ALUMINUM ALLOY CLAD MATERIAL

Abstract

An AlSiMgBi-based brazing material containing Si: 6.0% to 14.0%, Fe: 0.05% to 0.3%, Mg: 0.02% to 1.5%, Bi: 0.05% to 0.25%, Sr: 0.0001% to 0.1%, and a balance of Al and inevitable impurities, and satisfies (Bi+Mg)Sr0.1, is disposed on both surfaces of a core material, MgBi-based compounds of the brazing material with a diameter of 0.1 m or more and less than 5.0 m in terms of equivalent circle diameter are more than 20 in number in 10,000 m.sup.2 and the MgBi-based compounds with diameter of 5.0 m or more are less than 2 in number in 10,000 m.sup.2, the core material contains Mn: 0.8% to 1.8%, Si: 0.01% to 1.0%, Fe: 0.1% to 0.5%, and a balance of Al and inevitable impurities, and a cathode current density of a brazing material layer after a brazing heat treatment is 0.1 mA/cm.sup.2 or less.

Claims

1. An aluminum alloy clad material comprising: an AlSiMgBi brazing material disposed on both surfaces of a core material, the AlSiMgB brazing material containing, by mass %, Si: 6.0% to 14.0%, Fe: 0.05% to 0.3%, Mg: 0.02% to 1.5%, Bi: 0.05% to 0.25%, Sr: 0.0001% to 0.1%, and a balance consisting of Al and inevitable impurities and satisfying a relationship of (Bi+Mg)Sr0.1 in amounts of elements by mass %, wherein Mg-Ri compounds contained in the AlSiMgBi brazing material and having a diameter of 0.1 m or more and less than 5.0 m in terms of equivalent circle diameter are more than 20 in number per 10,000-m.sup.2 visual field and the MgBi compounds having a diameter of 5.0 m or more are less than 2 in number per 10,000-m.sup.2 visual field when observed in a surface layer plane direction before brazing, and the core material contains, by mass %, Mn: 0.8% to 1.8%, Si: 0.01% to 1.0%, Fe: 0.1% to 0.5%, and a balance consisting of Al and inevitable impurities, and a cathode current density of a brazing material layer measured at room temperature in a 5% NaCl solution at a pH of 3 after a brazing heat treatment is 0.1 mA/cm.sup.2 or less.

2. The aluminum alloy clad material according to claim 1, wherein the core material further contains, by mass %, Cu: 0.005% to 0.3%.

3. The aluminum alloy clad material according to claim 1, wherein the core material further contains, by mass %, Mg: 0.1% to 0.7%.

4. The aluminum alloy clad material according to claim 2, wherein the core material further contains, by mass %, Mg: 0.1% to 0.7%.

5. The aluminum alloy clad material according to claim 1, wherein the core material further contains, by mass %, Zn: 0.2% to 1.6%.

6. The aluminum alloy clad material according to claim 2, wherein the core material further contains, by mass %, Zn: 0.2% to 1.6%.

7. The aluminum alloy clad material according to claim 3, wherein the core material further contains, by mass %, Zn: 0.2% to 1.6%.

8. The aluminum alloy clad material according to claim 4, wherein the core material further contains, by mass %, Zn: 0.2% to 1.6%.

9. The aluminum alloy clad material according to claim 1, wherein the brazing material further contains, by mass %, Mn: 0.05% to 0.3%.

10. The aluminum alloy clad material according to claim 2, wherein the brazing material further contains, by mass %, Mn: 0.05% to 0.3%.

11. The aluminum alloy clad material according to claim 3, wherein the brazing material further contains, by mass %, Mn: 0.05% to 0.3%.

12. The aluminum alloy clad material according to claim 4, wherein the brazing material further contains, by mass %, Mn: 0.05% to 0.3%.

13. The aluminum alloy clad material according to claim 5, wherein the brazing material further contains, by mass %, Mn: 0.05% to 0.3%.

14. The aluminum alloy clad material according to claim 6, wherein the brazing material further contains, by mass %, Mn: 0.05% to 0.3%.

15. The aluminum alloy clad material according to claim 7, wherein the brazing material further contains, by mass %, Mn: 0.05% to 0.3%.

16. The aluminum alloy clad material according to claim 8, wherein the brazing material further contains, by mass %, Mn: 0.05% to 0.3%.

17. The aluminum alloy clad material according to claim 1, wherein a concentration of Mg on a surface of the brazing material at a braze melting temperature is in a range of 0.15% to 1.0%.

18. The aluminum alloy clad material according to claim 3, wherein a concentration of Mg on a surface of the brazing material at a braze melting temperature is in a range of 0.15% to 1.0%.

19. The aluminum alloy clad material according to claim 5, wherein a concentration of Mg on a surface of the brazing material at a braze melting temperature is in a range of 0.15% to 1.0%.

20. The aluminum alloy clad material according to claim 7, wherein a concentration of Mg on a surface of the brazing material at a braze melting temperature is in a range of 0.15% to 1.0%.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0090] FIG. 1 is a view illustrating a brazing sheet for flux-free brazing according to an embodiment of the present invention.

[0091] FIG. 2 is a perspective view illustrating an aluminum heat exchanger for a vehicle according to the embodiment of the present invention.

[0092] FIG. 3 is a view illustrating a brazing evaluation model in an example of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0093] Hereinafter, an embodiment of the present invention will be described.

