JP4970742B2 - Aluminum material for electrolytic capacitor electrode, method for producing aluminum material for electrolytic capacitor, anode material for aluminum electrolytic capacitor, and aluminum electrolytic capacitor - Google Patents

Description

  The present invention relates to an aluminum material for an electrolytic capacitor electrode having a high capacitance and excellent bending strength, a method for producing an aluminum material for an electrolytic capacitor, an anode material for an aluminum electrolytic capacitor, and an aluminum electrolytic capacitor.

  In this specification, the term “aluminum” is used to include both aluminum and its alloys, and the aluminum material includes at least an aluminum foil, an aluminum plate, and a molded body thereof.

  An aluminum foil generally used as an electrode material for an aluminum electrolytic capacitor is usually subjected to an electrochemical or chemical etching treatment in order to increase the capacitance per unit area by expanding its effective area. However, in recent years, there has been an increasing need for higher capacitance due to the demand for downsizing of parts due to product downsizing.

  However, sufficient electrostatic capacity cannot be obtained simply by etching the foil. For this reason, in general, in the final annealing step after foil rolling, high temperature heat treatment exceeding 500 ° C. is performed to improve the occupation ratio of {100} <001> orientation (hereinafter referred to as cube orientation) (non- Patent Document 1) and an example of adding Cu as a trace element (Non-Patent Document 2) have been proposed. The improvement of the cube orientation tends to cause an extreme decrease in the elongation in the rolling direction and the bending strength tends to decrease.

  In addition, as the need for high capacity increases, the etching layer tends to become thicker. However, if the length of the etch pit is increased, it becomes difficult to control the length of each etch pit. This also makes it difficult to ensure the bending strength.

  Therefore, there is a demand for an aluminum material for electrolytic capacitor electrodes that is excellent in etching characteristics and can realize a high capacitance and also has excellent bending strength.

  In response to this requirement, a method has been proposed in which the foil has a multi-layer structure to ensure the bending strength. For example, in Patent Document 1, the core layer is made of aluminum containing more Fe than the outer layer, and the growth of etch pits that grow from the surface during etching is caused by Al-Fe intermetallic compounds contained in the core layer. The method of securing the strength by stopping and reliably leaving the core layer, and in Patent Document 2, tries to obtain the same effect as described above by using an aluminum alloy whose purity is lower than that of the outer layer. A method is described.

  On the other hand, Patent Document 3 describes a method of securing the thickness of the core by stopping the growth of etch pits by making the core layer an aluminum layer having a non- (100) orientation of 40% or more.

Patent Document 4 proposes a method of ensuring strength by containing Sc in the core material, and Patent Document 5 proposes a method of securing strength by containing Sc and Zr in the core layer.
Kenshiro Yamaguchi: Light Metal, 35 (1985), P365 N. Kawashima, Y. Nakamura, Moto Nishizaka: Light Metal, No. 21 (1956), P. 54 Japanese Patent Laid-Open No. 51-113154 JP 62-47110 A Japanese Patent Laid-Open No. 4-120235 JP 2000-91164 A JP 2000-345271 A

  However, the methods described in Patent Document 1 and Patent Document 2 have a problem in that a coarse intermetallic compound present in the core material becomes a defect in the chemical conversion film, and leakage current is remarkably increased.

  Further, although the method of Patent Document 3 can suppress the growth of etch pits to some extent, the growth cannot be completely stopped, the core remaining part becomes non-uniform, and the material strength of the core layer is almost equal to that of the outer layer. However, there is a problem that sufficient folding strength as a laminated material cannot be ensured.

  Further, in the methods described in Patent Document 4 and Patent Document 5, although the effect of improving the strength of the core layer is recognized, the boundary between the core layer material and the outer layer material becomes unclear due to impurity diffusion. It was not always sufficient to stop the growth and suppress the strength reduction of the core layer.

  The present invention has been made in view of such a technical background, and is an electrolytic capacitor excellent in etching characteristics and excellent in bending resistance as well as having excellent etching characteristics without increasing leakage current. An object of the present invention is to provide an aluminum material for an electrode, and further to provide a method for producing the aluminum material, an anode material for an aluminum electrolytic capacitor, and an aluminum electrolytic capacitor.

