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems and it is an object of the present invention to reduce a compositional deviation in a thickness direction occurring in a foil when an alloy is produced by an electroforming method using a drum-shaped negative electrode.

According to an embodiment of the present invention, there is provided an electrolytic cell comprising: an electrolytic bath containing an electrolytic solution; A drum type negative electrode partially immersed in the electrolytic bath and rotated; A cathode immersed in the electrolytic cell and arranged along a periphery of the cathode, the plurality of electrodes being spaced apart from each other; And a liquid supply part immersed in the electrolytic bath and disposed between the positive electrodes to supply an electrolytic solution, wherein a gap between the positive electrode and the negative electrode is relatively wide at the introduction part side with respect to a traveling direction of the electrolytic solution, Nickel alloy foil manufacturing apparatus in which the spacing of the iron-nickel alloy foil is relatively narrow.

The anode may be divided into a plurality of portions.

The size of the divided electrodes may be different for each electrode.

The divided electrodes may be supplied with a different current for each electrode.

And current measuring means for measuring a current flowing between the cathode and the anode.

According to an embodiment of the present invention, component variations in the thickness direction of the alloy foil produced by electroforming can be reduced.

Figure 1 shows the thickness profile profile of an iron-nickel alloy foil produced in a batch mode.
Figure 2 shows the thickness profile profile of an iron-nickel alloy foil produced in a continuous production process.
3 is a schematic view of an electroforming apparatus including a conventional drum-shaped negative electrode
FIG. 4 shows a part of an apparatus for manufacturing an iron-nickel alloy foil in which the distance between the cathode and the anode is different.
FIG. 5 shows changes in the foil component according to the current density applied in the production of the iron-nickel alloy foil.
6 is a graph showing the thickness profile profile of the iron-nickel alloy foil divided into 12 sections.
FIG. 7 shows a comparison between before and after adjusting the interval between the cathode and the anode.
8 is a graph showing the thickness profile of the iron-nickel alloy foil produced by adjusting the distance between the cathode and the anode.

Hereinafter, preferred embodiments of the present invention will be described with reference to various embodiments. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below.

3 is a schematic view of a generally used electroforming system. Referring to Fig. 3, the iron-nickel alloy foil 1 through electroforming or electroforming can be manufactured as follows.

The electrolytic solution is supplied through the liquid-permeable portion 14 into the gap surrounded by the rotating drum-shaped negative electrode 12 provided in the electrolytic bath 11 and the pair of arc-shaped insoluble anodes 13 opposed thereto. At this time, an iron-nickel alloy foil (1) is produced by electrodepositing an iron-nickel alloy on the surface of the negative electrode drum by energizing the current and winding it.

There are various reasons why the compositional deviation in the thickness direction of the iron-nickel alloy foil 1 produced by the electroforming method as described above occurs. 3, the electrolytic solution is supplied from the lowermost end of the drum 12, and the supplied electrolytic solution is supplied to the electrolytic bath through the channel between the surface of the drum 12 and the anode 13 And then discharged. In this process, the electrodeposition of the metal starts from the left drum surface (position 16-1) in Fig. 3, and the electrodeposition of the metal at the opposite side of the drum surface (position 16-2) is terminated.

Therefore, the electrodeposition of the metal to be electrodeposited on the surface of the drum is performed at the portion where the electrodeposition starts and the portion where the electrodeposition is finished, and the center portion in the thickness direction of the metal foil at the lowermost end portion (15) And electrodeposited.

Therefore, the horizontal portion of the drum (the region where the new electrolyte is supplied) where the center portion in the thickness direction of the metal foil is electrodeposited and the region where the both surfaces are electrodeposited as shown in (3) Temperature difference, metal ion concentration difference, pH difference, and additive concentration difference cause a compositional deviation in the thickness direction.

Although it is possible to measure the difference of all these process conditions and trace the cause and make them identical, considering that the metal ion concentration, pH, temperature, etc. can only change as the reaction progresses, .

Another approach is to determine how and where deviations occur after performing the actual process and then compensate for these deviations through variations in other process conditions.

The electrodeposit rate is the concentration of each metal ion that has the greatest effect on the electrodeposition rate when electroplating through plating or electroforming, but other process parameters such as current density, temperature, pH, agitation, additives, etc. also affect the composition .

Accordingly, the present invention provides an apparatus and method for removing a deviation by applying different current densities to different positions.

In a plating system, the voltage drop occurs in several parts but the largest part is the electrical resistance in the plating solution. Since this resistance is proportional to the gap, the current density per position is inversely proportional to the gap.

FIG. 4 shows a part of an apparatus for manufacturing an iron-nickel alloy foil in which the distance between the cathode and the anode is differently arranged according to the present invention.