[0094] An aluminum alloy is melted to be adjusted to the composition of the present invention. The melting can be performed by a semi-continuous casting method.

[0095] In the present embodiment, in order to disperse a fine MgBi compound at the time before brazing, Mg and Bi are dissolved in an ingot as a solid solution by performing casing at a high cooling rate from a high molten metal temperature during casting of a brazing material. Specifically, the solid solubility of Mg and Bi can be increased by setting the molten metal temperature to 700 C. or higher.

[0096] The obtained aluminum alloy ingot is subjected to a homogenization treatment under predetermined conditions. When the homogenization treatment temperature is low, a coarse MgBi compound is precipitated and it is difficult to obtain the distributed state of the MgBi compound of the present invention at the time before the brazing. Therefore, it is desirable to perform the treatment at a treatment temperature of 400 C. or higher for 1 to 10 hours.

[0097] Next, the brazing material is assembled with a core material and the like and is subjected to hot clad rolling. At this time, in the present invention, the MgBi compound is adjusted to a predetermined size and number density by controlling a rolling time at a predetermined temperature during hot rolling, an equivalent strain from the start to the end of the hot rolling, a hot rolling finish temperature, and a cooling rate after the hot rolling.

[0098] First, by satisfying the rolling time in a predetermined temperature range during the hot rolling, precipitation of the MgBi compound having a predetermined size defined in the present invention is promoted in an environment where dynamic strain is applied. Specifically, the precipitation of the fine MgBi compound is promoted by setting the rolling time during which the material temperature during the hot rolling is between 400 C. and 500 C. to 10 minutes or more.

[0099] Furthermore, by controlling the equivalent strain from the start to the end of the hot rolling, a coarse MgBi crystallized product generated during the casting can be crushed and refined, and the number density thereof can be increased. Specifically, the MgBi crystallized product is sufficiently refined by adjusting a slab thickness and a finish thickness so that the equivalent strains represented by Formula (1) satisfies >5.0, thereby increasing the number density

[0100] =(2/3)1n(t.sub.0/t) . . . Formula (1)

[0101] t.sub.0: Hot rolling start thickness (slab thickness)

[0102] t: Hot rolling finish thickness

[0103] Furthermore, when the hot rolling finish temperature is high and a state without dynamic strain is maintained, or when the cooling rate after the hot rolling is slow, a coarser MgBi compound than desired by the present invention is precipitated at grain boundaries and the like. Therefore, by securing a cooling rate of a certain level or more by reducing the hot rolling finish temperature to a predetermined temperature, the precipitation of a coarse MgBi compound is suppressed. Specifically, the precipitation of a coarse MgBi compound is suppressed by setting the hot rolling finish temperature to 250 C. to 350 C. and controlling the cooling rate from the finish temperature to 200 C. to be faster than 20 C./hr.

[0104] Thereafter, a brazing sheet of the present invention is obtained through cold rolling or the like.

[0105] In the cold rolling, for example, cold rolling can be performed with a total reduction rate of 75% or more, process annealing can be performed at a temperature of 200 C. to 450 C., and then final rolling with a reduction rate of 40% can be performed. In cold rolling, the MgBi compound is less likely to be crushed and does not deviate from the size and number density targeted by the present invention, so that the conditions are not particularly limited. Further, process annealing may not be performed, or H2n grade that has been finished by final annealing may be applied.

[0106] In an aluminum alloy clad material 1 made of the brazing sheet obtained in the above process, an aluminum alloy brazing material 3A is disposed on one surface of an aluminum alloy core material 2, and an aluminum alloy brazing material 3B is disposed on the other surface of the aluminum alloy core material 2. The aluminum alloy clad material 1 is subjected to brazing as an assembly combined with other constituent members 10 (fin, tube, side plate, and the like) as the constituent members of the heat exchanger. The aluminum alloy brazing materials 3A and 3B may have the same composition, or may have different compositions. Furthermore, the thicknesses thereof may be the same or different.

[0107] The assembly is disposed in a heating furnace having a non-oxidizing atmosphere under a normal pressure. A non-oxidizing gas can be constituted using an inert gas such as nitrogen gas, argon, a reducing gas such as hydrogen or ammonia, or a mixed gas thereof. Although the pressure of the atmosphere in a brazing furnace is basically the normal pressure, for example, in order to improve a gas replacement efficiency inside a product, a medium to low vacuum of about 100 kPa to 0.1 Pa in a temperature range before melting the brazing material may be employed, or a positive pressure of 5 to 100 Pa from the atmospheric pressure may be employed in order to suppress the infiltration of outside air (atmosphere) into the furnace.

[0108] The heating furnace does not need to have a sealed space, and may be a tunnel type having a carry-in port and a carry-out port for the brazing material. Even in such a heating furnace, non-oxidizing properties are maintained by continuously blowing the inert gas into the furnace. The non-oxidizing atmosphere desirably has an oxygen concentration of 50 ppm or less by volume ratio.

[0109] In the above atmosphere, for example, heating is performed at a temperature rising rate of 10 to 200 C./min, and braze joining is performed under heat treatment conditions in which an attainment temperature of the assembly is 559 C. to 630 C.

[0110] Under the brazing conditions, the brazing time is shortened as the temperature rising rate is increased, so that the growth of an oxide film on a material surface is suppressed and the brazability is improved. Brazing is possible when the attainment temperature is equal to or higher than at least the solidus temperature of the brazing material. However, the brazing material which flows increases in amount as the temperature approaches the liquidus temperature, and a good joined state is easily obtained at a joint having an open portion. However, when the temperature is too high, brazing erosion tends to proceed, and the structural dimensional accuracy of the assembly after brazing decreases, which is not preferable.

