JPH09241783A - Aluminum alloy sheet for noncorrosive flux brazing and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve formability and brazability by specifying a composition of elements. SOLUTION: The Al alloy sheet has a composition consisting of, by weight, 0.4-1.6% Si, 0.4-1.0% Cu, 0.05-0.3% Ti, and the balance Al with <=0.2% Mg as impurity. In the case where a part of this sheet is alloyed with metal and melted and forms a brazing filler metal, characteristics, such as increased amount of brazing filler metal at brazing, excellent fluidity of brazing filler metal, and improved strength and corrosion resistance after brazing, can be obtained. Further, in the case of a sheet with the composition, where the average size of recrystallized grains is regulated to <=70μm and a strain of 1-5% is introduced, formability is improved and, further, the average size of recrystallized grains becomes >=100μm in the course of brazing. As a result, at the time of brazing, the amount of brazing filler metal is increased and the fluidity of brazing filler metal is improved and a sufficient fillet is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a product to be assembled and brazed after forming, for example, a laminated evaporator for a heat exchanger and a laminated base plate forming a fluid passage of a laminated oil cooler, and a header plate for a radiator. Aluminum alloy plate, etc. used for, etc., excellent in formability, a large amount of braze is formed during brazing, good fluidity of braze, and strength and corrosion resistance after brazing. TECHNICAL FIELD The present invention relates to an aluminum alloy plate which partially forms a brazing filler metal by alloying with a metal by using a non-corrosive flux having excellent properties, and a method for producing the plate.

[0002]

2. Description of the Related Art A heat exchanger of the Dron cup type is disclosed in, for example, Japanese Patent Application Laid-Open No. Sho 61-79752, and has a bulging portion or a drawing portion.
It is manufactured in such a manner that a pair of material plates form a pipe as a refrigerant flow section, which is juxtaposed, and a braided fin for promoting heat exchange is brazed to the refrigerant flow section. However, the brazing of such a heat exchanger has a corrosion-resistant and high-strength core material made of an Al-Mn-based alloy represented by 3003,
A so-called brazing sheet clad with a skin material made of an Al-Si alloy is used.

However, as a method for producing the brazing sheet as described above, a cast alloy obtained by casting a molten alloy which is a core material is homogenized, and a skin material alloy which is a brazing filler metal separately from the cast alloy. It is common practice to combine a plate obtained by rolling an ingot, hot cold-roll it into a plate having a predetermined thickness, and then finally anneal it into an O material. In order to improve the formability of the obtained sheet, the homogenization treatment conditions in the above manufacturing process are set to high temperature and long time, and the crystal grain size of the sheet after the final annealing treatment is made fine. The brazing described above includes a method of using a flux or brazing in a vacuum or an inert gas atmosphere. For example, when Al-6-12% Si alloy is used as a brazing sheet skin material, Usually, the brazing is performed by heating and holding at a temperature of about 600 ° C. for about 2 to 3 minutes.

By the way, as described above, when the crystal grain structure is fine, there is a drawback that the crystal grain boundary diffusion of Si from the brazing material easily occurs during the brazing process and the fluidity of the brazing material is lowered. As a countermeasure against this, the rate of temperature rise to the final annealing temperature is set to rapid heating, and a slight strain is applied to the clad material that has been subjected to such a treatment to produce coarse recrystallized grains in the brazing process, resulting in grain boundaries of Si. A method for producing a clad material that prevents diffusion as much as possible and prevents deterioration of the fluidity of the braze has been proposed (Japanese Patent Publication No. 6-47196), but brazing products using this clad material are It has the drawback of being expensive to manufacture.

Therefore, in recent years, there have been some proposals for brazing without using the above-mentioned clad material, and one of such methods is a non-corrosive fluoride flux of potassium aluminum fluoride system. Brazing with a mixture of metallic silicon powders is disclosed in US Pat.
It was published in issue 5100048. That is, according to this method, the silicon applied to the surface of the aluminum material rapidly diffuses into the aluminum material at the brazing temperature, and melts when the surface layer of the aluminum material approaches the Al-Si eutectic composition (eutectic temperature: 577).
C.), and the components are joined together by soldering.

