JPH10158769A - Brazing sheet made of aluminum alloy - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare a brazing sheet made of Al alloy, excellent in corrosion resistance and suitable for a heat exchanger to be joined and assembled by means of brazing, particularly noncorrosive flux brazing. SOLUTION: A core material 5, composed of an Al alloy having a composition consisting of, by mass, 0.5-2.0% Mn, 0.1-1.0% Cu, 0-1.0% Mg, 0-0.3% Ti, and the balance Al with inevitable impurities, is used. One side or both sides of this core material 5 are provided with intermediate layers 4, 4' each having 30-150μm thickness and composed of an Al alloy consisting of 0.01-2.0% Mn, 0.05-5.0% Zn, 0-0.3% Ti, <=0.05% Mg, <=0.05% Cu, and the balance Al with inevitable impurities. Further, the intermediate layers are clad with Al-Si alloy brazing filler metals 3, 3' to 30-150μm cladding thickness, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is suitable for brazing aluminum alloy heat exchangers for automobiles and various industrial applications, especially when brazing with a non-corrosive flux to join and assemble. The present invention relates to an Al alloy brazing sheet having excellent corrosion resistance. In this specification, the composition of the Al alloy is all mass%, but is simply abbreviated to%.

[0002]

2. Description of the Related Art When manufacturing a complicated structure such as a heat exchanger made of an Al alloy, a brazing method is an effective joining means. In this brazing method, Al or an Al alloy is used as a core material, and one or both surfaces are formed into various shapes using a brazing sheet clad with an Al alloy brazing material as a skin material, and these members are formed into a predetermined structure, for example. In the case of assembling into a heat exchanger and brazing with a non-corrosive flux (potassium fluoroaluminate complex), KAlF ₄ , K ₂ AlF ₅ , K ₃ Al
This is a method in which a mixed flux such as F ₆ is applied and then heated in a nitrogen reducing atmosphere to perform brazing.

[0003] Brazing sheets include various types of A for core material.
alloys and Al alloy brazing materials for skin materials have been developed, and these materials are now JIS-Z-3263 and JIS-
Standardized by H-4000. As a brazing sheet for brazing used in a heat exchanger, JIS3003 (representative example: Al-0.15% Cu-
1.1% Mn alloy), JIS6951 (representative example: Al-
0.4% Si-0.3% Cu-0.6% Mg alloy)
It is normal to use JIS 4045 (representative example Al-10% Si alloy) or JIS 4343 (representative example Al-7.5% Si alloy) brazing material as a skin material. Further, the brazing sheet has a thickness of about 0.3 to 1.5 mm, and the cladding ratio of the brazing material is 5 to 15 per one side with respect to the total thickness.
%, Clad on one or both sides.

As a heat exchanger made of an aluminum alloy having a hollow structure using such a brazing sheet, a drone cup type evaporator, an oil cooler, a radiator and the like are manufactured. For example, as shown in FIG. 4, a drone cup type evaporator 10 uses a brazing sheet in which the Al alloy brazing material is clad on both surfaces of the Al alloy core material as shown in FIGS. The refrigerant passage forming member 1 is manufactured by press molding, the members 1 are laminated as shown in FIG. 4, corrugated fins 2 are arranged between the laminated members 1, and side plates 7, 7
^{, The} refrigerant inlet pipe 8 and the refrigerant outlet pipe 9 are disposed and assembled, and brazed. The brazing is performed by heating to about 873K in a nitrogen gas atmosphere.

[0005]

As automobiles have become lighter, there has been a demand for heat exchangers for automobiles to be made thinner. On the other hand, the usage environment of automobiles varies,
Materials that can withstand all use conditions are required. In particular, in heat exchangers, corrosion resistance is the most important required property of the material, and the development of a brazing sheet having corrosion resistance has been awaited, and various studies have been made.

[0006] The corrosion resistance of a brazing sheet is related to the distribution of elements in the thickness direction of the material. Elements that contribute to the corrosion resistance of the material, such as Cu and Zn, are located at the center of the thickness when brazing heating is performed. The distribution is symmetrical about the axis. Therefore, when pitting occurs on the surface of the brazing sheet, the material whose pitting progresses on the surface side slower than the center of the plate thickness has a faster pitting progress after passing through the center of the plate thickness. In other words, it is not an exaggeration to say that the part contributing to the improvement of the corrosion resistance is half the plate thickness, and there is a limit to the improvement of the penetration life by the addition of the element to the core material.