[0111] FIG. 2 illustrates an aluminum heat exchanger 5 in which fins 6 are formed using the aluminum alloy clad material 1 and a tube 7 made of an aluminum alloy is used as a brazing target material. The fin 6 and the tube 7 are assembled with a reinforcing member 8 and a header plate 9 to obtain the aluminum heat exchanger 5 for a vehicle or the like by flux-free brazing.

EXAMPLE 1

[0112] Various brazing sheets having the compositions shown in Tables 1 and 2 or Tables 4 and 5 (balance consisting of Al and inevitable impurities) were produced into hot rolled sheets under the casting conditions, homogenization conditions (brazing material), and hot rolling conditions shown in Table 7. In addition, in the component indicates that the content is 0 or the amount as an inevitable impurity. Thereafter, cold rolled sheets having a thickness of 0.06 nun and having an H14 equivalent grade were produced by cold rolling including process annealing. The clad ratio of the brazing material was 8% for both surfaces. Moreover, as a brazing target member, an aluminum bare material (0.3 mm thickness) of A3003 alloy and H14 was prepared.

[0113] The aluminum clad fin material was subjected to corrugating, and the corrugated fin and A3003 were combined to form cores having a 15-stage tube and a length of 300 mm as brazing evaluation models. The core was heated to 600 C. and held for 5 minutes in a brazing furnace in a nitrogen atmosphere (oxygen content 30 ppm), and the brazed state was evaluated. Here, a heat input amount from room temperature to 550 C. (the integral of the product of the diffusion coefficient of Zn and time during a brazing heat treatment) was set to 610.sup.11 m.sup.2, a heat input amount until the completion of the brazing was set to 810.sup.10 m.sup.2, and cooling from a brazing temperature of 600 C. to room temperature was performed at a cooling rate of 100 C./min.

[0114] A cathode current density after brazing is affected by an element diffusion state after brazing. The element diffusion state is determined by the heat input amount if the material specifications (added components before brazing and amounts thereof) arc determined. Therefore, by specifying the heat input amount, the cathode current density of the clad material before brazing can be evaluated. The heat input amount is a parameter indicating the ease of element diffusion, and herein, is expressed as the integration of the product of the diffusion coefficient of Zn and time. The diffusion coefficient is obtained by the following formula.

[0115] Diffusion coefficient=frequency factorEXP (activation energy/(gas constanttemperature expressed in absolute temperature))

[0116] Frequency factor: 1.7710.sup.5 (m.sup.2/s)

[0117] Activation energy: 118 (kJ/mol)

[0118] Regarding the completion of the brazing, the completion of the brazing is set to the time when the temperature reaches room temperature after a heating treatment.

[0119] Moreover, brazing conditions including the heat input amount are not limited to the above conditions, and the above conditions can be used as measurement conditions for the clad material before brazing.

[0120] For each specimen in examples, the following evaluation was performed and shown in Tables 3 and 6.

[0121] Brazability

[0122] o Joint ratio

[0123] A joint ratio was obtained by the following formula, and superiority and inferiority between samples were evaluated.

[0124] Fin joint ratio=(total brazing length of fin and tube/total contact length of fin and tube)100

[0125] Regarding the joint ratio, 90% or more was evaluated as O, and less than 90% was evaluated as X

[0126] o Fillet length

[0127] A sample cut out from the core was embedded in a resin and mirror-polished, and a fillet length at a joint 13 between a fin 11 and a tube 12 was measured using an optical microscope as shown in FIG. 3. The number of joints to be measured was 20 and the average thereof was taken as the fillet length to evaluate superiority or inferiority.

[0128] In the fillet length, 600 m or more was evaluated as A, 500 m or more and less than 600 m as B, 400 m or more and less than 500 m as C, 300 m or more and less than 400 m as D, and less than 300 m as E.

[0129] o Coarse primary crystal phase Si particles

[0130] A produced brazing sheet was embedded in a resin, a cross section thereof parallel to a rolling direction was mirror-polished, and the structure thereof was revealed with Barker's solution and then observed with an optical microscope to evaluate the formation state of coarse primary phase Si in a brazing material layer. Observation was performed on a visual field of 300 m at 10 points.

[0131] A case where coarse Si particles having an equivalent circle diameter of 30 m or more were less than 2 in number was evaluated as A, a range from 2 to 9 was evaluated as B, and a case of 10 or more particles was evaluated as C.

[0132] Strength after Brazing

[0133] The brazing sheet was placed in a furnace in a drop form, and a brazing equivalent heat treatment was performed under the brazing conditions. Thereafter, the sample was cut out, a tensile test was conducted at room temperature by a normal method based on JIS, and a tensile strength was evaluated.

[0134] Regarding the strength after brazing, 160 MPa or more was evaluated as A, 150 MPa or more and less than 160 MPa as B, 140 MPa or more and less than 150 MPa as C, and less than 140 MPa as D.

[0135] Corrosion Resistance

[0136] The brazing sheet was placed in the furnace in a drop form, and the brazing equivalent heat treatment was performed under the brazing conditions. Thereafter, the sample was cut into a size of 30 mm80 mm, and immersed in a SWAAT solution for 2 days. Corrosion products were removed from the sample after the corrosion test with chromic acid phosphate, and the corrosion weight loss was calculated from the weight before and after the corrosion test.