The object is achieved by the following means.
(1) An outer layer is laminated on at least one side of a core layer occupying 5% or more and 40% or less of the total thickness, and the core layer has an aluminum purity of 99.3% by mass or more, and Si; .0005 mass% or more and 0.03 mass% or less, Fe; 0.0005 mass% or more and 0.03 mass% or less, Cu; 0.0005 mass% or more and 0.015 mass% or less, Mn; 0.00003 mass% or more 0.001% by mass or less, Mg: 0.00003% by mass or more and 0.005% by mass or less, Zn: 0.00003% by mass or more and 0.005% by mass or less, Ti: 0.00003% by mass or more and 0.001% by mass Hereafter, Cr: 0.00003 mass% or more and 0.003 mass% or less, Ni: 0.00003 mass% or more and 0.003% or less, Ga: 0.00003 mass% or more and 0.008 mass% or less, B; 0 00003 mass% to 0.002 mass%, V; 0.00003 mass% to 0.05 mass%, Sc; 0.005 mass% to 0.1 mass%, Zr; 0.005 mass% to 0 The area occupancy of the crystal structure having a crystal orientation component with a deviation angle of 10 degrees or less among the crystal orientation components seen from the material surface is 0.02 ≦ [S _Cube + S _Goss ] / [S _Brass + S _C + S _S ] ≦ 0.35 (where S _Cube is the cubic orientation {100} <001>, S _Goss is the Goss orientation {110} <001>, and S _Brass is the Brass orientation {110} <112>, S _C are C orientation {112} <111>, S _S is each orientation component of S orientation {123} <634>, and the outer layer has an aluminum purity of 99.6% by mass. The cubic orientation {100} <0 as seen from the material surface as described above An aluminum material for electrolytic capacitor electrodes, wherein the area occupancy S _Cube of a crystal structure having a crystal orientation component whose deviation angle from 01> is 10 degrees or less is 80% or more.
(2) The outer layer is composed of Si; 0.0005 mass% to 0.03 mass%, Fe; 0.0005 mass% to 0.03 mass%, Cu; 0.0005 mass% to 0.015 mass% Hereafter, Mn: 0.00003 mass% or more and 0.001 mass% or less, Mg: 0.00003 mass% or more and 0.005 mass% or less, Zn: 0.00003 mass% or more and 0.005 mass% or less, Ti; 0 0.0003% by mass or more and 0.001% by mass or less, Cr: 0.00003% by mass or more and 0.003% by mass or less, Ni: 0.00003% by mass or more and 0.003% by mass or less, Ga: 0.00003% by mass or more 0.005 mass% or less, B; 0.00003 mass% or more and 0.002 mass% or less, V; 0.00003 mass% or more and 0.003 mass% or less, Sc; 0.00003 mass% or more and 0.00 Mass% or less, Zr; electrolytic capacitor electrodes for aluminum material according to item 1 containing 0.003% by mass or less 0.00003 mass% or more.
(3) The core layer is Y: 0.00003 mass% or more and 0.03 mass% or less, La: 0.00003 mass% or more and 0.03 mass% or less, Ce; 0.00003 mass% or more and 0.03 mass% 2. The aluminum material for electrolytic capacitor electrodes as recited in the aforementioned Item 1, further containing at least one type of at least 1%.
(4) The outer layer is Pb; 0.00003 mass% or more and 0.0003 mass% or less, Sn; 0.0003 mass% or more and 0.003 mass% or less, Bi; 0.00001 mass% or more and 0.00015 mass% or less. 3. The aluminum material for electrolytic capacitor electrodes as described in 2 above, which contains at least one kind of Sb: 0.0002 mass% or more and 0.002 mass% or less.
(5) The sum Ccore (Sc + Zr + V) of the Sc and Zr, V concentrations of the core layer and the sum Cskin (Sc + Zr + V) of the Sc, Zr, and V concentrations of the outer layer subjected to etching 5. The aluminum material for electrolytic capacitor electrodes according to any one of 1 to 4 above, wherein 5 ≦ Ccore (Sc + Zr + V) / Cskin (Sc + Zr + V) ≦ 500.
(6) The aluminum material for electrolytic capacitor electrodes as described in any one of 1 to 5 above, wherein an interval between average grain boundaries in the thickness direction of the core layer is 20 μm or less.
(7) The aluminum material for electrolytic capacitor electrodes as described in any one of 1 to 6 above, wherein the ratio (Hvskin / Hvcore) of the hardness Hvcore of the core layer to the hardness Hvskin of the outer layer is 0.2 or more and 0.8 or less.
(8) The purity of aluminum is 99.3% by mass or more, and Si: 0.0005% by mass to 0.03% by mass, Fe: 0.0005% by mass to 0.03% by mass, Cu: 0 .0005 mass% or more and 0.015 mass% or less, Mn: 0.00003 mass% or more and 0.001 mass% or less, Mg: 0.00003 mass% or more and 0.005 mass% or less, Zn: 0.00003 mass% or more 0.005% by mass or less, Ti: 0.00003% by mass or more and 0.001% by mass or less, Cr: 0.00003% by mass or more and 0.003% by mass or less, Ni: 0.00003% by mass or more and 0.003% by mass Hereafter, Ga: 0.00003 mass% or more and 0.008 mass% or less, B: 0.00003 mass% or more and 0.002 mass% or less, V: 0.00003 mass% or more and 0.05 mass% or less, Sc 0.005% by mass or more and 0.1% by mass or less, Zr: 0.005% by mass or more and 0.2% by mass or less on at least one surface of the core layer, Si; 0.0005% by mass or more and 0.03% by mass or less Fe: 0.0005 mass% or more and 0.03 mass% or less, Cu: 0.0005 mass% or more and 0.015 mass% or less, Mn: 0.00003 mass% or more and 0.001 mass% or less, Mg; 00003 mass% to 0.005 mass%, Zn: 0.00003 mass% to 0.005 mass%, Ti; 0.00003 mass% to 0.001 mass%, Cr; 0.00003 mass% to 0 0.003 mass% or less, Ni: 0.00003 mass% or more and 0.003 mass% or less, Ga: 0.00003 mass% or more and 0.005 mass% or less, B; 0.00003 mass% or more and 0.002 mass% Hereinafter, an outer layer having V: 0.00003% by mass to 0.003% by mass, Sc: 0.00003% by mass to 0.003% by mass, Zr: 0.00003% by mass to 0.003% by mass After the lamination, hot rolling and cold rolling are performed, and then, when performing the final annealing, at least 200 ° C. to 300 ° C., 30 minutes to 6 hours from the hot rolling to the final annealing. A method for producing an aluminum material for electrolytic capacitor electrodes, wherein the intermediate annealing is performed once and the final annealing is performed under a condition of 430 ° C. or higher and lower than 500 ° C. for 30 minutes or longer and 6 hours or shorter.
(9) The core layer is Y: 0.00003% by mass or more and 0.03% by mass or less, La: 0.00003% by mass or more and 0.03% by mass or less, Ce: 0.00003% by mass or more and 0.03% by mass The manufacturing method of the aluminum material for electrolytic capacitor electrodes of the preceding clause 8 which further contains at least 1 type of% or less.
(10) The outer layer is composed of Pb; 0.00003 mass% or more and 0.0003 mass% or less, Sn: 0.0003 mass% or more and 0.003% or less, Bi; 0.00001 mass% or more and 0.00015 mass% or less. 9. The method for producing an aluminum material for electrolytic capacitor electrodes as recited in the aforementioned Item 8, wherein at least one element comprising Sb: 0.0002 mass% or more and 0.002 mass% or less is contained.
(11) In any one of the preceding items 1 to 10, wherein additional strain is applied by cold rolling at a rolling reduction of 8% or more and 30% or less or warm rolling not exceeding the intermediate annealing temperature between the intermediate annealing and the final annealing. The manufacturing method of the aluminum material for electrolytic capacitor electrodes of description.
(12) Before the intermediate annealing and the final annealing, the additional strain is applied by applying the tensile deformation at a cold rate of 5% to 15% or the tensile deformation at a temperature not exceeding the intermediate annealing temperature. 10. The method for producing an aluminum material for electrolytic capacitor electrodes according to 10.
(13) The aluminum electrolysis characterized in that the aluminum material for electrolytic capacitor electrodes according to any one of the preceding items 1 to 7 is etched to have a surface area of 10 times or more of a projected area before etching. Anode material for capacitors.
(14) The anode material for an aluminum electrolytic capacitor as described in (13) above, wherein a dielectric film having an average film thickness of 0.1 μm or more is formed in the etch pit forming portion.
(15) An electrolytic capacitor characterized in that at least 30% or more of etch pits are generated from a starting point provided in advance on the surface of the aluminum material when the aluminum material for electrolytic capacitor electrodes according to items 1 to 7 is subjected to an etching treatment. Manufacturing method of aluminum material for electrodes.
(16) An outer layer is laminated on at least one side of a core layer occupying 5% to 40% of the total thickness, and the core layer has an aluminum purity of 99.3% by mass or more, and Si; .0005 mass% or more and 0.05 mass% or less, Fe; 0.0005 mass% or more and 0.05 mass% or less, Cu; 0.0005 mass% or more and 0.015 mass% or less, Mn: 0.00003 mass% or more 0.001% by mass or less, Mg: 0.00003% by mass or more and 0.005% by mass or less, Zn: 0.00003% by mass or more and 0.005% by mass or less, Ti: 0.00003% by mass or more and 0.001% by mass Hereafter, Cr: 0.00003 mass% or more and 0.003 mass% or less, Ni: 0.00003 mass% or more and 0.003 mass% or less, Ga: 0.00003 mass% or more and 0.008 mass% or less, B; 0.00003 mass% to 0.002 mass%, V; 0.00003 mass% to 0.05 mass%, Sc; 0.005 mass% to 0.1 mass%, Zr; 0.005 mass% or more The outer layer has an aluminum purity of 99.6% by mass or more, Si; 0.0005% by mass to 0.05% by mass, Fe; 0.0005% by mass to 0%. 0.05% by mass or less, Cu: 0.0005% by mass or more and 0.015% by mass or less, Mn: 0.00003% by mass or more and 0.001% by mass or less, Mg: 0.00003% by mass or more and 0.005% by mass or less Zn: 0.00003 mass% or more and 0.005 mass% or less, Ti: 0.00003 mass% or more and 0.001 mass% or less, Cr: 0.00003 mass% or more and 0.003 mass% or less, Ni; 000 3 mass% or more and 0.003 mass% or less, Ga: 0.00003 mass% or more and 0.005 mass% or less, B: 0.00003 mass% or more and 0.002 mass% or less, V; 0.00003 mass% or more 0 0.003 mass% or less, Sc; 0.00003 mass% or more and 0.003 mass% or less, Zr; 0.00003 mass% or more and 0.003 mass% or less, and by AC etching, the surface area is before etching An anode material for an aluminum electrolytic capacitor, wherein the anode material is 50 times or more the projected area.
(17) The anode material for an aluminum electrolytic capacitor as described in 16 above, wherein a dielectric film having an average film thickness of 0.5 μm or less is formed in the etch pit formation portion.
(18) An aluminum electrolytic capacitor, wherein the anode material according to any one of items 13, 14, 16, and 17 is used as an electrode material.