Further, the addition of Cu increases the potential of aluminum, so that it is added to the core material of the brazing sheet for the purpose of improving corrosion resistance. However, Cu added to the core material diffuses into the brazing material melted during the brazing heating, and is discharged and concentrated to the eutectic portion when the brazing material solidifies after the brazing heating. Therefore, as the brazing sheet contains more Cu in the core material, the corrosion of the layer in which the brazing material is re-solidified proceeds more rapidly. Accordingly, there is a limit to the amount of elements such as Cu for improving the corrosion resistance with respect to the core material of the brazing sheet.

[0008] In the non-corrosive flux brazing,
The Mg cannot be added to the material because the flux reacts with the Mg in the material to produce a fluoride that inhibits brazing properties. Therefore, to prevent the diffusion of Mg in the core material into the brazing material, and to improve brazing properties,
JIS 1050, 1070, 110 between core material and brazing material
It has been proposed to provide an intermediate layer made of a 1XXX alloy material such as 0, and to provide an intermediate layer further added with Zn or the like to the intermediate layer material for the purpose of improving the corrosion resistance of the core material. (For example, JP-A-2-30394). However, this brazing sheet was still insufficient in terms of corrosion resistance and material strength. An object of the present invention is to solve the above-mentioned problems, and specifically, to find an Al alloy brazing sheet that is more excellent in terms of corrosion resistance and material strength.

[0009]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems. As a result, in order to improve the corrosion resistance of the brazing sheet member, the brazing material was added to the core material during brazing. In order to prevent the diffusion of Cu and other elements in the core material into the brazing material, an intermediate layer is provided between the brazing material and the core material. The present invention has been completed based on the finding that it is greatly related to corrosion resistance and material strength.

That is, the invention of claim 1 for solving the above-mentioned problem is that Mn: 0.5 to 2.0% and Cu: 0.1 to 2.0%.
Al containing 1.0%, Mg: 0 to 1.0%, Ti: 0 to 0.3%, with the balance being Al and unavoidable impurities
On one or both surfaces of the alloy core material, Mn: 0.01-2.
0%, Zn: 0.05 to 5.0%, Ti: 0 to 0.3%
, Mg: 0.05% or less, Cu: 0.05
%, The balance being an Al alloy consisting of Al and unavoidable impurities, provided with an intermediate layer having a thickness of 30 to 150 μm, and an Al—Si alloy brazing material of 30 to 150 μm on the intermediate layer. It is a brazing sheet made of an Al alloy, which is characterized by being combined with a clad thickness of

According to a second aspect of the present invention, the Al-brazing alloy brazing material according to the first aspect, wherein the Al-Si alloy brazing material further contains 0.05 to 0.5% of Sn. It is a sheet.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. The invention according to claim 1 provides Mn: 0.5 to 2.0.
%, Cu: 0.1 to 1.0%, Mg: 0 to 1.0%, T
i: 0 to 0.3%, the balance being Al and an unavoidable impurity.
n: 0.01 to 2.0%, Zn: 0.05 to 5.0%,
Ti: 0 to 0.3%, Mg: 0.05% or less, Cu: 0.05% or less, the balance being an Al alloy consisting of Al and unavoidable impurities. Provided an intermediate layer having a thickness of 30 to 150 μm, and A was provided on the intermediate layer.
The gist of the present invention is an Al alloy brazing sheet in which an l-Si alloy brazing material is combined with a cladding thickness of 30 to 150 μm. That is, Al-Mn-Cu- (M
g) On one or both sides of the (Ti) alloy core material, Al-
This is a brazing sheet in which an intermediate layer of a Mn-Zn- (Ti) alloy having a thickness of 30 to 150 μm is provided, and an Al-Si alloy brazing material is further clad on the intermediate layer to a thickness of 30 to 150 μm.