[0137] For corrosion weight loss, less than 5 mg/cm.sup.2 was evaluated as A, 5 to 8 mg/cm.sup.2 or less as B, 8 to 10 mg/cm.sup.2 or less as less as C, and more than 10 mg/cm.sup.2 as D.

[0138] Sacrificial Anode Effect

[0139] Regarding the sacrificial anode effect, the surfaces other than the sacrificial material surface were masked and then subjected to SWAAT for 40 days. Corrosion products were removed from the sample after the corrosion test with chromic acid phosphate, and the corrosion depth was measured by observing the cross section of a maximum corrosion portion.

[0140] Regarding the corrosion depth, within half of the sheet thickness was evaluated as A, not penetrated although exceeding half the sheet thickness as B, and penetrated as C.

[0141] Cathode Current Density

[0142] The cathode current density was obtained by cutting a sample for polarization measurement from the material subjected to the brazing equivalent heat treatment under the above brazing conditions. After masking surfaces other than the measurement surface, the sample was immersed in a 30% HNO.sub.3 solution at room temperature for 5 seconds, washed with tap water or ion-exchange water, and then subjected to cathode polarization measurement as it was without being dried, under air release conditions in a 5% NaCl aqueous solution adjusted to a pH of 3 at room temperature. By setting a potential sweep rate to 0.5 mV/s, the voltage was swept to 1200 mV, and the current density at 1000 mV was defined as the cathode current density.

[0143] Mg Concentration of Surface of Brazing Material at Braze Melting Temperature The brazing equivalent heat treatment was performed under the above brazing conditions, the sample was taken out from the furnace at the moment when the braze melting temperature (a solidus temperature was calculated from the components using the phase diagram calculation software JMatPro, and a temperature subtracted by 10 C. from the solidus temperature) was reached, the sample was embedded in a resin and mirror-polished, and the Mg concentration on the surface of the brazing material was measured by EPMA analysis in a cross-sectional direction. In the measured EPMA data, the average Mg concentration in a range of 5 m from the surface of the brazing material was taken as the Mg concentration on the surface of the brazing material.

[0144] Since the braze melting temperature varies depending on the components of a material, the solidus temperature was obtained using the phase diagram calculation software (JMatPro; trademark), and the temperature subtracted by 10 C. from the solidus temperature was treated as the braze melting temperature.