That is, specifically, a mixture of a fluoride-based flux and metallic silicon powder is applied by being suspended in dry powder or a volatile liquid such as water or alcohol, and the mixture is mixed in a weight ratio of 0.1-0.1. About 3: 1 and the mixture coating amount is 5
To 30 g / m ^2, the brazing temperature is 577 ° C. or higher, but the time is 2-5 minutes, a mixture of about 30% silicon 20 to 30 g / m ² was applied as the optimum condition, the material for with Mataro A pure Al material and an Al-1% Mn material are shown as.

[0007]

The brazing method using a mixture of a non-corrosive fluoride-based flux and metallic silicon powder can reduce the cost, but if it is directly applied to the conventional 1000 series or 3000 series alloys, it will form. It became clear that the fillet formed becomes smaller than that of the brazing sheet, and if the gap between the members at the time of assembling the heat exchanger is large, defective bonding occurs. However, in order to prevent this, the gap between the members should be made as small as possible, and the coating amount of the mixture of the flux and metallic silicon powder should be increased. There is a limit due to the relationship. On the other hand, in addition to the high cost, there is an increased risk that local dissolution of the member becomes large at the place where a large amount of silicon powder adheres, which is inevitable when the mixture is applied to the molded member. To do.

Regarding the method of manufacturing the material, the method of forming a coarse recrystallized grain structure in the brazing process by applying a slight strain after annealing the O material by the rapid acceleration described above is excellent in both formability and brazing property. Although it is a manufacturing method, on the other hand, the strength after brazing is reduced due to the formation of coarse crystal grains, and in recent years, there has been a need to reduce the thickness of members in response to the demand for smaller and lighter heat exchangers.
It has become difficult to apply this manufacturing method to 3,000 series and 3000 series alloys represented by 3003. Further, not only the strength but also the corrosion resistance is important for making the member thinner.

[0009]

Means for Solving the Problems The inventors of the present invention have made extensive studies in order to solve such drawbacks, and as a result, an aluminum plate containing a specific amount of Si, Cu and Ti at the same time and comprising the balance impurities, When a part of this plate is alloyed with a metal and melted to form a brazing filler metal,
When brazing, it was found that the amount of braze is large, the fluidity of the braze is good, and the strength and corrosion resistance after brazing are excellent, and in such a composition, the average grain size of recrystallized grains is The plate having a thickness of 70 μm or less and a strain of 1 to 5% introduced therein has good formability and has an average recrystallized grain size of 100 μm or more in the brazing process, and a large amount of brazing during brazing, The inventors have completed an advantageous method by finding that the fluidity of katsura wax is good, and are as follows.

(1) Partly alloys with a metal and melts,
A material for forming a brazing filler metal, and in wt%, Si: 0.4 to 1.6%, Cu: 0.4 to 1.0%, Ti: 0.05 to 0.
An aluminum alloy plate for non-corrosive flux brazing, characterized in that it contains 3%, the balance is Al and unavoidable impurities, and the content of Mg as impurities is 0.2% or less.

(2) Partly alloys with metal and melts,
A material for forming a brazing filler metal, and in wt%, Si: 0.4 to 1.6%, Cu: 0.4 to 1.0%, Ti: 0.05 to 0.
3%, Mn: 0.3-0.8%, balance Al and unavoidable impurities, and Mg as an impurity is 0.2% or less, for non-corrosive flux brazing Aluminum alloy plate.

(3) The composition according to any one of the items (1) and (2), wherein the recrystallized grains have an average grain size of 70 μm or less and a strain of 1 to 5% is introduced. Aluminum alloy plate for non-corrosive flux brazing, which is characterized in that

(4) Partly alloys with metal and melts,
A material for forming a brazing filler metal, which is an aluminum alloy ingot having the composition described in the item (1), is 400 to 620 ° C.
After homogenizing by holding at a temperature of 1 to 15 hours, hot rolling and cold rolling are performed to obtain a plate having a predetermined thickness, and the plate is held at a temperature of 280 ° C. or higher for a holding time of 5 hours or less to finally finish. Manufacture of an aluminum alloy plate for non-corrosive flux brazing, characterized by performing an annealing treatment to reduce the average grain size of recrystallized grains to 70 μm or less, and then subjecting this plate to a strain introduction process of 1 to 5%. Method.