The structure of the cross section of the brazing sheet will be described with reference to the drawings. As shown in FIGS. 1 (a), (b), (c) and (d), there are four modes depending on the purpose of use. FIG. 1A shows a structure ⁱⁿ which intermediate layers 4 ^and 4 are provided on both surfaces of a core material 5 and brazing materials 3 ^and 3 are provided on both intermediate layers. Oil coolers and car heater tubes (with inner fins) when the corrosion resistance of the inner and outer surfaces is important. (B) shows a structure in which an intermediate layer 4 is provided on one surface of a core material 5 and a brazing material 3 is provided on this intermediate layer. 3
^The actual use is, for example, when importance is placed on the corrosion resistance of the outer surface, such as a drone cup type evaporator as shown in FIG. 4 (in this case, since the inner surface is Freon gas, the corrosion resistance is not very important). Not).

FIG. 3C shows a case in which an intermediate layer 4 is provided on one surface of a core material 5 and a brazing material 3 is provided on the intermediate layer. There is no brazing material 3 ^and it is bare. As an actual application, for example, when importance is attached to the corrosion resistance of the outer surface, it is a parallel flow type condenser tube (electrically welded tube) or the like (in this case, the inner surface is made of chlorofluorocarbon, so that the corrosion resistance is not so important). (D), an intermediate layer 4 is provided on one surface of a core material 5, a brazing material 3 is provided on this intermediate layer, and 7 mm is provided on the other surface of the core material 5.
A sacrificial material 6 such as 072 (Al-Zn alloy) is provided. As an actual application, for example, a tube of a radiator (an electric resistance welded tube) is used (in this case, the inner surface is water and the outer surface is outside air).

The specific structure of the brazing sheet according to the present invention is as described above. Next, the Al alloy used for the core material of the sheet of the present invention will be described. The meanings of the added elements of the core alloy and the reasons for limiting the added range are as follows. Cu is used in an amount of 0.1 to improve corrosion resistance.
If the amount is less than the lower limit, the effect is weak. If the amount exceeds the upper limit, intergranular corrosion is likely to occur, and the amount of diffusion of the brazing material into the core material increases, so that the corrosion resistance decreases. Let it. Therefore, the range is 0.1 to 1.0%, and more preferably 0.15 to 0.5%.

Mn is 0.5 to 2.0 for improving strength.
However, if the amount is less than the lower limit, the effect of improving the strength is small. If the amount exceeds the upper limit, the amount of diffusion of the brazing material into the core material during brazing heating increases, thereby deteriorating brazing properties and corrosion resistance. Therefore, the range is 0.5 to 2.0%,
More preferably, it is 0.8 to 1.5%.

Mg is added in an amount of 0 to 1.0% for improving the strength. The meaning of 0 to 1.0% means that 0% (less than 0.01%) is the case where no addition is made, and when added, it is 0.01 to 1.0%. If the addition amount exceeds 1.0%, the diffusion amount of the brazing material into the core material during brazing heating increases,
Decreases brazing and corrosion resistance. Therefore, the range is set to 0 to 1.0%. Specifically, it is preferable to add as follows according to the purpose of use. That is, in the case of a four-layer material (b in FIG. 1) in which an intermediate layer is provided only on one side between the brazing material and the core material and the other surface is a brazing material, Mg is not added to the core material, or amount of .05% or less, brazing with non-corrosive flux (Figure 1 b brazing material ^3, the brazing of the side) preferred in view of. In the case of a five-layer material (FIG. 1A) in which an intermediate layer is provided between the brazing material and the core material,
In the case of a three-layer material or a four-layer material (c and d in FIG. 1) in which an intermediate layer is provided only on one side between the brazing material and the core material but has no brazing material on the other surface, addition of Mg to the core material Is 0.05 to 1.0%, preferably 0.1 to 0.6%.

Ti is used in an amount of 0 to improve corrosion resistance.
Add 0.3%. The meaning of 0 to 0.3% is 0% (0.
(Less than 01%) is the case where it is not added at all, and when added, it is 0.01 to 0.3%. If the addition amount exceeds 0.3%, coarse Ti crystals are formed, which adversely affects corrosion resistance. Therefore, the range of Ti is set to 0 to 0.3%, but whether to add Ti is determined by appropriately selecting according to the use of the product. In addition, when adding, it is more preferable to set it to about 0.05 to 0.2%.