TABLE-US-00001 TABLE 1 MgBi compound Elements added to brazing material [/10,000 m.sup.2] [wt %] Manufacturing Less 5 m (Bi + Specimen No. Mg Si Bi Sr Fe Mn method than 5 m or more Mg) Sr Example 1 0.02 11.0 0.15 0.0005 0.12 0.07 E 24 0 0.000085 2 0.03 11.0 0.15 0.0005 0.06 0.01 E 39 0 0.00009 3 0.1 11.0 0.15 0.0005 0.12 0.07 E 41 0 0.000125 4 0.6 11.0 0.15 0.0005 0.12 0.07 F 35 0 0.000375 5 0.8 11.0 0.23 0.007 0.12 0.07 H 44 0 0.00721 6 1.2 11.0 0.20 0.007 0.09 0.04 H 48 0 0.0098 7 1.5 11.0 0.20 0.007 0.06 0.01 H 55 0 0.0119 8 0.5 6.0 0.23 0.008 0.12 0.07 I 54 0 0.00584 9 0.3 6.5 0.20 0.007 0.15 0.1 B 34 0 0.0035 10 0.3 13.0 0.10 0.005 0.12 0.07 E 38 0 0.002 11 0.5 14.0 0.20 0.005 0.12 0.3 G 55 1 0.0035 12 0.3 11.0 0.05 0.005 0.12 0.2 I 32 0 0.00175 13 0.5 11.0 0.08 0.008 0.12 0.07 F 33 0 0.00464 14 0.5 12.0 0.23 0.006 0.15 0.1 A 40 0 0.00438 15 0.5 11.0 0.25 0.006 0.15 0.1 B 46 0 0.0045 16 0.5 10.0 0.15 0.0001 0.15 0.1 E 38 0 0.000065 17 0.5 11.0 0.15 0.0005 0.15 0.1 F 31 0 0.000325 18 0.2 10.0 0.15 0.06 0.12 0.07 I 33 0 0.021 19 0.05 10.0 0.15 0.09 0.12 0.07 E 24 0 0.018 20 0.1 10.0 0.15 0.1 0.12 0.07 E 35 0 0.025 21 1.2 11.0 0.20 0.07 0.07 0.02 H 49 0 0.098 22 1.2 11.0 0.20 0.05 0.12 0.07 H 49 0 0.07 23 0.5 11.0 0.15 0.0005 0.05 0.1 E 38 0 0.000325 24 0.5 11.0 0.15 0.0005 0.10 0.1 E 38 0 0.000325 25 0.5 11.0 0.15 0.0005 0.20 0.1 E 38 0 0.000325 26 0.5 11.0 0.15 0.0005 0.30 0.2 E 38 0 0.000325 27 0.5 11.0 0.15 0.008 0.12 0.07 E 37 0 0.0052 28 0.5 9.5 0.20 0.006 0.12 0.07 A 38 0 0.0042 29 0.5 10.0 0.20 0.007 0.12 0.07 D 43 0 0.0049 30 0.5 10.0 0.20 0.008 0.12 0.07 B 33 0 0.0056 31 0.5 6.0 0.23 0.008 0.12 0.07 I 54 0 0.00584 32 0.3 6.5 0.20 0.007 0.15 0.1 B 34 0 0.0035 33 0.3 13.0 0.10 0.005 0.12 0.07 E 38 0 0.002 34 0.5 14.0 0.20 0.005 0.06 0.01 G 55 1 0.0035 35 0.3 11.0 0.05 0.005 0.12 0.07 I 32 0 0.00175 36 0.5 10.0 0.20 0.01 0.12 0.07 F 47 0 0.007 37 0.5 11.0 0.20 0.01 0.17 0.12 B 33 0 0.007 38 0.5 9.5 0.20 0.009 0.12 0.07 J 66 1 0.0063 39 0.3 11.0 0.20 0.01 0.12 0.07 A 41 0 0.005 40 0.3 9.5 0.20 0.01 0.12 0.07 B 36 0 0.005 41 0.3 11.0 0.20 0.004 0.12 0.07 I 55 0 0.002 42 0.3 8.0 0.15 0.007 0.12 0.07 E 41 0 0.00315 43 0.3 11.0 0.15 0.005 0.12 0.07 G 33 0 0.00225 44 0.3 11.5 0.15 0.01 0.12 0.07 J 47 0 0.0045 45 0.5 11.0 0.15 0.01 0.17 0.12 I 35 0 0.0065 46 0.5 8.0 0.20 0.01 0.12 0.07 C 38 0 0.007 47 0.5 11.0 0.20 0.01 0.12 0.07 C 38 0 0.007 48 0.3 8.8 0.20 0.01 0.12 0.07 B 36 0 0.005 49 0.5 11.0 0.15 0.008 0.12 0.07 E 37 0 0.0052 50 0.5 9.5 0.20 0.006 0.12 0.07 A 38 0 0.0042 51 0.5 10.0 0.20 0.007 0.12 0.07 D 43 0 0.0049 52 0.3 13.0 0.10 0.005 0.12 0.07 E 38 0 0.002 53 0.5 14.0 0.20 0.005 0.12 0.07 G 55 1 0.0035 54 0.3 11.0 0.20 0.004 0.12 0.07 I 55 0 0.002 55 0.3 11.0 0.15 0.007 0.12 0.07 E 41 0 0.00315 56 0.3 10.0 0.15 0.005 0.12 0.07 G 33 0 0.00225 57 0.5 11.0 0.20 0.008 0.17 0.12 D 44 0 0.0056 58 0.5 8.5 0.15 0.01 0.12 0.07 I 38 0 0.0065 59 0.5 11.0 0.15 0.009 0.12 0.07 J 42 0 0.00585 60 0.5 9.2 0.20 0.01 0.12 0.07 H 43 0 0.007 61 0.5 11.0 0.20 0.006 0.12 0.07 A 41 0 0.0042 62 0.5 9.0 0.20 0.0002 0.12 0.07 J 66 1 0.00014 63 0.5 11.0 0.23 0.01 0.12 0.07 B 47 0 0.0073 64 0.5 8.0 0.12 0.01 0.09 0.04 F 33 0 0.0062 65 0.5 11.0 0.20 0.008 0.12 0.07 B 34 0 0.0056 66 0.5 11.0 0.15 0.01 0.12 0.07 G 36 0 0.0065 67 0.3 11.0 0.20 0.02 0.12 0.07 E 35 0 0.01 68 0.5 11.0 0.15 0.0005 0.15 0.1 F 31 0 0.000325 69 0.5 9.5 0.15 0.0005 0.25 0.2 F 31 0 0.000325 70 1.0 8.0 0.12 0.0005 0.10 0.05 F 31 0 0.00056 71 1.2 13.0 0.15 0.0005 0.07 0.02 F 31 0 0.000675 72 0.3 11.0 0.23 0.0005 0.10 0.05 F 31 0 0.000265