(5) Partly alloys with the metal and melts,
A material for forming a brazing material, which is obtained by holding an aluminum alloy ingot having the composition described in (2) above at a temperature of 530 to 620 ° C. for 1 to 15 hours for homogenization treatment, and then hot rolling and cooling. Hot rolled into a plate with a specified thickness,
The final annealing treatment is performed at a temperature rising rate of 320 ° C./min or more and at a temperature of 320 ° C. or more for a holding time of 10 minutes or less to make the average grain size of the recrystallized grains 70 μm or less.
A method for producing an aluminum alloy plate for non-corrosive flux brazing, which comprises performing a 5% strain introduction process.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The non-corrosive flux used in the present invention is a powder mixture of fluorides such as LiF, NaF, KF, CaF ₂ , AlF ₃ and SiF ₄ , or a powder obtained by melting these powders, or the above Complex compounds of fluorides such as KAlF ₄ , K ₂ AlF ₅
(K ₂ AlF ₅ · H ₂ O), K ₃ AlF ₆ , K ₂ SiF ₆ or the like, or a mixture of these or powdered after melting,
None of such fluoride-based fluxes has corrosiveness to aluminum as chlorides do. The average particle size of this powder is 0.1 to 30 μm.
It is preferably 1 to 10 μm on average.

As a metal that forms a braze by alloying with a plate material and melting, there is a silicon-zinc alloy containing 10 to 30% Zn in addition to silicon. Such a metal may be formed as a brazed member, for example, may be sprayed on the surface of the base plate of the heat exchanger, or may be made into a powder, and this powder is applied to the brazed member or mixed with the flux powder. May be applied as a slurry. In this case, in addition to silicon powder, 1-30
% Zinc powder or 2 to 20% copper powder may be added and mixed for coating. Particularly, alloying silicon to be supplied to the brazed member in advance has a disadvantage that the cost is high, and thermal spraying is a thermal spraying material, and there is a disadvantage due to thermal spraying. It is applied to and used.

The coating method of the above mixture is as follows.
There is a method such as the one described above, and as the slurry, one obtained by suspending the mixture in water, alcohol, or a solvent, to which a binder (acrylic resin or the like) for improving adhesion is added, or a surfactant is added. Used. After assembling the molded member into the heat exchanger, dip it in slurry or spray coating (slurry flows inside) Molded member is dipped in slurry or spray coated, electrostatic as powder Coating, thermal spraying (afterwards, assembled in heat exchanger) Plate material is immersed in slurry, or spray coating, roller coating, thermal spraying as powder (after that, it is molded into members and assembled in heat exchanger)

The alloy composition in the present invention will be described below in terms of wt% (hereinafter, simply referred to as%). Si: 0.4 to 1.6% Si increases the amount of wax forming the fillet, and
It has the effect of increasing the strength after brazing, and in the method according to the present invention, the reaction between the metallic silicon and the surface layer of the aluminum alloy member produces an Al-Si eutectic composition melt (brazing) to perform brazing. However, since Si in the aluminum alloy also becomes a part of the braze and Si has a function of reducing local melting (Japanese Patent Laid-Open No. 7-303982), when the produced braze moves to the joint. The resistance of the fillet is reduced and the amount of wax that forms the fillet is increased. That is, such Si content
If it is less than 0.4%, the above effects are small, and 1.
If it exceeds 6%, burning may occur at the brazing temperature.

Cu: 0.4 to 1.0% Cu has the effect of increasing the stored energy during strain introduction processing and facilitating recrystallization during the brazing process. It is effective in reducing the amount (when the amount of strain is large, the moldability decreases). In addition, in order to increase the strength after brazing and to make the potential of the member noble, when combined with an aluminum alloy fin having a lower potential,
It has the effect of increasing the corrosion resistance of the member. Such Cu content is 0.
If it is less than 4%, the effect is small, and if it exceeds 1.0%, the strength becomes too high and the molding processability deteriorates.