  According to the invention described in the preceding item (1), the outer layer to be etched has an aluminum layer having a high cubic occupancy ratio, the core layer has excellent film characteristics at the time of chemical conversion, a small leakage current, and an etch pit. Since the core layer is a high-strength alloy layer that can suppress the growth of the outer layer, the outer layer can be etched sufficiently while ensuring the bending strength, the overall capacitance is high, and the folding strength is excellent. Thus, an aluminum material for an electrolytic capacitor electrode that does not cause material breakage when wound on a coil or the like can be obtained.

  According to the invention described in the preceding item (2), by limiting the composition of the outer layer, the etching characteristics of the outer layer can be further improved, and a higher capacitance can be realized.

  According to the invention described in the preceding item (3), since it further contains at least one kind of Y, La, and Ce within a predetermined range, the bending strength can be further increased.

  According to the invention described in the preceding item (4), since the outer layer contains at least one kind of Pb, Sn, Bi, and Sb in a predetermined amount, the etching characteristics of the outer layer can be further improved.

  According to the invention described in the preceding item (5), the sum Ccore (Sc + Zr + V) of the concentration of Sc and Zr, V of the core layer and the sum of the concentrations of Sc, Zr, V of the outer layer subjected to etching. Since Cskin (Sc + Zr + V) has a relationship of 5 ≦ Ccore (Sc + Zr + V) / Cskin (Sc + Zr + V) ≦ 500, the tunnel type etch pits progress to the core layer. It can be reliably blocked and can achieve excellent bending strength.

  According to the invention described in item (6) above, since the interval between the average grain boundaries in the thickness direction of the core layer is 20 μm or less, the progress of etch pits to the core layer can be further prevented.

  According to the invention described in the preceding item (7), the ratio of the hardness Hvcore of the core layer to the hardness Hvskin of the outer layer (Hvskin / Hvcore) is 0.2 or more and 0.8 or less. Thus, the difference in dislocation density is caused, thereby improving the etch pit progression prevention effect.

  According to the invention described in the preceding item (8), an aluminum material for electrolytic capacitor electrodes, which has a high electrostatic capacity and excellent folding resistance and does not cause material breakage when wound on a coil or the like, is produced. Can do.

  According to the invention described in the preceding item (9), since it further contains at least one of Y, La, and Ce within a predetermined range, an aluminum material for electrolytic capacitor electrodes that is further excellent in folding strength can be manufactured. .

  According to the invention described in the preceding item (10), since the outer layer contains at least one kind of Pb, Sn, Bi, and Sb, it is possible to manufacture an aluminum material for electrolytic capacitor electrodes that is further excellent in etching characteristics. .

  According to the invention described in the preceding item (11), between the intermediate annealing and the final annealing, additional strain is imparted by cold rolling with a rolling reduction of 8% or more and 30% or less or warm rolling that does not exceed the intermediate annealing temperature. Since it implements, the structure | tissue state of a core layer and an outer layer is controlled, and the structure | tissue state of the core layer and outer layer described in previous clause (1) can be obtained more stably.

  According to the invention described in the preceding item (12), additional strain is imparted by tensile deformation at a cold rate of 5% or more and 15% or less or tensile deformation at a temperature not exceeding the intermediate annealing temperature. The tissue state of the core layer and the outer layer described in the preceding item (1) can be obtained more stably.

  According to the invention described in the preceding item (13), since the surface area is 10 times or more of the projected area before etching by etching, the anode material for an aluminum electrolytic capacitor having a high capacitance can be obtained.

  According to the invention described in the preceding item (14), since the dielectric film having an average film thickness of 0.1 μm or more is formed, it can be formed as an anode material for an aluminum electrolytic capacitor having a withstand voltage required as a capacitor.

  According to the invention described in the preceding item (15), at least 30% or more of the etch pits are generated by the starting points previously provided on the surface of the aluminum material, so that the etch pits can be uniformly dispersed. Thus, combined with the fact that a sufficient pit depth can be secured by the outer layer, it becomes possible to produce an aluminum material for electrolytic capacitor electrodes having an extremely high capacitance.

  According to the invention described in the preceding item (16), it can be made an aluminum material for electrolytic capacitor electrodes, particularly for low pressure, which is excellent in both strength and etching characteristics.

  According to the invention described in the preceding item (17), since the dielectric film having an average film thickness of 0.5 μm or less is formed in the etch pit forming portion, a higher capacitance can be realized.

  According to the invention described in item (18), an aluminum electrolytic capacitor having a high capacitance can be obtained.

  The aluminum material for electrolytic capacitor electrodes according to this embodiment ensures strength and elongation by the crystal grain structure of the core layer and the inherent strain.

  Generally, a high-purity aluminum material used for an electrode material for electrolytic capacitors is exposed to a high-temperature atmosphere of 300 ° C. to 500 ° C. in a drying process or a chemical conversion treatment process after the etching process. At this time, even if the material is a hard foil, softening or recrystallization occurs. In the case of a soft foil, since the Al purity is high, the crystal grain size increases, the number of crystal grains occupying in the plate thickness direction decreases, and the elongation and the bending strength decrease.

  At this time, the aluminum purity is 99.3% by mass or more, Si: 0.0005% by mass to 0.03% by mass, Fe: 0.0005% by mass to 0.03% by mass, Cu; 0.0005 Mass% or more and 0.015 mass% or less, Mn; 0.00003 mass% or more and 0.001 mass% or less, Mg; 0.00003 mass% or more and 0.005 mass% or less, Zn; 005% by mass or less, Ti: 0.00003% by mass or more and 0.001% by mass or less, Cr: 0.00003% by mass or more and 0.003% by mass or less, Ni: 0.00003% by mass or more and 0.003% by mass or less, Ga; 0.00003 mass% to 0.008 mass%, B; 0.00003 mass% to 0.002 mass%, V; 0.00003 mass% to 0.05 mass%, Sc; An aluminum alloy containing a composition of 0.005 mass% or more and 0.1 mass% or less, Zr; 0.005 mass% or more and 0.2 mass% or less has a high recrystallization temperature and is difficult to soften.

  Therefore, by using an aluminum material having this composition as a core layer and laminating an outer layer excellent in etching characteristics on the core layer, an aluminum material excellent in etching characteristics, strength and elongation can be obtained as a whole.

  However, the thickness of the core layer needs to be 5% to 40% of the total thickness of the aluminum material. If the thickness of the core layer is less than 5% of the total thickness of the aluminum material, the overall strength of the aluminum material is lowered because the thickness of the core layer is insufficient. When the thickness of the core layer exceeds 40% of the total thickness of the aluminum material, the outer layer becomes too thin and the length of the etch pit is shortened, so that a high capacitance due to a sufficiently large area cannot be obtained. A preferable thickness of the core layer is 10% or more and 35% or less of the total thickness of the aluminum material.

  The outer layer may be laminated on both sides of the core layer, or may be laminated only on one side.

  For the outer layer, high-purity aluminum having an aluminum purity with excellent etching characteristics of 99.6% or more, preferably 99.9% or more is used. Since the material strength is ensured by the presence of the core layer, the area expansion ratio of the outer layer can be increased by etching, and a high capacitance can be achieved.

  Further, when the surface expansion treatment is performed by forming tunnel type etch pits, it is preferable that the outer layer has a crystal structure having a high occupancy ratio of the cubic orientation on the surface in order to ensure the surface expansion ratio of the aluminum material. This is because if the crystal structure of the outer layer surface is greatly deviated from the cubic orientation, the amount of dissolution of the outer layer surface increases during etching and the length of the etch pit is shortened, resulting in a local decrease in capacitance.

In order to suppress such a local overmelting phenomenon, it is necessary that the area occupancy S _Cube of the crystal structure whose deviation angle from the cube orientation (Tolerance) is 10 degrees or less is 80% or more, In particular, a remarkable effect is obtained when it is 90% or more.