Referring to FIG. 4, in the present invention, the interval between the positive electrode and the negative electrode is relatively wide (d ₂ , d ₃ ) and relatively wide at the introduction side with respect to the direction of the electrolyte solution, (d ₁ , d ₄ ) are arranged relatively narrowly.

The current density per position in the connected circuit is inversely proportional to the distance between the cathode and anode. Therefore, if the gap on the inlet side is greater than the gap on the outlet side with respect to the direction in which the electrolyte flows, the current density on the inlet side of the electrolyte can be made low.

That is, by adjusting the distance between the cathode and the anode, the current density applied to each position described above can be changed. The concrete inter-pole calculation method is as shown in the following equation (1).

(Equation 1)

Considering that the deviation in the thickness direction can be reduced by using the above-described method, and the deviation in the thickness direction always occurs in a similar manner, it is advantageous in terms of cost to be used by disposing the cathode- .

On the other hand, in the present invention, the anode may be divided into a plurality of (hereinafter, referred to as "divided electrodes").

The size of the divided electrodes may be the same or may be different from each other. At this time, the sizes of all the divided electrodes do not have to be different from each other. Thus, it is possible to control the current density by position. The specific current density calculation method is shown in Equation 2 below.

Equation (2)

As described above, when the anode is divided into several parts and each anode is connected in parallel to control the current density, there is an advantage that the applied current can be finely adjusted to reduce the compositional deviation in the thickness direction.

In addition, the present invention may further include current measuring means for measuring a current flowing between the cathode and the anode, and it is also possible to measure the current density and change the current density applied to the divided electrode.

Hereinafter, the present invention will be described more specifically by way of specific examples. The following examples are provided to aid understanding of the present invention, and the scope of the present invention is not limited thereto.

Example

Example 1

5 shows an example in which the composition of the alloy foil is changed according to the applied current density. In the case of the iron-nickel alloy foil, as shown in Fig. 5, the Ni content of the foil is lowered when the current density is lowered.

When the Ni content of the center portion is high like the iron-nickel alloy foil of FIG. 2, if the current density at the center portion in the longitudinal direction of the cathode is lowered, the Ni content in the center portion in the foil thickness direction is lowered and the deviation can be reduced.

Table 1 shows calculation results according to the following formula (1) for a case where the existing pole interval is 15 mm in order to control the pole distance between the cathode and the anode.

section Component, Ni wt% Crystal current density (A / dm ² ) Correction gap (mm) One 36.5 21.3 14.1 2 34.6 22.7 13.2 3 35.3 22.2 13.5 4 36.3 21.5 14.0 5 39.6 19.0 15.8 6 44.0 15.8 19.0 7 43.2 16.4 18.3 8 45.7 14.6 20.6 9 40.0 18.7 16.0 10 35.6 22.0 13.7 11 34.6 22.7 13.2 12 34.1 23.1 13.0 Average 38.3 20.0

The pole intervals before and after adjustment are shown in Fig. The composition profile in the thickness direction after the polar spacing was adjusted in this manner is shown in Fig. It can be seen that the deviation in the thickness direction component exceeding 10 Ni wt% is reduced to 2 Ni wt%.

Example 2

The anode is divided into 12 sections and each circuit is configured to allow different current to be applied to each section.

As shown in FIG. 6, the profile of the composition in the thickness direction can be divided into twelve sections to find out the composition to be electrodeposited for each section. With reference to the data of FIG. 5, current density was adjusted and applied. The equation is shown in Equation 2 below.

Specifically, FIG. 2 shows a case where a current density of 20 A / dm ² is applied. If you calculate the interval 1, you can apply 22.5 A / dm ² according to the calculation of (38.3-36.5) /1.366+20. The overall results are shown in Table 1 above.

Different current densities were applied to each position according to the component variation to compensate for the deviation, so that a more uniform composition profile in the thickness direction was obtained.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be obvious to those of ordinary skill in the art.

11: electrolytic cell
12: cathode
13: anode
14:

Claims

An electrolytic bath containing an electrolytic solution;
A drum type negative electrode partially immersed in the electrolytic bath and rotated;
A cathode immersed in the electrolytic cell and arranged along a periphery of the cathode, the plurality of electrodes being spaced apart from each other; And
And a liquid-supply unit immersed in the electrolytic bath and disposed between the positive electrodes to supply an electrolytic solution,
Wherein an interval between the positive electrode and the negative electrode is relatively wide at an inlet side with respect to a traveling direction of the electrolytic solution and a gap between the positive electrode and the negative electrode at a discharging side is relatively narrow.

The method according to claim 1,
Wherein the anode is divided into a plurality of parts.

3. The method of claim 2,
Wherein each of the divided electrodes has a different electrode size for each of the divided electrodes.

3. The method of claim 2,
Wherein the split electrode is supplied with a different current for each electrode.

The method according to claim 1,
Further comprising current measuring means for measuring a current flowing between the cathode and the anode.