TABLE-US-00002 TABLE 2 Core material composition [wt %] Specimen No. Si Mg Mn Cu Fe Zn Example 1 0.7 0.3 1.2 0.01 0.2 0.9 2 0.7 0.3 1.2 0.01 0.2 0.9 3 0.7 0.3 1.2 0.05 0.2 0.7 4 0.7 0.3 1.5 0.05 0.2 0.6 5 0.7 0.3 1.5 0.2 0.6 6 0.7 0.3 1.5 0.2 0.6 7 0.7 0.3 1.5 0.2 0.6 8 0.04 0.5 1.5 0.02 0.2 0.9 9 0.1 0.5 1.5 0.05 0.2 0.9 10 0.1 0.5 1.5 0.05 0.2 0.7 11 0.07 0.5 1.5 0.05 0.2 0.7 12 0.7 0.5 1.2 0.005 0.2 0.9 13 0.7 0.5 1.2 0.05 0.2 0.9 14 0.7 0.5 1.2 0.01 0.2 0.9 15 0.7 0.5 1.2 0.03 0.2 0.9 16 0.7 0.5 1.2 0.05 0.2 1.1 17 0.05 0.5 1.5 0.05 0.2 0.9 18 0.7 0.5 1.5 0.01 0.2 1.2 19 0.7 0.5 1.5 0.05 0.2 0.9 20 0.7 0.5 1.5 0.05 0.2 0.9 21 0.7 0.5 1.5 0.05 0.2 0.9 22 0.7 0.5 1.5 0.05 0.2 0.9 23 0.7 0.5 1.2 0.05 0.2 1.1 24 0.7 0.5 1.2 0.05 0.2 1.1 25 0.7 0.5 1.2 0.05 0.2 1.1 26 0.7 0.5 1.2 0.05 0.2 1.1 27 0.01 0.5 1.2 0.05 0.2 0.7 28 0.05 0.5 1.2 0.05 0.2 0.7 29 0.8 0.5 1.2 0.05 0.2 0.5 30 1.0 0.5 1.2 0.04 0.2 0.5 31 0.04 1.5 0.02 0.2 0.9 32 0.1 0.01 1.5 0.05 0.2 0.9 33 0.1 0.02 1.5 0.05 0.2 0.7 34 0.07 1.5 0.05 0.2 0.7 35 0.7 0.04 1.2 0.005 0.2 0.9 36 0.75 0.1 1.2 0.05 0.2 0.9 37 0.75 0.2 1.2 0.008 0.2 0.9 38 0.75 0.65 1.2 0.05 0.2 0.9 39 0.75 0.7 1.2 0.05 0.2 0.9 40 0.7 0.5 0.8 0.05 0.2 0.6 41 0.7 0.5 1.0 0.05 0.2 0.7 42 0.7 0.5 1.7 0.05 0.2 0.6 43 0.7 0.5 1.8 0.05 0.2 0.6 44 0.85 0.5 1.2 0.005 0.2 0.6 45 0.85 0.5 1.2 0.01 0.2 1.3 46 0.85 0.5 1.4 0.2 0.2 0.9 47 0.2 0.5 1.2 0.3 0.2 0.9 48 0.7 0.5 1.2 0.05 0.2 49 0.02 0.5 1.2 0.05 0.2 0.01 50 0.1 0.5 1.2 0.05 0.2 0 51 0.8 0.5 1.2 0.05 0.2 0.02 52 0.1 0.5 1.5 0.05 0.2 53 0.07 0.5 1.5 0.05 0.2 0.05 54 0.7 0.5 1.2 0.05 0.2 0.2 55 0.4 0.5 1.4 0.05 0.2 1.3 56 0.3 0.5 1.4 0.05 0.2 1.6 57 0.5 0.5 1.2 0.02 0.1 0.9 58 0.5 0.5 1.4 0.03 0.12 0.9 59 0.5 0.5 1.4 0.05 0.4 0.9 60 0.5 0.5 1.4 0.05 0.5 0.9 61 0.2 0.5 1.4 0.05 0.2 0.7 62 0.7 0.5 1.2 0.01 0.2 1.2 63 0.7 0.5 1.3 0.05 0.2 0.6 64 0.4 0.5 1.4 0.007 0.2 1.2 65 0.07 0.5 1.5 0.05 0.2 0.9 66 0.7 0.5 1.2 0.05 0.2 0.9 67 0.7 0.2 1.4 0.05 0.2 0.5 68 0.05 0.5 1.5 0.05 0.2 0.9 69 0.05 0.5 1.5 0.05 0.2 0.9 70 0.05 0.5 1.5 0.05 0.2 0.9 71 0.05 0.5 1.5 0.05 0.2 0.9 72 0.05 0.5 1.5 0.05 0.2 0.9

TABLE-US-00003 TABLE 3 Concentration of Mg on surface of Corrosion resistance brazing Brazability Cathode Corrosion Sacrificial Strength after material Joint Fillet Coarse Si current weight Anode brazing Specimen No. (wt %) ratio length particles density loss Effect [MPa] Evaluation Example 1 0.14 D A 0.06 A A 148 C 2 0.18 C A 0.06 A A 148 C 3 0.25 B A 0.08 A A 148 C 4 0.44 A A 0.08 A A 158 B 5 0.54 B A 0.08 A A 160 A 6 0.73 C A 0.08 A A 162 A 7 0.86 D A 0.08 A A 165 A 8 0.5 C A 0.06 A A 161 A 9 0.4 B A 0.06 A A 160 A 10 0.4 B A 0.09 B A 160 A 11 0.5 C B 0.1 C A 162 A 12 0.4 C A 0.08 A A 160 A 13 0.5 B A 0.08 A A 162 A 14 0.5 A A 0.08 A A 162 A 15 0.5 C A 0.08 A A 161 A 16 0.5 A B 0.08 A A 162 A 17 0.5 A A 0.08 A A 161 A 18 0.36 B A 0.08 B A 164 A 19 0.07 D B 0.08 A A 163 A 20 0.32 B B 0.08 A A 163 A 21 0.84 C B 0.08 A A 174 A 22 0.84 C A 0.08 A A 174 A 23 0.5 A B 0.04 A A 149 C 24 0.5 A B 0.05 A A 155 B 25 0.5 A B 0.08 B A 162 A 26 0.5 A B 0.1 C A 162 A 27 0.5 A A 0.08 A A 157 B 28 0.5 A A 0.08 A A 160 A 29 0.5 A A 0.08 A A 163 A 30 0.5 C A 0.08 A A 164 A 31 0.24 C A 0.06 A A 161 A 32 0.14 C A 0.06 A A 140 C 33 0.14 C A 0.09 B A 141 C 34 0.23 C B 0.08 B A 140 C 35 0.15 D A 0.08 A A 160 A 36 0.29 A A 0.08 A A 143 C 37 0.34 B A 0.08 A A 148 C 38 0.58 A A 0.08 A A 169 A 39 0.48 B A 0.08 A A 170 A 40 0.4 B A 0.08 A A 157 B 41 0.4 A A 0.08 A A 160 A 42 0.4 B A 0.08 A A 168 A 43 0.4 B A 0.08 A A 169 A 44 0.4 A A 0.08 A A 159 B 45 0.5 A A 0.08 A A 161 A 46 0.5 A A 0.08 A A 172 A 47 0.5 A A 0.08 B A 168 A 48 0.4 B A 0.08 A B 160 A 49 0.5 A A 0.08 A B 156 B 50 0.5 A A 0.08 A B 157 B 51 0.5 A A 0.08 A B 163 A 52 0.4 B A 0.09 A B 160 A 53 0.5 C B 0.1 B B 162 A 54 0.4 A A 0.08 A A 160 A 55 0.4 B A 0.08 B A 161 A 56 0.4 B A 0.08 C A 160 A 57 0.5 A A 0.08 A A 159 B 58 0.5 A A 0.08 A A 163 A 59 0.5 A A 0.08 A A 165 A 60 0.5 A A 0.08 B A 166 A 61 0.5 B A 0.08 A A 161 A 62 0.5 A A 0.08 B A 162 A 63 0.5 A A 0.08 A A 163 A 64 0.5 B A 0.08 B A 163 A 65 0.5 A A 0.08 A A 162 A 66 0.5 B A 0.08 A A 162 A 67 0.25 B A 0.08 A A 149 C 68 0.5 A A 0.08 A A 161 A 69 0.5 B A 0.08 A A 161 A 70 0.74 C A 0.08 A A 166 A 71 0.83 B A 0.08 A A 168 A 72 0.41 B A 0.08 A A 160 A