  The outer layer is made of Si; 0.0005 mass% or more and 0.03 mass% or less, Fe; 0.0005 mass% or more and 0.03 mass% or less, Cu; 0.0005 mass% or more and 0.015 mass% or less. , Mn: 0.00003 mass% to 0.001 mass%, Mg: 0.00003 mass% to 0.005 mass%, Zn: 0.00003 mass% to 0.005 mass%, Ti; 00003 mass% or more and 0.001 mass% or less, Cr: 0.00003 mass% or more and 0.003 mass% or less, Ni: 0.00003 mass% or more and 0.003 mass% or less, Ga: 0.00003 mass% or more 0 0.005 mass% or less, B; 0.00003 mass% or more and 0.002 mass% or less, V; 0.00003 mass% or more and 0.003 mass% or less, Sc; 0.00003 mass% or more and 0.00 Mass% or less, Zr; 0.00003 it is composition containing mass% or more 0.003 mass% or less is desirable in that it can further improve the etching characteristics.

  In addition, since at least one of Y, La, and Ce coexists with Zr and Sc in the core layer, recrystallization of aluminum is remarkably suppressed, which is effective in improving the strength of the core layer. Therefore, desirably, the core layer is Y; 0.00003 mass% or more and 0.03 mass% or less, and the optimum range is 0.003 or more and 0.025 mass% or less, La; 0.00003 mass% or more and 0.03 mass%. % By mass or less, the optimum range is 0.002% by mass or more and 0.02% by mass or less, Ce; 0.00003% by mass or more and 0.03% by mass or less, and the optimum range is 0.003% by mass or more and 0.03% by mass or less. It is good to contain at least 1 type of% or less.

  Further, even if the core layer has sufficient strength, if the core layer is thinned or disappears due to the growth of the tunnel-type etch pit described above, the effect cannot be obtained at all.

  As a result of diligent research, we have confirmed that the growth of etch pits can be reliably stopped by controlling a specific crystal orientation among the crystal orientation components seen from the surface of the material in the core layer and combining it with the aforementioned composition. I found it.

That is, S _Cube in the core layer ... Cube orientation {100} <001>
S _Goss ... Goss direction {110} <001>
S _Brass … Brass orientation {110} <112>
S _C ... C orientation {112} <111>
S _S ... S direction {123} <634>)
The area occupying ratio of the crystal structure having each orientation component in the entire core layer is 0.02 ≦ [S _Cube + S _Goss ] / [S _Brass + S _C + S _S ] ≦ 0.35
As described above, it has been found that it is effective that the outer layer occupies 80% or more of the area occupation ratio S _Cube of the crystal structure having the cubic orientation as viewed from the material surface. . In this case, a deviation angle (Tolerance) from each azimuth component is allowed within 10 degrees.

If [S _Cube + S _Goss ] / [S _Brass + S _C + S _S ] exceeds 0.35, the growth of tunnel-type etch pits cannot be effectively stopped. If it is less than 0.02, peeling of the etching layer due to electrochemical dissolution tends to occur at the interface between the outer layer and the core layer during etching. The optimum value of [S _Cube + S _Goss ] / [S _Brass + S _C + S _S ] of the core layer is 0.05 to 0.25.

Further, when the area occupancy S _{Cube in} the cube orientation of the outer layer is less than 80% when tunnel type etching is performed, surface dissolution is likely to occur, and the length of the tunnel type etch pit is shortened, so that the surface expansion ratio is reduced. In addition, since the crystal orientation relationship with the core layer changes, it becomes impossible to effectively stop the growth of the tunnel type etch pits. The optimum value of the area occupancy S _Cube of the crystal structure having a cubic orientation in the outer layer is 90% or more.

  Further, in the outer layer, Pb: 0.00003 mass% or more and 0.0003 mass% or less, in order to make the initial etch pit generation uniform, eliminate the surface dissolution non-uniform region, and make the etch pit length uniform. Sn: 0.0003% by mass or more and 0.003% by mass or less, Bi: 0.00001% by mass or more and 0.00015% by mass or less, Sb: One or more types of 0.0002% by mass or more and 0.002% by mass or less It is desirable to do. Optimum content ranges are Pb; 0.00005 mass% to 0.00015 mass%, Sn: 0.0005 mass% to 0.0020 mass%, Bi; 0.00002 mass% to 0.00005 mass% , Sb: 0.0005 mass% or more and 0.00015 mass% or less.

  In addition, Pb, Sn, Bi, Sb, etc. contained in the outer layer may diffuse into the core layer due to the thermal history during the manufacturing process. It is permissible to contain these elements in the core layer.

In addition, it is effective to control the concentration ratio of Sc, Zr, and V between the core layer and the outer layer as a method for reliably stopping the progress of the tunnel-type etch pit to the core layer and ensuring the strength of the core layer. ,desirable. In this case, when the sum of the concentrations of Sc, Zr, and V in the core layer is Ccore (Sc + Zr + V) and the sum of the concentrations of Sc, Zr, and V in the outer layer is Cskin (Sc + Zr + V),
5 ≦ Ccore (Sc + Zr + V) / Cskin (Sc + Zr + V) ≦ 500
This effect can be expected when the following relationship is established. If Ccore (Sc + Zr + V) / Cskin (Sc + Zr + V) is less than 5, the above effect is poor, and if it exceeds 500, the chemical conversion characteristics at the interface between the core layer and the outer layer may be deteriorated. The optimum range is 50 ≦ Ccore (Sc + Zr + V) / Cskin (Sc + Zr + V) ≦ 380.

  Further, in addition to the above, the effect of stopping the progress of tunnel-type etch pits can be improved by reducing the average grain boundary interval in the thickness direction of the core layer and increasing the crystal grain boundary in the thickness direction. In this case, the crystal grain size (grain interface distance) in the thickness direction is desirably 20 μm or less, and optimally 10 μm or less.

  Further, by providing a difference in the dislocation density between the core layer and the outer layer, the effect of stopping the progress of the etch pit can be further expected. In this case, it is desirable that the ratio (Hvskin / Hvcore) of the hardness Hvcore of the core layer and the hardness Hvskin of the outer layer be 0.2 or more and 0.8 or less. If Hvskin / Hvcore exceeds 0.8, the difference in hardness between the core layer and the outer layer becomes too small, and the progress of etch pits cannot be sufficiently suppressed. On the other hand, if it is less than 0.2, the ductility of the core layer is lowered, and the bending strength is lowered. The optimum value of Hvskin / Hvcore is 0.4 or more and 0.6 or less.

  As a method for obtaining a multilayer structure material having the above-described structure, a conventional method was used in which an aluminum material having a composition corresponding to a core layer that was melt-cast and chamfered and hot-rolled was used as a core material. In the process of hot rolling, the three layers of the material that are made by chamfering the aluminum ingot having the composition corresponding to the outer layer are hot rolled, followed by intermediate annealing at least once in the course of cold rolling, followed by additional rolling and final annealing. The process of performing can be illustrated. In this case, the intermediate annealing is 200 ° C. or more and 300 ° C. or less, 30 minutes or more and 6 hours or less (in the case of two or more intermediate annealings, each is 6 hours or less), and the final annealing is 430 ° C. or more and less than 500 ° C., 30 minutes. It is desirable to apply in 6 hours or less. More desirably, the intermediate annealing is performed at 220 ° C. or higher and 260 ° C. or lower for 1 hour or longer and 4 hours or shorter, and the final annealing is performed at 450 ° C. or higher and 480 ° C. or lower for 1 hour or longer and 4 hours or shorter.