As the unavoidable impurities other than the above elements in the core material, there are Si, Fe, Cr, Zn, etc., but generally accepted ranges, ie, Si is 0.6% or less, and Fe is 0.7% or less. , Cr is 0.20% or less, and Zn is 0.40% or less.
%, There is no particular problem. However, as for Si and Fe, it is more preferable to make Si 0.20% or less and Fe 0.20% or less.

Next, Al—Mn—Zn— (T) used for the intermediate layer material of the Al alloy brazing sheet according to the present invention.
i) The alloy will be described. The additive element Mn contributes to the improvement of the strength of the material, and Zn and Ti contribute to the improvement of the corrosion resistance of the material. The details are as follows. Mn is added in an amount of 0.01 to 2.0% to improve strength.
%, The effect of improving the strength is small, and if it exceeds 2.0%, the amount of diffusion of the brazing material into the intermediate layer material during brazing heating increases, thereby deteriorating the corrosion resistance. Therefore, the range is 0.01
To 2.0%, but more preferably 0.3 to 1.3%.

Zn is used in an amount of 0.0 to improve corrosion resistance.
If it is less than the lower limit, the effect of improving the corrosion resistance is small, and if it exceeds the upper limit, the self-corrosion resistance of the intermediate layer is reduced and the corrosion resistance as a brazing sheet is impaired. Therefore, the range is 0.05 to 5.0%, but more preferably 0.5 to 3.0%.

Ti is used in an amount of 0 to improve corrosion resistance.
Add 0.3%. The meaning of 0 to 0.3% is 0% (0.
(Less than 01%) is the case where it is not added at all, and when added, it is 0.01 to 0.3%. If the addition amount exceeds 0.3%, coarse Ti crystals are formed, which adversely affects corrosion resistance. Therefore, the range of Ti is set to 0 to 0.3%, but whether to add Ti is determined by appropriately selecting according to the use of the product. In addition, when adding, it is more preferable to set it to about 0.05 to 0.2%.

Mg is restricted to 0.05% or less because it forms a flux and a fluoride during brazing of a non-corrosive flux and impairs brazing properties. Cu diffuses into the brazing material during brazing and impairs corrosion resistance.
Restrict to 05% or less.

The inevitable impurities other than the above elements in the Al alloy material of the intermediate layer include Si, Fe, Cr and the like.
If Fe is 0.7% or less and Cr is 0.20% or less, there is no particular problem in terms of workability, corrosion resistance, and the like. Where S
For i and Fe, Si 0.20% or less, Fe 0.2
More preferably, it is 0% or less.

Next, the configuration of the brazing sheet according to the present invention is such that one (one side) or both (two sides) of the core material is used.
Then, an intermediate layer material made of the Al alloy is provided, and a brazing material is further clad thereon. The specific structure is shown in FIGS. 1 (a), 1 (b), 1 (c) and 1 (d). This point has already been described. The method of providing the intermediate layer material in the brazing sheet is such that the brazing material is provided on the core material and is provided between the core material and the brazing material on the harsh side of the corrosive environment. For example, in the case of a drone cup type evaporator as shown in FIG. 4, it is the side corresponding to the outside of the brazing sheet in contact with the outside air (FIG. 1b), and in the case of a car heater having a drone cup type inner fin. (Inner surface is water, outer surface is outside air), the corrosive environment is harsh on both the inner and outer surfaces, and it is provided on both sides of the core material of the brazing sheet (FIG. 1a).

The thickness of the intermediate layer of the Al alloy brazing sheet according to the present invention is 30 to 150 μm. The reason why the thickness of the intermediate layer is 30 μm or more is that if it is less than 30 μm, Cu of the core material diffuses to the brazing material through the intermediate layer at the time of brazing heating. The Cu that has reached the brazing material is discharged to the eutectic portion when the brazing material is melted and solidified, and is concentrated, thereby lowering the corrosion resistance. Further, the reason why the thickness of the intermediate layer is set to 150 μm or less is that if the intermediate layer is too thick with respect to the thickness of the brazing sheet, the material strength is reduced and molding becomes difficult, and sacrificial corrosion of the core material is prevented. This is because, when the corrosion progresses due to too many portions, the remaining plate thickness becomes thin, and it becomes impossible to withstand the internal pressure of the heat exchanger.