TABLE-US-00004 TABLE 4 MgBi compound Elements added to brazing material [/10,000 m.sup.2] [wt %] Manufacturing Less 5 m (Bi + Specimen No. Mg Si Bi Sr Fe Mn method than 5 m or more Mg) Sr Comparative 1 0.01 11.0 0.11 0.0005 0.17 0.12 B 10 0 0.00006 Example 2 1.6 11.0 0.15 0.0005 0.06 0.01 E 32 0 0.000875 3 0.5 5.5 0.23 0.01 0.17 0.12 A 42 0 0.0073 4 0.3 14.5 0.20 0.008 0.11 0.06 I 55 1 0.004 5 0.1 11.0 0.04 0.0005 0.17 0.12 C 15 0 0.00007 6 0.5 8.0 0.28 0.01 0.17 0.12 C 45 1 0.0078 7 0.5 11.0 0.15 0.00008 0.17 0.12 C 42 0 0.000052 8 0.5 9.0 0.15 0.13 0.17 0.12 C 0.0845 9 0.5 11.0 0.15 0.0005 0.03 0.04 E 38 0 0.000325 10 0.5 11.0 0.15 0.0005 0.4 0.20 E 38 0 0.000325 11 0.5 9.0 0.15 0.01 0.17 0.12 G 33 0 0.0065 12 0.5 9.0 0.15 0.005 0.17 0.12 I 36 0 0.00325 13 0.5 10.0 0.20 0.01 0.15 0.10 B 0.007 14 0.5 11.0 0.20 0.008 0.12 0.07 C 37 0 0.0056 15 0.5 10.0 0.20 0.006 0.17 0.12 C 0.0042 16 0.3 11.0 0.20 0.01 0.17 0.12 A 42 0 0.005 17 0.3 11.0 0.20 0.005 0.17 0.12 D 45 0 0.0025 18 0.3 10.5 0.20 0.01 0.13 0.08 B 0.005 19 1.2 9.5 0.20 0.08 0.17 0.12 B 0.112 20 1.5 11.0 0.20 0.06 0.17 0.12 B 0.102 21 0.3 10.0 0.15 0.01 0.15 0.10 K 12 3 0.0045 22 0.3 11.0 0.15 0.007 0.17 0.12 N 17 5 0.00315 23 0.5 11.0 0.20 0.007 0.17 0.12 O 16 4 0.0049 24 0.5 9.0 0.20 0.01 0.17 0.12 L 15 7 0.007 25 0.5 9.0 0.15 0.008 0.2 0.15 M 15 6 0.0052 26 0.5 11.0 0.15 0.01 0.17 0.12 K 13 5 0.0065 27 0.5 10.5 0.12 0.006 0.17 0.12 N 18 3 0.00372 28 0.01 11.0 0.15 0.0005 0.17 0.12 E 39 0 0.00008 29 0.5 14.0 0.20 0.005 0.3 0.25 G 55 1 0.0035 30 1.5 12.0 0.20 0.007 0.2 0.19 H 55 0 0.0119