  Through such a manufacturing process, the crystal orientations of the core layer and the outer layer can be controlled within the above-described range, and the diffusion of Sc, Zr, and V into the outer layer is suppressed as much as possible, and the strength as the core layer is assured. Can be sufficiently secured, and the growth or progress of the tunnel-type etch pit to the core layer can be effectively stopped.

  Further, from the viewpoint of more reliably controlling the crystal structures of the core layer and the outer layer after the final annealing described above, additional strain may be imparted between the intermediate annealing and the final annealing. It is recommended that the additional strain be applied by cold rolling with a rolling reduction of 8% or more and 30% or less or warm rolling that does not exceed the intermediate annealing temperature. If the rolling reduction is less than 8%, there is no effect of imparting additional strain, and if it exceeds 30%, the structure may not be obtained. The optimum value of the rolling reduction is 12% or more and 25% or less.

  In addition, when this additional work strain is imparted by tensile deformation instead of rolling, it is performed by tensile deformation at a temperature not exceeding the cold or intermediate annealing temperature of a working rate of 5% to 15%. It is desirable. If the processing rate is less than 5%, there is no effect of imparting additional strain, and if it exceeds 15%, the structure may not be obtained. The optimum value of the processing rate is 6% or more and 10% or less.

  The aluminum material according to the present embodiment exhibits characteristics of high strength and high bending strength when applied to any of a medium-high pressure application subjected to tunnel-type etching and a low-pressure application subjected to sponge etching. The effect is particularly great in the case of a high voltage formed by the above formation voltage. In this case, by controlling the pit distribution of the tunnel type etching, it becomes possible to reduce invalid etch pits generated in the process of forming a thick conversion film having an average thickness of 0.1 μm or more formed at a high conversion voltage.

  Such control of the etch pit distribution can be performed by providing an etch pit starting point (etch pit nucleus) in advance on the surface of the aluminum material. Etch pit nuclei can be applied by masking areas other than etch pit nuclei by printing resin, etc., by printing metal or metal ions or metal compounds as etch pit nuclei in a dot pattern, or by attaching them. For example, a method of diffusing the metal element by heat treatment can be exemplified.

  For example, a method of printing a metal compound or the like on the surface of an aluminum material is desirable because the operation is simple. In the printing method, the ink only needs to be able to uniformly contain the metal compound and be attached to the aluminum material. The ink is based on a solvent based on water, different in oiliness, kind of viscosity imparting agent, etc. Can be used regardless of The metal compound may be dissolved in the ink or may be dispersed without being dissolved. As the printing method, methods such as ink jet printing, electronic plate making, offset printing, gravure printing, letterpress printing, stencil printing, and the like can be applied, and the printing method is appropriately selected according to the ink adhesion amount, the printing pattern, and the like.

  Conventionally, even if etch pit nuclei are uniformly provided by such a method, the length of each etch pit becomes non-uniform depending on the surface state, and the core layer tends to become non-uniform. . According to the material of this embodiment, since the growth of the tunnel-type etch pit is forcibly stopped at the core layer, the control of the start point of the etch pit applied to the surface only needs to be focused on the start point distribution. The control efficiency of three-dimensional forms (etch pit interval, diameter, length, etc.) is remarkably enhanced.

  That is, for the aluminum material of this embodiment, by controlling the distribution of the starting points of the etch pits, the etch pits are distributed at a uniform interval, and the pit diameter is large and the length is uniform. Therefore, a high electrostatic capacity can be obtained.

  In order to exert such an effect, it is not necessary that all the etch pits are formed at the starting point provided in advance, and it is sufficient that at least 30% or more of the etch pits are formed at the starting point provided in advance. Further, in order to increase the capacitance, it is preferable that the surface area after etching is at least 10 times the projected area before etching.

  In the case of a low-pressure application in which sponge etching is performed, requirements regarding the structure of the core layer and the outer layer are not necessarily required. Further, in order to increase the capacitance, the surface area after etching needs to be 50 times or more the projected area before etching, and the thickness of the dielectric film coated on the etch pit forming portion is The average value is preferably 0.5 μm or less. If the average thickness exceeds 0.5 μm, the fine sponge etching layer is buried by the chemical conversion film, which impedes the impregnation of the electrolyte, and the amount of aluminum consumed during the growth of the chemical conversion film is too large. There is a possibility that the etching layer is divided and becomes invalid pits (Deth Pits).

Next, specific examples of the present invention will be described.
[Examples 1 to 31 (Tables 4 and 5)] [Comparative Examples 2 to 4 (Table 5)]
Homogenization treatment of aluminum ingots having a thickness of 200 mm, a width of 750 mm, and a length of 1200 mm made of various compositions shown in Tables 1 to 3 shown in Tables 1 to 3 produced by a semi-continuous casting method under conditions of 590 ° C. × 20 hours Thereafter, the surface was cut 12.5 mm on one side to a thickness of 175 mm.

  Next, the aluminum material used for the core layer was hot-rolled at a start temperature of 550 ° C. to produce a hot-rolled plate having a thickness of 50 mm, and was cut so as to have a length of 1250 mm.

  Further, in the combinations shown in the items of “Composition / Configuration” in Table 4 and Table 5, the aluminum material for the outer layer is superposed on both surfaces of the aluminum material for the core layer (total thickness is 400 mm), and the starting temperature is 550 ° C. Hot rolling was started to obtain a hot rolled sheet having a thickness of 10 mm. Subsequently, cold rolling was performed, and then intermediate annealing, additional rolling, and final annealing were performed under the conditions shown in Tables 4 and 5 to obtain an aluminum foil for electrolytic capacitor electrodes having a thickness of 0.12 mm.

In the obtained aluminum foil, the thickness of the core layer was 0.015 mm, which was 12.5% of the total thickness.
[Examples 32-35 (Table 5)]
An aluminum ingot having a composition of the circled number 3 shown in Table 1 produced by the semi-continuous casting method and having a thickness of 160 mm × width of 750 mm × length of 1200 mm is homogenized under conditions of 590 ° C. × 20 hours, one side 10.0 mm chamfering was performed to a thickness of 140 mm.

  On the other hand, about the aluminum material which consists of the composition of the round number 7 of Table 1 used for a core layer, the aluminum ingot of thickness 160mm x width 750mm x length 1200mm produced by the semi-continuous casting method is 590 degreeC x 20 hours. After homogenization treatment under the conditions, chamfering of 20.0 mm on one side was performed to a thickness of 120 mm.

  And after combining the aluminum ingot for outer layer on both surfaces of the aluminum material for core layer with the combination shown in the item of “Composition / Configuration” in Table 5 (400 mm in total thickness), hot at a start temperature of 550 ° C. Rolling was started and a hot-rolled sheet having a thickness of 10 mm was obtained. Subsequently, after cold rolling, intermediate annealing, imparting tensile strain, and final annealing were performed under the conditions shown in Table 5 to obtain an aluminum foil for electrolytic capacitor electrodes having a thickness of 0.15 mm.

In the obtained aluminum foil, the thickness of the core layer was 0.045 mm, which was 30% of the total thickness.
[Comparative Example 1 (Table 5)]
After homogenizing the aluminum ingot having a thickness of 420 mm, a width of 750 mm, and a length of 1200 mm made of the composition shown in the circled number 1 of Table 1 produced by a semi-continuous casting method under conditions of 590 ° C. × 20 hours, A single side of 10.0 mm was chamfered to a thickness of 400 mm.

  Subsequently, hot rolling was started at a starting temperature of 550 ° C., and a hot rolled plate having a thickness of 10 mm was obtained.

Subsequently, after cold rolling, final annealing was performed under the conditions shown in Table 5 to obtain an aluminum foil for electrolytic capacitor electrodes having a thickness of 0.12 mm.
[Example 36 (Table 6)]
After homogenizing an aluminum ingot having a thickness of 160 mm, a width of 750 mm, and a length of 1200 mm having the composition of the round numeral 1 shown in Table 1 prepared by a semi-continuous casting method at 590 ° C. for 20 hours, one side 10 0.0 mm chamfering was performed to a thickness of 140 mm.