There is no particular limitation on the Al-Si alloy brazing material used in the present invention. 4045 used for ordinary non-corrosive flux brazing (typical Al-10
% Si alloy), 4343 (Representative example: Al-7% Si alloy)
Etc. can be used. Also, an Al-Si alloy to which Bi or the like is added for improving the fluidity of the solder, or an Al-Si alloy to which Sn, Zn, or In is added for imparting a sacrificial effect can be used. As for the clad ratio of the brazing material clad on the core material, a normal clad ratio, that is, 5 to 20% per one side with respect to the entire plate thickness can be used.
The thickness of the brazing material clad on the intermediate layer in the present invention is 30 to 150 μm. The reason for this limitation is that when the thickness is less than 30 μm, the amount of brazing material is small and sufficient brazing is not performed. On the other hand, if the thickness exceeds 150 μm, the amount of the brazing material becomes too large, and a phenomenon occurs in which the core material is eroded in a portion where the brazing material such as a fillet portion accumulates. When the intermediate layer is provided only on one surface of the core material, the other surface of the core material may be clad with a brazing material (b in FIG. 1) or naked without cladding the brazing material (FIG. 1B). 1c), the sacrificial material may be clad (FIG. 1d).

The structure of the Al alloy brazing sheet according to the present invention is as described above. Next, the second aspect of the present invention will be described. The invention according to claim 2 is an embodiment of the invention according to claim 1, and the Al-S according to claim 1 is an embodiment.
An Al alloy brazing sheet containing 0.05 to 0.5% of Sn in an i-type alloy brazing material. Since Sn is discharged to the eutectic portion when the brazing material solidifies after the brazing heating, the potential of the eutectic portion can be neutralized, and the corrosion resistance of the brazing sheet surface after the brazing heating can be further improved. . If the amount is less than the lower limit, the effect is not obtained. If the amount exceeds the upper limit, the hot rolling property is reduced and the production becomes difficult. In addition, the corrosion resistance of the surface after brazing is reduced, and the progress of corrosion is promoted. Therefore, the amount of addition is 0.05-0.
Although it is set to 5%, it is more preferably set to 0.05 to 0.2%. Other requirements are the same as those of the first aspect.

[0029]

Next, examples of the present invention (examples of the present invention) will be described in more detail together with comparative examples. Example 1 Core materials and intermediate layer materials having various alloy compositions shown in Table 1 were prepared. The core material and the intermediate layer material are combined as shown in Table 1, the intermediate layer material is combined on one side of the core material, and the brazing material made of JIS 4045 alloy is clad on both surfaces thereof (the cladding ratio is based on the total thickness). 10% per side)
did. The cladding thickness of the intermediate layer was variously changed. For the rolling material thus adjusted, soaking, hot rolling, intermediate annealing and cold rolling are performed according to a conventional method,
1.0 mm thick brazing sheet (intermediate layer thickness 2
0-200 μm, brazing material thickness 100 μm). Table 1 shows the configurations of these various brazing sheets. The thus obtained brazing sheets (No. 1 to 18) shown in Table 1 were washed and finish-annealed, and then coated with a non-corrosive flux (mixed flux of KAlF ₄ and K ₂ AlF ₅ ) at 10 g / m ^2. Then, in a nitrogen gas atmosphere, brazing and heating were performed at 873 K × 3 minutes to obtain a test material.

JIS No. 5 test pieces were prepared using these test materials, and the tensile strength was measured. Press molding was performed using these test materials. Whether or not a sufficient molding height was obtained was evaluated by measuring the overhang height of the molded product. Further, one surface (the side without the intermediate layer) of all the test materials was covered with a resin, and a corrosion test (CASS test) was performed on the surface on the intermediate layer side. 500 hours after start of test and 1000
After a lapse of time, the test material was taken out, the surface corrosion products were removed, and the corrosion state of the material was evaluated. For the evaluation, the pit depth of the maximum pit was measured by the depth of focus method using an optical microscope. Table 1 also shows the results of these measurements.