TABLE-US-00005 TABLE 5 Core material composition [wt %] Specimen No. Si Mg Mn Cu Fe Zn Comparative 1 0.7 0.2 1.2 0.05 0.2 0.5 Example 2 0.7 0.5 1.2 0.05 0.2 0.5 3 0.7 0.5 1.2 0.05 0.2 0.5 4 0.7 0.5 1.1 0.05 0.2 0.5 5 0.7 0.5 1.2 0.01 0.2 0.5 6 0.7 0.5 1.2 0.05 0.2 0.9 7 0.7 0.5 1.2 0.05 0.2 0.9 8 0.7 0.5 1.2 0.05 0.2 0.6 9 0.7 0.5 1.2 0.05 0.2 1.1 10 0.7 0.5 1.2 0.05 0.2 1.1 11 0.005 0.5 1.2 0.05 0.2 0.6 12 1.2 0.5 1.2 0.02 0.2 0.6 13 0.7 0.75 1.2 0.05 0.2 0.6 14 0.7 0.2 0.7 0.05 0.2 0.8 15 0.7 0.2 1.9 0.05 0.2 0.9 16 0.1 0.3 1.4 0.35 0.2 0.9 17 0.5 0.3 1.2 0.05 0.05 0.9 18 0.5 0.3 1.4 0.05 0.7 0.9 19 0.7 0.5 1.3 0.05 0.2 0.9 20 0.7 0.5 1.3 0.05 0.2 0.9 21 0.4 0.5 1.4 0.05 0.2 0.8 22 0.4 0.5 1.4 0.03 0.2 0.8 23 0.7 0.5 1.2 0.05 0.2 0.9 24 0.7 0.5 1.2 0.05 0.2 1.1 25 0.7 0.5 1.2 0.05 0.2 0.9 26 0.7 0.5 1.2 0.04 0.2 0.9 27 0.7 0.5 1.3 0.05 0.2 1.1 28 0.7 0.15 1.1 0.05 0.2 0.9 29 0.07 0.5 1.5 0.05 0.2 0.7 30 0.7 0.3 1.5 0.0006 0.2 0.6

TABLE-US-00006 TABLE 6 Concentration of Mg on surface of Corrosion resistance brazing Brazability Cathode Corrosion Sacrificial Strength after material Joint Fillet Coarse Si current weight Anode brazing Specimen No. (wt %) ratio length particles density loss Effect [MPa] Evaluation Comparative 1 0.1 X E A 0.08 B A 143 C Example 2 1.05 X E A 0.09 A A 161 A 3 0.5 E A 0.08 A A 162 A 4 0.4 X E C 0.09 C A 158 B 5 0.17 E A 0.08 B A 159 B 6 0.5 X E A 0.08 A A 162 A 7 0.5 X E C 0.08 A A 165 A 8 Evaluation material cannot be manufactured and evaluated. 9 Not good since base metal cost is too expensive 10 0.5 A B 0.2 D A 162 A 11 Not good since base metal cost is too expensive 12 0.5 Poor brazing due to generation 0.08 A A 190 A of significant erosion 13 Evaluation material cannot be manufactured and evaluated. 14 0.5 A A 0.08 A A 139 D 15 Evaluation material cannot be manufactured and evaluated. 16 0.3 B A 0.08 D A 161 B 17 Not good since base metal cost is too expensive 18 Evaluation material cannot be manufactured and evaluated. 19 Evaluation material cannot be manufactured and evaluated. 20 Evaluation material cannot be manufactured and evaluated. 21 0.4 E A 0.08 B A 161 A 22 0.4 E A 0.08 B A 161 A 23 0.5 E A 0.08 B A 162 A 24 0.5 E A 0.08 B A 162 A 25 0.5 E A 0.08 B A 162 A 26 0.5 E A 0.08 B A 162 A 27 0.5 E A 0.08 B A 163 A 28 0.08 X E A 0.08 A A 139 D 29 0.5 C B 0.13 E A 162 A 30 0.86 D A 0.11 E A 165 A

TABLE-US-00007 TABLE 7 (Brazing material) Casting condition Homogenization Hot rolling condition Molten condition Rolling time metal Temperature between 400 C. Equivalent Finish Cooling temperature and time and 500 C. strain temperature rate Specimen No. ( C.) ( C., h) (min) ( C.) ( C./h) Target A 710 450 C., 5 h 15 5.7 320 25 range B 715 450 C., 5 h 14 5.4 334 21 C 715 500 C., 2 h 10 5.5 355 35 D 725 550 C., 2 h 14 5.5 274 28 E 725 400 C., 8 h 18 5.9 290 38 F 735 400 C., 8 h 22 5.7 252 35 G 735 450 C., 8 h 15 6.1 315 42 H 720 450 C., 8 h 24 5 340 34 I 755 500 C., 5 h 14 6.4 347 52 J 745 500 C., 5 h 30 5 290 32 Outside K 695 400 C., 8 h 15 5.3 267 18 the L 680 380 C., 8 h 8 5.2 220 12 target M 715 380 C., 8 h 22 4.8 337 36 N 670 350 C., 8 h 15 4.6 395 22 O 705 350 C. 8 h 7 5.7 322 35

[0145] While preferred embodiments of the invention have been described and illustrated above, it should be understood that these are exemplary of the invention and are not to be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit or scope of the present invention. Accordingly, the invention is not to be considered as being limited by the foregoing description, and is only limited by the scope of the appended claims.

REFERENCE SIGNS LIST

[0146] 1: Aluminum alloy clad material

[0147] 2: Aluminum alloy core material

[0148] 3A: Aluminum alloy brazing material

[0149] 3B: Aluminum alloy brazing material

[0150] 5: Aluminum heat exchanger

[0151] 6: Fin

[0152] 7: Tube

[0153] 10: Other components

[0154] 11: Fin

[0155] 12: Tube

[0156] 13: Joint