  On the other hand, about the aluminum material which consists of the composition of the round number 7 of Table 1 used for a core layer, the aluminum ingot of thickness 160mm x width 750mm x length 1200mm produced by the semi-continuous casting method is 590 degreeC x 20 hours. After homogenization treatment under the conditions, chamfering of 20.0 mm on one side was performed to a thickness of 120 mm.

  And after superposing the aluminum ingot for outer layer on both surfaces of the aluminum material for core layer with the combination shown in the item of “composition / configuration” in Table 6 (total thickness is 400 mm), hot at a start temperature of 550 ° C. Rolling was started and a hot-rolled sheet having a thickness of 10 mm was obtained. Subsequently, after cold rolling, final annealing was performed under the conditions shown in Table 6 to obtain an aluminum foil for electrolytic capacitor electrodes having a thickness of 0.15 mm.

In the obtained aluminum foil, the thickness of the core layer was 0.045 mm, which was 30% of the total thickness.
[Comparative Example 5 (Table 6)]
After homogenizing the aluminum ingot having a thickness of 420 mm, a width of 750 mm, and a length of 1200 mm made of the composition shown in the circled number 1 of Table 1 produced by a semi-continuous casting method under conditions of 590 ° C. × 20 hours, A single side of 10.0 mm was chamfered to a thickness of 400 mm.

  Subsequently, hot rolling was started at a starting temperature of 550 ° C., and a hot rolled plate having a thickness of 10 mm was obtained.

Subsequently, after cold rolling, final annealing was performed under the conditions shown in Table 6 to obtain an aluminum foil for electrolytic capacitor electrodes having a thickness of 0.15 mm.

About each aluminum foil of Examples 1-35 obtained above and Comparative Examples 1-4, each crystal orientation occupation rate Score = [S _Cube + S _Goss ] / [S _Brass + S of a core layer and an outer layer by the following method. _C + S _S ], Sskin = S _Cube , concentration ratio of Sc, Zr, V between core layer and outer layer, crystal grain boundary distance between core layer, hardness ratio between core layer and outer layer, electrostatic capacity (DC etching evaluation), The bending strength and leakage current were examined.

Moreover, about Example 36 and the comparative example 5, the electrostatic capacitance (AC etching evaluation), bending strength, and leakage current were investigated.
<Crystal orientation measurement conditions>
Each crystal orientation occupancy ratio of the core layer and the outer layer Score = [S _Cube + S _Goss ] / [S _Brass + S _C + S _S ], S skin = S _Cube is measured by a Schottky field emission scanning electron microscope and an EBSP (Electron Backscattering Pattern). ) The methods were combined.

  First, as shown in FIG. 1, a sample is cut out so that a longitudinal section (TD direction) perpendicular to the rolling surface (ND direction) and the rolling direction (RD direction) is the sample surface, and this surface is polished and observed. Sample 1 was obtained. In FIG. 1, 2 is a core layer and 3 is an outer layer.

For this observation sample 1, EBSP analysis was performed with a measurement range of 100 μm × 150 μm and a measurement interval of 1.0 μm. The analysis data is vector-converted into orientation components viewed from the rolling surface (ND direction) and rolling direction (RD direction), and for each orientation component of S _Cube , S _Goss , S _Brass , S _C , S _S , The occupancy of each azimuth component with respect to the measurement area was calculated assuming that the azimuth difference is within 10 degrees and included in the azimuth component.

The core layer crystal orientation occupation ratio Score = [S _Cube + S _Goss ] / [S _Brass + S _C + S _S ] and the outer layer crystal orientation occupation ratio S skin = S _Cube were calculated separately.
<Evaluation method of element concentration ratio of core layer / outer layer>
For the core layer, the concentration of Sc, Zr, and V was measured by ICP emission spectroscopic analysis using 5% NaOH with a liquid temperature of 50 ° C. and using a sample made only by the core layer by dipping for a predetermined time. The sum Ccore (Sc + Zr + V) of the respective concentrations was determined.

For the outer layer, one side was masked with nail polish, 5% NaOH having a liquid temperature of 50 ° C. was used, and a sample made only of the outer layer by immersion for a predetermined time was used. Similarly to the core layer, Sc, Zr, The sum Cskin (Sc + Zr + V) of the concentration of V was determined, and Ccore (Sc + Zr + V) / Cskin (Sc + Zr + V) was determined by calculation. In addition, about each layer, immersion time was determined so that it might become the area | region of about 80% of each layer thickness by cross-sectional observation, and it used for ICP emission-spectral-analysis.
<Grain boundary spacing of core layer>
For the observation sample that was cut and polished so that the TD direction was the sample surface in the same manner as the crystal orientation occupancy measurement sample, Barker's solution (3 ± 1% borohydrofluoric acid aqueous solution) was used, and the liquid temperature Anodization was performed for 45 seconds at 27 to 30 ° C. and an applied voltage of 30 V, and the structure was observed with a polarizing microscope. The crystal grain boundary interval was obtained by drawing an arbitrary straight line perpendicular to the rolling surface and measuring the distance between the intersections intersecting the crystal grain boundary with respect to the arbitrary crystal grains of the core layer. The sampling number was 20 points, and the average value was used as the grain boundary interval.
<Method for evaluating hardness ratio of core layer / outer layer>
In the same manner as the crystal orientation occupancy measurement sample, the observation layer was cut and polished so that the TD direction was the surface of the sample, and the sample for observation was polished using a micro Vickers hardness meter according to JIS Z 2244. The hardness Hvcore and the hardness Hvskin of the outer layer were measured separately, and the ratio Hvskin / Hvcore was calculated.
<DC etching evaluation method, leakage current>
Using a mixed solution of 1.0 mol / L HCl and 3.5 mol / L H ₂ SO ₄ , after 30 seconds of immersion at a liquid temperature of 80 ° C., primary electrolysis for 120 seconds at a current density of 0.2 A / cm 2 Treated. Furthermore, chemical etching was performed at 90 ° C. for 900 seconds with the liquid having the same composition, washed with water and dried to complete the etching. Next, chemical conversion treatment was performed in a 10% boric acid bath 500 V, and subsequently, the capacitance was measured at a frequency of 120 Hz using an LCR meter in an 8% ammonium borate solution at room temperature.

  In addition, about the leakage current, the electric current value after completion | finish of a chemical conversion treatment was measured, and it was set as the leakage current.

By etching, the surface areas of the aluminum foils of Examples 1 to 35 were 25 to 35 times the projected area before etching. The average film thickness of the dielectric film formed on the surface was 0.6 to 0.9 μm.
<AC etching evaluation>
An etching solution is a mixture of 1.0 mol / L HCl and 0.02 mol / L H ₂ SO ₄ , liquid temperature 55 ° C., sine wave AC 30 Hz, current density AC 0.3 A / cm 2 (single side), time 300 sec. Etching was performed under the conditions of

  Furthermore, in an aqueous ammonium phosphate solution (1.5 g / L), a chemical conversion treatment was performed under the conditions of a current density of 5 mA / cm 2 and 20 V × 10 min, and a heat treatment was performed in the atmosphere at 500 ° C. × 5 min. Under conditions, re-formation was performed for 5 minutes to form a dielectric oxide film.

  Subsequently, the capacitance was measured at a frequency of 120 Hz using an LCR meter in an 8% ammonium borate solution at room temperature.

  In addition, about the leakage current, the electric current value after completion | finish of a chemical conversion treatment was measured, and it was set as the leakage current.