Ti: 0.05 to 0.3% Ti is unevenly distributed inside the crystal grains at the time of casting, and has the function of layering the structure of the member subjected to rolling to enhance the corrosion resistance.
When the Ti content is less than 0.05%, such an effect is poor,
On the other hand, if it exceeds 0.3%, a huge intermetallic compound is formed and the moldability is deteriorated.

Mg: Regulated to 0.2% or less Mg enhances the strength after brazing even with a small amount, but when brazing with a non-corrosive flux of aluminum potassium fluoride, flux components F and Mg are used. Reacts, the effect of the flux is reduced and the brazing property is significantly reduced.
Therefore, it is regulated to less than 0.2%.

Further, in the present invention, the effect of increasing the strength after brazing can be obtained by adding 0.3 to 0.8% of Mn. If the Mn is less than 0.3%, such an effect is poor, while if it exceeds 0.8%, the brazing property deteriorates.
Further, the amount of strain applied after annealing the O material increases, and the formability decreases.

The elements according to the present invention can accept other elements such as Fe up to 0.7%, Cr up to 0.3%, and Zn as impurity elements.

The alloy ingot having the composition described in the above (1) is 1 to 1 at a temperature of 400 to 620 ° C. after chamfering.
Hold for 15 hours and homogenize. This homogenizing treatment facilitates the subsequent rolling process, and in addition to heating to a temperature of 280 ° C. or higher for 5 hours in the final annealing treatment, a huge and flat recrystallization is performed in the heating process of the brazing process. Grains are used to substantially prevent the diffusion of Si from the brazing filler metal, and their effect is poor at less than 400 ° C or less than 1 hour, and burning is unfavorable at more than 620 ° C. However, holding for more than 15 hours is not economical because further effects cannot be expected so much and energy loss occurs. In any case, the ingot subjected to the homogenization treatment under the above conditions is subjected to hot rolling and cold rolling as appropriate to obtain a desired plate thickness.

The plate rolled to the desired thickness as described above is heated to a temperature of 280 ° C. or higher and finally annealed, and then strain-introduced, which is the average of recrystallization. Fine grain size and large recrystallized grains are obtained by formability and subsequent brazing treatment to give brazing amount and fluidity. Recrystallization cannot be completed below 280 ° C. Moldability will be inferior. The holding time of 5 hours or less includes the treatment of cooling immediately after reaching the final annealing treatment temperature. The upper limit of the final annealing temperature is 620 at which burning occurs.
Approximately ℃ is a standard.

The plate having an average grain size of recrystallization of 70 μm or less is subjected to strain introduction processing. However, the strain-introducing work applied after this final annealing is 1% or more in the present invention, whereby the core material has an average particle size of 100 μm in the heating process of the subsequent brazing step (up to a temperature of 550 ° C. for 10 to 60 minutes). The above huge and flat recrystallized grains are formed. In other words, when a part of the plate is alloyed with Si and melted to form a brazing filler metal, such coarse and flat recrystallized grains reduce the grain boundary area per unit volume, thus It is clear that the number of diffusion paths in the plane direction of Si from the brazing filler metal using the boundary as a diffusion path is very small, and Si diffusion in the plate thickness direction is effectively prevented.

Further, since the brazing material formed and melted has excellent fluidity, it flows into the brazing portion to form a sound brazing portion. The strain introduction processing described above is to give a required amount of plate thickness reduction to the brazing sheet in the present invention, and can be carried out using equipment such as a tension leveler, a stretcher, a skin pass rolling or a roller leveler. The plate thickness before the introduction processing is t ₀
And when the plate thickness after strain introduction processing is t, (t ₀ −
t) / t ₀ × 100 (%).

If the strain introduction amount is less than 1%,
Even if the preferable final annealing treatment is performed, huge and flat recrystallized grains cannot be obtained in the heating process of brazing, and the penetration of Si content during brazing must be insufficient. On the other hand, if the amount of introduced strain exceeds 5%, the elongation as a plate decreases and the Erichsen value decreases, resulting in poor moldability.