[0031]

[Table 1]

As is clear from Table 1, the brazing sheet according to the present invention (Example of the present invention) is superior in strength as compared with the conventional example, is superior in corrosion resistance as compared with the comparative example, and has overall material characteristics. It turns out that it is excellent. In addition, the moldability of the brazing sheet according to the present invention is maintained at the conventional level as is clear from Table 1.

Example 2 Core materials and intermediate layer materials having various alloy compositions shown in Table 1 were prepared. The core material and the intermediate layer material are combined as shown in Table 1, and the intermediate layer material is combined on one side of the core material, and further on both sides thereof, 0.1 to 0.6% of Sn is further contained in the JIS 4045 alloy. The brazing material was clad (the cladding ratio was 10% per one side with respect to the entire plate thickness). The rolling material thus combined is subjected to soaking, hot rolling, intermediate annealing, and cold rolling according to a conventional method, and is formed into a brazing sheet having a thickness of 1.0 mm (intermediate layer thickness of 100 μm, brazing material thickness). 100 μm). Table 2 shows the configurations of these various brazing sheets. The brazing sheets shown in Table 2 (No. 19)
After washing and finish annealing, the same flux as in Example 1 was applied at a rate of 10 g / m ² , and was heated in a nitrogen gas atmosphere at 873 K × 3 minutes for brazing, thereby obtaining a test material. did. One surface of these test materials (the side without the intermediate layer) was coated with resin, and the surface on the intermediate layer side was subjected to a corrosion test (CAS
S test). 500 hours after start of test, 1000
After a lapse of time, the test material was taken out, the surface corrosion products were removed, and the corrosion state of the material was evaluated. For the evaluation, the pit depth of the maximum pit was measured by the depth of focus method using an optical microscope. The measurement results are also shown in Table 2.

[0034]

[Table 2]

As is clear from Table 2, the brazing sheet according to the present invention containing 0.1 to 0.2% of Sn in the brazing material (Example of the present invention) has more improved corrosion resistance than the brazing sheet containing no Sn. (See Table 1 of Example 1). In addition, it can be seen that the brazing material containing 0.6% of Sn (Comparative Example) has rather poor corrosion resistance.

[0036]

As described in detail above, the present invention significantly improves the corrosion resistance by providing an intermediate layer between the core material and the brazing material on the harsh side of the corrosive environment in using the Al alloy brazing sheet. Therefore, when the brazing sheet according to the present invention is used for a heat exchanger, the corrosion life of the heat exchanger can be significantly improved. In addition, there is no problem in strength and moldability, and there is an industrially remarkable effect.

[Brief description of the drawings]

FIG. 1 is a diagram showing a cross-sectional structure of an Al alloy brazing sheet according to the present invention, wherein (a), (b), (c), and (d).
Is the embodiment.

FIG. 2 is a plan view showing a refrigerant passage forming member for a drone cup evaporator.

FIG. 3 is a sectional view taken along line B-B 'of FIG.

FIG. 4 is an explanatory view showing an example of a heat exchanger (Drone cup evaporator), and is a schematic sectional view thereof.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 refrigerant forming member for drone cup evaporator 2 fin 3 ^, 3 ^, brazing material 4 ^, 4 ^, intermediate layer material 5 core material 6 sacrificial material 7 ^, 7 ^, side plate 8 refrigerant inlet pipe 9 refrigerant outlet pipe 10 heat exchanger ( Delon cup evaporator)

Claims (2)

[Claims] 1. Mn: 0.5 to 2.0 mass% (hereinafter simply referred to as%), Cu: 0.1 to 1.0%, Mg: 0 to 0%
One or both sides of an Al alloy core material containing 1.0%, Ti: 0 to 0.3%, and the balance being Al and inevitable impurities, Mn: 0.01 to 2.0%, Zn: 0 .05
-5.0%, Ti: 0-0.3%, and further Mg:
0.05% or less, Cu: regulated to 0.05% or less, the balance being an Al alloy composed of Al and unavoidable impurities, provided with an intermediate layer having a thickness of 30 to 150 μm, and provided on the intermediate layer. A brazing sheet made of an Al alloy, wherein an Al-Si alloy brazing material is combined with a cladding thickness of 30 to 150 µm. 2. The Al—Si alloy brazing material further comprises S
The Al alloy brazing sheet according to claim 1, wherein n: 0.05 to 0.5% is contained.