The average film thickness of the dielectric film formed on the surface of the aluminum foil of Example 36 by AC etching was 0.03 μm.
<Folding strength>
According to M.S. I. A T-type tester was used, the radius of curvature of the bent surface was 1 mmφ, and the load was 2.5N. Further, the bending angle was 90 degrees, the first bending was performed by 90 degrees, the second returning to the original, the third bending by 90 degrees to the opposite side, and the fourth returning to the original. The repetition rate of bending was 6 times / second.

The results obtained as described above are shown in Tables 4 to 6. In addition, about Example 1-35 of Table 4 and Table 5, and the electrostatic capacitance, folding strength, and leakage current of Comparative Examples 1-4, the electrostatic capacitance, folding strength, and leakage current of Comparative Example 4 were each 100. As for the capacitance, folding strength, and leakage current of Example 36 of Table 6 and Comparative Example 5, the capacitance, folding strength, and leakage current of Comparative Example 5 were set as 100, and the relative evaluation was performed. .

  As can be understood from the above tables, it can be seen that each example satisfying the requirements of the present invention has a larger capacitance than the comparative example, is excellent in bending strength, and has a small leakage current.

It is a figure which shows the EBSP measurement area and positional relationship of the crystal orientation occupation rate performed in the Example.

Explanation of symbols

1 Observation sample 1 (aluminum material)
2 core layer 3 outer layer

Claims (15)