On the other hand, the alloy ingot having the composition as described in (2) above is homogenized by holding it at a temperature of 530 to 620 ° C. for 1 to 15 hours. This homogenization treatment facilitates the subsequent rolling process, and, in the final annealing treatment, in combination with heating to a temperature of 320 ° C. or more at a temperature rising temperature of 10 ° C./min or more, brazing is performed. It is a large and flat recrystallized grain in the heating process of the process to substantially prevent diffusion of Si from the brazing filler metal, and its effect is poor at 530 ° C or lower or less than 1 hour, and 620 ° C. In the above case, burning occurs undesirably. Holding for 15 hours or more is not economical because further effect cannot be expected so much and energy loss occurs.

The ingot homogenized under the above-mentioned conditions is hot-rolled or cold-rolled to a desired plate thickness, and thus the plate rolled to a desired thickness is obtained. Is 320
Strain-introducing processing is performed after heating to a temperature of ℃ or more and the final annealing treatment. This is because the heating rate of heating up to 320 ° C or higher in the final annealing treatment is 10 ° C /
It should be more than a minute. That is, it is clear that if the heating rate is set to 10 ° C./min or more, the recovery and recrystallization process in which Mn is easily precipitated is passed within a short time, and the amount of Mn precipitated is reduced to grow recrystallized grains. Can be easy. The upper limit of the temperature rising rate is, for example, 2000 when the induction heating method is used.
It is possible to raise the temperature at a high speed such as 0 ° C./minute, and it is clear that the higher the speed is, the more preferable from the technical point of the present invention described above. The upper limit of the final annealing temperature is about 620 ° C at which burning occurs.

In the present invention, the strain-introducing work applied after the final annealing performed at the temperature rising rate as described above is 1% or more, whereby the heating process in the subsequent brazing step (up to a temperature of 550 ° C.). Large and flat recrystallized grains are formed in 10 to 60 minutes. That is, part of the plate is Si
In the case where it is alloyed with and melted to form a brazing filler metal, such coarse and flat recrystallized grains reduce the grain boundary area per unit volume, and therefore the grain boundaries serve as diffusion paths. It is clear that the diffusion path of Si in the brazing material in the plane direction is very small and effectively prevents Si diffusion in the plate thickness direction.

Further, since the brazing material formed and melted has excellent fluidity, it flows into the brazing portion to form a sound brazing portion. When the temperature rising rate in the final annealing treatment is less than 10 ° C./minute, the amount of Mn precipitated in the annealing treatment process increases and the growth of recrystallized grains is suppressed. Therefore, after the final annealing, the mild strain introduction working as in the present invention is performed. Then, the recrystallized grains are not sufficiently grown in the subsequent brazing heating process, and it is impossible to reliably prevent Si from the brazing material from diffusing into the recrystallized grains as in the present invention. If the holding temperature in the final annealing treatment is less than 320 ° C, recrystallization is not completed and the increase in elongation is small, resulting in poor formability.

The above-mentioned strain introduction process is as described above. However, if the amount of strain introduction is less than 1%, the temperature increase rate in the final annealing treatment is sufficiently high temperature increase of 10 ° C./minute or more. However, in the heating process of brazing, the above-mentioned large and flat recrystallized grains cannot be obtained, and the penetration of Si component during brazing must be insufficient. On the other hand, if the amount of introduced strain exceeds 5%, the elongation as a plate decreases and the Erichsen value decreases, resulting in poor moldability. Further, the holding time in the final annealing is such that the recrystallization is completed within a short time by annealing under the conditions as described above, and the holding for a long time thereafter is disadvantageous in terms of thermal energy and is economically disadvantageous. Less than a minute is enough.

The crystal grain structure is 70 μ before molding.
A recrystallized grain structure of m or less and 100 μm or more before brazing is formed. That is, if the thickness is 70 μm or more before the molding process, the surface becomes rough during the molding process. If recrystallization is not completed before brazing, the erosion of the member by the generated brazing (through sub-grain boundaries that exist in the grains at a high density)
Is significantly increased and the fillet becomes extremely small. Further, even if recrystallized, if the particle size is smaller than 100 μm,
The erosion of the brazing through the fine grain boundaries increases, and the brazing property decreases.

Explaining a concrete manufacturing example, first, as a first manufacturing example, the test material is prepared by casting the aluminum alloy shown in the following Table 1 into a slab having a thickness of 500 mm, and
After homogenizing at 5 ° C. for 5 hours, a cold-rolled sheet having a thickness of 0.62 mm was produced by hot rolling and cold rolling. Then 350 ° C x 2
After the O material was annealed for a period of time, strain introduction processing was performed by skin pass rolling with a rolling reduction of 3% to obtain a test plate having a thickness of 0.60 mm.

[0036]

[Table 1]

With respect to the test materials obtained as described above, brazing properties, cross-sectional grain structure after brazing, forming processability,
The strength and corrosion resistance after brazing are tested and measured as follows, and the results are shown in Table 2 below. "Brazability" A test piece with a width of 25 mm and a length of 55 mm was cut out from the test plate, immersed in a slurry of a mixture of silicon powder and flux (weight ratio 1: 2) in isopropyl alcohol, and pulled vertically. After drying with warm air, the mixture adhering to one side was removed with a brush. The amount of the adhered mixture at this time was 19 to 21 g / m ² . Then, on the surface coated with the mixture, a thickness of 0.5 mm, a width of 25 mm, and a length of 25 mm
Assemble an inverted T-shaped test piece in which the 03-H14 material is vertically stood, and raise the temperature in a nitrogen gas atmosphere at 50 ° C / min at 600 ° C.
A brazing test with a holding time of 3 minutes was performed. The brazing property was evaluated by measuring the cross-sectional area of the fillet (average of left and right fillets). "Cross-sectional crystal grain structure after brazing" The cross-sectional structure of the test plate after the brazing test was observed by the Barker method. "Moldability" A standard JIS Erichsen A test was performed on the test plate to determine the Erichsen value. "Strength after brazing" The test plate was heated at a temperature rising rate of 50 ° C / min, held at 600 ° C for 3 minutes and then cooled at a rate of 50 ° C / min, and the tensile strength was measured by a normal tensile test. . "Corrosion resistance" A test piece with a width of 50 mm and a length of 110 mm was cut out from the test plate, and a mixture of silicon powder and flux (weight ratio 1: 2) and an acrylic resin-based binder were suspended in pure water on both sides of the test piece. Spray-apply the slurry and apply at 150 ℃ for 5
It was heated for a minute and dried. The adhering amount of the mixture at this time is 19
Was ~ 24 g / m ² . Then, the test piece was fixed vertically on a 3003 plate and brazed at 600 ° C. for 3 minutes in a nitrogen gas atmosphere. After cutting off the joint at the lower end, one side was sealed and subjected to a corrosion resistance test. As a corrosion resistance test, a 14-day CASS test was performed, and the maximum pitting depth generated in the test piece was measured.

[0038]

[Table 2]

Separately from the above-mentioned production example, as a second production example, the aluminum alloys shown in the following Table 3 were cast in a die having a thickness of 30 mm, homogenized at 580 ° C. for 10 hours, and then hot rolled. A cold rolled sheet having a thickness of 0.60 to 64 mm was produced by cold rolling. Next, as an O material annealing, it was put into a furnace kept at 450 ° C., taken out immediately after the temperature of the cold-rolled sheet reached 400 ° C., and air-cooled. After that, strain introduction processing by skin pass rolling with a reduction rate of 2 to 6% is performed or not performed, and the thickness is 0.
A test plate of 60 mm was obtained.

[0040]

[Table 3]

For the test material obtained as described above, the amount of strain required for recrystallization in the brazing process was determined, and the brazing material for the test material was given the minimum strain amount for coarsening the crystal grains. The adhesiveness, the formability, the strength after brazing, and the corrosion resistance were evaluated.
In addition, as the amount required for coarsening, the sample plate having a strain of 2 to 6% was heated at a temperature rising rate of 50 ° C./min, and taken out from the furnace immediately after reaching 570 ° C. to obtain a cross-sectional grain structure. It was observed by the Barker method. However, such measurement results are shown in Table 4 below.
However, since No. 13 has a high Mn amount, the amount of strain required for recrystallization in the brazing process exceeds 5%, and the moldability is deteriorated. Also, it can be seen that the formed fillet is small.