The outer layer is laminated on at least one side of the core layer occupying 5% to 40% of the total thickness,
The core layer has an aluminum purity of 99.3% by mass or more, Si: 0.0005% by mass to 0.03% by mass, Fe; 0.0005% by mass to 0.03% by mass, Cu 0.0005 mass% or more and 0.015 mass% or less, Mn; 0.00003 mass% or more and 0.001 mass% or less, Mg; 0.00003 mass% or more and 0.005 mass% or less, Zn; 0.00003 mass % Or more and 0.005 mass% or less, Ti; 0.00003 mass% or more and 0.001 mass% or less, Cr; 0.00003 mass% or more and 0.003 mass% or less, Ni; 0.00003 mass% or more and 0.003 Mass% or less, Ga; 0.00003 mass% or more and 0.008 mass% or less, B; 0.00003 mass% or more and 0.002 mass% or less, V; 0.00003 mass% or more and 0.05 mass% or less Sc: 0.005 mass% or more and 0.1 mass% or less, Zr: 0.005 mass% or more and 0.2 mass% or less, and among the crystal orientation components viewed from the material surface, the deviation angle is 10 degrees The area occupation ratio of the crystal structure having the following crystal orientation component is
0.02 ≦ [S _Cube + S _Goss ] / [S _Brass + S _C + S _S ] ≦ 0.35
(However, S _Cube is a cubic orientation {100} <001>, S _Goss is a Goss orientation {110} <001>, S _Brass is a Brass orientation {110} <112>, and S _C is a C orientation {112} <111>. , S _S represents each crystal orientation component of S orientation {123} <634>),
The outer layer has an aluminum purity of 99.6% by mass or more , Si: 0.0005% by mass to 0.03% by mass, Fe; 0.0005% by mass to 0.03% by mass, Cu; 0.0005 mass% or more and 0.015 mass% or less, Mn: 0.00003 mass% or more and 0.001 mass% or less, Mg: 0.00003 mass% or more and 0.005 mass% or less, Zn: 0.00003 mass% 0.005 mass% or less, Ti: 0.00003 mass% or more and 0.001 mass% or less, Cr: 0.00003 mass% or more and 0.003 mass% or less, Ni: 0.00003 mass% or more and 0.003 mass% %: Ga: 0.00003 mass% or more and 0.005 mass% or less, B: 0.00003 mass% or more and 0.002 mass% or less, V: 0.00003 mass% or more and 0.003 mass% or less , Sc; 0.00003 mass% or more 0.003 wt% or less, Zr; 0.00003 containing mass% or more 0.003 wt% or less, and cube orientation {100} viewed from the surface of the material from <001> deviation angle Ri der area occupancy S _Cube 80% or more of the crystal structure having a 10 degrees or less in the crystal orientation components,
The sum Ccore (Sc + Zr + V) of the Sc and Zr, V concentrations of the core layer and the sum Cskin (Sc + Zr + V) of the Sc, Zr, V concentrations of the outer layer subjected to etching are as follows:
5 ≦ Ccore (Sc + Zr + V) / Cskin (Sc + Zr + V) ≦ 500
Electrolytic capacitor electrode aluminum material, characterized in Rukoto to have a following relationship. The core layer is Y: 0.00003% by mass or more and 0.03% by mass or less, La: 0.00003% by mass or more and 0.03% by mass or less, Ce: 0.00003% by mass or more and 0.03% by mass or less. The aluminum material for electrolytic capacitor electrodes according to claim 1, further comprising at least one kind. The outer layer is composed of Pb; 0.00003 mass% to 0.0003 mass%, Sn; 0.0003 mass% to 0.003 mass%, Bi; 0.00001 mass% to 0.00015 mass%, Sb The aluminum material for electrolytic capacitor electrodes according to claim 1, containing at least one kind of 0.0002 mass% or more and 0.002 mass% or less. The aluminum material for electrolytic capacitor electrodes according to any one of claims 1 to 3, wherein an interval between average crystal grain boundaries in the thickness direction of the core layer is 20 µm or less. The aluminum material for electrolytic capacitor electrodes according to any one of claims 1 to 4, wherein a ratio (Hvskin / Hvcore) of the hardness Hvcore of the core layer and the hardness Hvskin of the outer layer is 0.2 or more and 0.8 or less. The purity of aluminum is 99.3% by mass or more, and Si: 0.0005% by mass to 0.03% by mass, Fe: 0.0005% by mass to 0.03% by mass, Cu: 0.0005% by mass % Or more and 0.015 mass% or less, Mn: 0.00003 mass% or more and 0.001 mass% or less, Mg: 0.00003 mass% or more and 0.005 mass% or less, Zn: 0.00003 mass% or more and 0.005 Mass% or less, Ti: 0.00003 mass% or more and 0.001 mass% or less, Cr: 0.00003 mass% or more and 0.003 mass% or less, Ni: 0.00003 mass% or more and 0.003 mass% or less, Ga 0.00003 mass% or more and 0.008 mass% or less, B; 0.00003 mass% or more and 0.002 mass% or less, V; 0.00003 mass% or more and 0.05 mass% or less, Sc; 05 wt% to 0.1 wt% or less, Zr; on at least one surface of the core layer having a 0.005 wt% to 0.2 wt% or less,
The purity of aluminum is 99.6% by mass or more, and Si: 0.0005% by mass to 0.03% by mass, Fe: 0.0005% by mass to 0.03% by mass, Cu: 0.0005% by mass % Or more and 0.015 mass% or less, Mn: 0.00003 mass% or more and 0.001 mass% or less, Mg: 0.00003 mass% or more and 0.005 mass% or less, Zn: 0.00003 mass% or more and 0.005 Mass% or less, Ti: 0.00003 mass% or more and 0.001 mass% or less, Cr: 0.00003 mass% or more and 0.003 mass% or less, Ni: 0.00003 mass% or more and 0.003 mass% or less, Ga 0.00003 mass% or more and 0.005 mass% or less, B; 0.00003 mass% or more and 0.002 mass% or less, V; 0.00003 mass% or more and 0.003 mass% or less, Sc; 0 After laminating an outer layer having 00003 mass% or more and 0.003 mass% or less, Zr; 0.00003 mass% or more and 0.003 mass% or less, hot rolling and cold rolling are performed, and then final annealing is performed. On the occasion
From the hot rolling to the final annealing, at least one intermediate annealing is performed under the conditions of 200 ° C. or more and 300 ° C. or less and 30 minutes or more and 6 hours or less, and the rolling reduction is 8% between the intermediate annealing and the final annealing. Addition of additional strain is performed by cold rolling of 30% or less or warm rolling that does not exceed the intermediate annealing temperature, and the final annealing is performed under the conditions of 430 ° C. or more and less than 500 ° C., 30 minutes or more and 6 hours or less. The manufacturing method of the aluminum material for electrolytic capacitor electrodes characterized by the above-mentioned. The purity of aluminum is 99.3% by mass or more, and Si: 0.0005% by mass to 0.03% by mass, Fe: 0.0005% by mass to 0.03% by mass, Cu: 0.0005% by mass % Or more and 0.015 mass% or less, Mn: 0.00003 mass% or more and 0.001 mass% or less, Mg: 0.00003 mass% or more and 0.005 mass% or less, Zn: 0.00003 mass% or more and 0.005 Mass% or less, Ti: 0.00003 mass% or more and 0.001 mass% or less, Cr: 0.00003 mass% or more and 0.003 mass% or less, Ni: 0.00003 mass% or more and 0.003 mass% or less, Ga 0.00003 mass% or more and 0.008 mass% or less, B; 0.00003 mass% or more and 0.002 mass% or less, V; 0.00003 mass% or more and 0.05 mass% or less, Sc; 05 wt% to 0.1 wt% or less, Zr; on at least one surface of the core layer having a 0.005 wt% to 0.2 wt% or less,
The purity of aluminum is 99.6% by mass or more, and Si: 0.0005% by mass to 0.03% by mass, Fe: 0.0005% by mass to 0.03% by mass, Cu: 0.0005% by mass % Or more and 0.015 mass% or less, Mn: 0.00003 mass% or more and 0.001 mass% or less, Mg: 0.00003 mass% or more and 0.005 mass% or less, Zn: 0.00003 mass% or more and 0.005 Mass% or less, Ti: 0.00003 mass% or more and 0.001 mass% or less, Cr: 0.00003 mass% or more and 0.003 mass% or less, Ni: 0.00003 mass% or more and 0.003 mass% or less, Ga 0.00003 mass% or more and 0.005 mass% or less, B; 0.00003 mass% or more and 0.002 mass% or less, V; 0.00003 mass% or more and 0.003 mass% or less, Sc; 0 After laminating an outer layer having 00003 mass% or more and 0.003 mass% or less, Zr; 0.00003 mass% or more and 0.003 mass% or less, hot rolling and cold rolling are performed, and then final annealing is performed. On the occasion
Between the hot rolling and the final annealing, at least one intermediate annealing is performed under the conditions of 200 ° C. or more and 300 ° C. or less and 30 minutes or more and 6 hours or less, and the processing rate is 5% between the intermediate annealing and the final annealing. More than 15% cold tensile deformation or additional strain is applied by tensile deformation at a temperature not exceeding the intermediate annealing temperature, and the final annealing is performed at 430 ° C. or more and less than 500 ° C. for 30 minutes or more and 6 hours or less. The manufacturing method of the aluminum material for electrolytic capacitor electrodes characterized by implementing on conditions. The core layer is Y: 0.00003% by mass or more and 0.03% by mass or less, La: 0.00003% by mass or more and 0.03% by mass or less, Ce: 0.00003% by mass or more and 0.03% by mass or less. The manufacturing method of the aluminum material for electrolytic capacitor electrodes of Claim 6 or 7 which further contains at least 1 sort (s) .
The outer layer is composed of Pb; 0.00003 mass% to 0.0003 mass%, Sn; 0.0003 mass% to 0.003 mass%, Bi; 0.00001 mass% to 0.00015 mass%, Sb The method for producing an aluminum material for electrolytic capacitor electrodes according to claim 6 or 7 , comprising at least one element of 0.0002 mass% or more and 0.002 mass% or less. An aluminum electrolytic capacitor electrode material according to any one of claims 1 to 5, wherein the aluminum material for an electrolytic capacitor electrode is etched to have a surface area of 10 times or more of a projected area before etching. Anode material. The aluminum electrolytic capacitor anode material according to claim 10, wherein a dielectric film having an average film thickness of 0.1 μm or more is formed in the etch pit forming portion. When the aluminum material for electrolytic capacitor electrodes according to any one of claims 1 to 5 is subjected to an etching treatment, at least 30% or more of etch pits are generated by a starting point previously provided on the surface of the aluminum material. Manufacturing method of aluminum material. The outer layer is laminated on at least one side of the core layer occupying 5% to 40% of the total thickness,
The core layer has an aluminum purity of 99.3% by mass or more, Si: 0.0005% by mass to 0.03% by mass, Fe; 0.0005% by mass to 0.03% by mass, Cu 0.0005 mass% or more and 0.015 mass% or less, Mn; 0.00003 mass% or more and 0.001 mass% or less, Mg; 0.00003 mass% or more and 0.005 mass% or less, Zn; 0.00003 mass % Or more and 0.005 mass% or less, Ti; 0.00003 mass% or more and 0.001 mass% or less, Cr; 0.00003 mass% or more and 0.003 mass% or less, Ni; 0.00003 mass% or more and 0.003 Mass% or less, Ga; 0.00003 mass% or more and 0.008 mass% or less, B; 0.00003 mass% or more and 0.002 mass% or less, V; 0.00003 mass% or more and 0.05 mass% or less Sc: 0.005 mass% or more and 0.1 mass% or less, Zr: 0.005 mass% or more and 0.2 mass% or less, and among the crystal orientation components viewed from the material surface, the deviation angle is 10 degrees The area occupation ratio of the crystal structure having the following crystal orientation component is
0.02 ≦ [S _Cube + S _Goss ] / [S _Brass + S _C + S _S ] ≦ 0.35
(However, S _Cube is a cubic orientation {100} <001>, S _Goss is a Goss orientation {110} <001>, S _Brass is a Brass orientation {110} <112>, and S _C is a C orientation {112} <111>. , S _S represents each crystal orientation component of S orientation {123} <634>),
The outer layer has an aluminum purity of 99.6% by mass or more, Si; 0.0005% by mass to 0.03% by mass, Fe; 0.0005% by mass to 0.03% by mass, Cu; 0005 mass% to 0.015 mass%, Mn: 0.00003 mass% to 0.001 mass%, Mg: 0.00003 mass% to 0.005 mass%, Zn: 0.00003 mass% to 0 0.005% by mass or less, Ti: 0.00003% by mass or more and 0.001% by mass or less, Cr: 0.00003% by mass or more and 0.003% by mass or less, Ni: 0.00003% by mass or more and 0.003% by mass or less Ga; 0.00003 mass% to 0.005 mass%, B; 0.00003 mass% to 0.002 mass%, V; 0.00003 mass% to 0.003 mass%, S ; 0.00003% by mass or more and 0.003% by mass or less, Zr; 0.00003% by mass or more and 0.003% by mass or less, and a deviation angle from the cube orientation {100} <001> as viewed from the material surface The area occupancy S _{Cube of the} crystal structure having a crystal orientation component of 10 degrees or less is 80% or more,
The sum Ccore (Sc + Zr + V) of the Sc and Zr, V concentrations of the core layer and the sum Cskin (Sc + Zr + V) of the Sc, Zr, V concentrations of the outer layer subjected to etching are as follows:
5 ≦ Ccore (Sc + Zr + V) / Cskin (Sc + Zr + V) ≦ 500
An aluminum material for electrolytic capacitor electrodes for AC etching, characterized in that: The aluminum material for electrolytic capacitor electrode for AC etching according to claim 13 is subjected to AC etching, and a dielectric film having an average film thickness of 0.5 μm or less is formed in the etch pit forming portion. Anode material for aluminum electrolytic capacitors. An aluminum electrolytic capacitor, wherein the anode material according to any one of claims 10, 11, and 14 is used as an electrode material.

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