[0042]

[Table 4]

Further, the brazing test results and Erichsen test results for No. 11 material having different introduced strain amounts are as shown in Table 5 below. In the conventional manufacturing method without strain amount, the crystal during brazing was used. Since the grains are fine, the fillet is small. On the other hand, in the comparative manufacturing method in which the strain amount is 6%, the Erichsen value is small and the moldability is deteriorated, as shown in Table 5.

[0044]

[Table 5]

[0045]

As described above, according to the present invention, the formability as an aluminum alloy plate used as a laminated evaporator of a heat exchanger, a fluid passage forming laminated plate of a laminated oil cooler, a header plate of a radiator, etc. It has excellent brazing properties, a large amount of brazing filler metal is formed during brazing, good brazing fluidity, sufficient fillet formation, and excellent brazing strength and corrosion resistance. It is an invention that has effects such as obtaining and has a great effect industrially.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yuichi Nishimura Inventor Yuichi Nishimura 1-34-1 Kambara, Kambara-cho, Anbara-gun, Shizuoka Japan Light Metal Co., Ltd. Group Technology Center (72) Yuan Ichikawa Kambara-cho, Anbara-gun, Shizuoka 1-34-1 1 Nippon Light Metal Co., Ltd. Group Technology Center

Claims (5)

[Claims] 1. A material which partially forms an alloy with a metal and melts to form a brazing material, wherein wt% is Si: 0.4 to 1.6%, Cu: 0.4 to 1.0. %, Ti: 0.05 to 0.
An aluminum alloy plate for non-corrosive flux brazing, characterized in that it contains 3%, the balance is Al and unavoidable impurities, and the content of Mg as impurities is 0.2% or less. 2. A material which is partially alloyed with a metal and melted to form a brazing material, wherein wt% is Si: 0.4 to 1.6%, Cu: 0.4 to 1.0. %, Ti: 0.05 to 0.
3%, Mn: 0.3-0.8%, balance Al and unavoidable impurities, and Mg as an impurity is 0.2% or less, for non-corrosive flux brazing Aluminum alloy plate. 3. A material which is partially alloyed with a metal and melted to form a brazing filler metal, which is composed of the composition according to claim 1 or 2 and has an average recrystallized grain size. An aluminum alloy plate for non-corrosive flux brazing, which has a grain size of 70 μm or less and a strain of 1 to 5% is introduced. 4. An aluminum alloy ingot having a composition according to claim 1, which is a material partially alloyed with a metal and melted to form a brazing filler metal, at a temperature of 400 to 620 ° C.
After holding for ~ 15 hours to homogenize, it is hot-rolled and cold-rolled into a plate having a predetermined thickness, and this plate is heated to 280 ° C.
A final annealing treatment is performed at the above temperature for a holding time of 5 hours or less to make the average grain size of recrystallized grains 70 μm or less, and thereafter, the plate is subjected to strain introduction processing of 1 to 5%. Manufacturing method of aluminum alloy plate for non-corrosive flux brazing. 5. A material which is partially alloyed with a metal and melted to form a brazing filler metal, and the aluminum alloy ingot having the composition according to claim 2 is heated at a temperature of 530 to 620 ° C. for 1 to 15
After holding for a period of time to perform homogenization treatment, hot rolling and cold rolling are performed to obtain a plate having a predetermined thickness, and the plate is held at a temperature rising rate of 10 ° C./min or more at a temperature of 320 ° C. or more for a holding time of 10 Aluminum for non-corrosive flux brazing, characterized in that the final annealing treatment is performed within a period of time to reduce the average grain size of recrystallized grains to 70 μm or less, and then the plate is subjected to 1-5% strain introduction processing. Method for manufacturing alloy plate.