JP2014114475A - Aluminum alloy brazing sheet, method of producing the same, and heat exchanger employing the aluminum alloy brazing sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aluminum alloy brazing sheet with excellent brazing ability and corrosion resistance, to provide a method of producing the same, and to provide a heat exchanger employing the aluminum alloy brazing sheet.SOLUTION: There is provided: an aluminum alloy brazing sheet including a core material made of an aluminum alloy and a sacrificial material with brazing ability clad on at least one surface of the core material, the core material comprising Mn, Fe, and the balance of aluminum and inevitable impurities, the sacrificial material with the brazing ability comprising Si, Zn, Fe, and the balance of aluminum and inevitable impurities, a cladding ratio in the sacrificial material with the brazing ability being 3-25%, the core material having a fibrous structure and the sacrificial material with brazing ability having a recrystallized structure, as metallographic structures before heating for brazing; a method of producing the aluminum alloy brazing sheet; and a heat exchanger employing the aluminum alloy brazing sheet.

Description

  The present invention relates to an aluminum alloy brazing sheet, a method for producing the same, and a heat exchanger using the same, and more particularly, a highly corrosion-resistant aluminum alloy that is suitably used as a refrigerant or air passage component in the heat exchanger. The present invention relates to a brazing sheet and a method for producing the same, and a high corrosion resistance heat exchanger using the brazing sheet.

  Aluminum alloys are lightweight and have high thermal conductivity, and can be realized with high corrosion resistance by appropriate processing. Therefore, they are used in automotive heat exchangers such as radiators, condensers, evaporators, heaters, and intercoolers. As a tube material for an automotive heat exchanger, an Al—Mn-based aluminum alloy such as 3003 alloy is used as a core material, and a brazing material of an Al—Si based aluminum alloy or a sacrificial anode material of an Al—Zn based aluminum alloy is provided on one side. Or a three-layer clad material obtained by further clad a brazing material of an Al—Si based aluminum alloy with the two-layer clad material. Usually, a heat exchanger for an automobile is manufactured by combining this tube material and a corrugated fin material and brazing at a high temperature of about 600 ° C. In order to join the fin material and the tube material by brazing, it is necessary to supply brazing to the joint surface between these fins and the tube. From the viewpoint of the cost of the fin material and self-corrosion resistance, the fin material is bare. It is preferable to use a tube material having a brazing function.

  If there is a corrosive liquid on the surface inside or outside the tube of this heat exchanger, the tube may penetrate due to the generation of corrosion holes. As a result, air circulating inside and refrigerant such as cooling water leaks. Conventionally, as a method of preventing corrosion of a tube, a method has been adopted in which Zn is added to the fin to lower the corrosion potential and the tube is sacrificed and prevented by the fin. However, in a severe corrosive environment, the sacrificial anticorrosive action by the fins alone is insufficient for corrosion resistance, and it is necessary to clad a sacrificial anode material of an Al—Zn-based aluminum alloy on the tube material. In that case, a material in which a brazing material is clad must be used for the fin material, and it becomes impossible to achieve both the cost and self-corrosion resistance of the fin material described above and the corrosion resistance of the tube. In order to solve such a problem, a technique for cladding a layer having both a brazing function and a sacrificial anticorrosion function on one side of the tube material has been desired.

  As such techniques, in Patent Documents 1 to 3, a brazing sheet in which a sacrificial anode material having a Si content of 1.5 to 6.0% and a larger amount of Si added than before is clad into a core material. Is described. In this way, when a large amount of Si is added to the sacrificial anode material, the grain boundary of the sacrificial anode material dissolves during brazing and acts as a brazing, and brazing with the bare fin is possible. Since some of these remain solid, a sacrificial anticorrosive function can also be exhibited. However, in such a brazing function imparting sacrificial material, Zn is concentrated in the molten brazing formed at the grain boundaries in the cooling process after brazing. Therefore, the corrosion rate of the grain boundary becomes very fast in a corrosive environment, and the sacrificial anticorrosion function is lost early, and there is a problem that sufficient corrosion resistance cannot be obtained.

  In the technique described in Patent Document 1, the sacrificial anode material and the inner fin can be brazed, but there is no description about the metal structure such as the crystal grain size of the brazing function-giving sacrificial material after brazing. . That is, there is no recognition of the problem such as the deterioration of the corrosion resistance due to the preferential corrosion at the grain boundaries of the brazing function-giving sacrificial material as described above, and there is no description or suggestion about the solution.

Moreover, in the technique described in patent document 2, in order to improve the brazing property of a brazing function provision sacrificial material surface, 0.1-1.0 micrometer Si particle | grains are used as a metal structure of a brazing function provision sacrificial material. 15000-40000 pieces / mm ² . However, such Si particles are intended to improve erosion / corrosion resistance, and are not intended to solve the problem of reduced corrosion resistance due to preferential corrosion at the grain boundaries of the brazing function-imparting sacrificial material. Absent.

  Further, Patent Document 3 stipulates that the average crystal grain size in the thickness direction of the brazing function-giving sacrificial material after brazing is 80% or more of the clad thickness of the brazing function-giving sacrificial material. The problem of preferential corrosion at the grain boundaries of the functionalized sacrificial material is recognized. However, the control of 80% or more of the cladding thickness is a measure for preventing crystal grains from falling off due to preferential corrosion. Therefore, even if this prevents the crystal grains from falling off, the corrosion rate at the grain boundary remains the same, and this is insufficient as a measure for improving the corrosion resistance.

JP 2008-188616 A JP 2000-309837 A WO2011 / 034102 Publication

  As described above, when both the brazing function and sacrificial anti-corrosion function are added to one side of the tube material for heat exchangers, the deterioration of corrosion resistance due to preferential corrosion at the grain boundaries of the brazing function-providing sacrificial material is suppressed. It has been difficult to obtain excellent corrosion resistance by the conventional technique.

  The present invention is for solving such a problem, and has a good brazing property in which the core material is not eroded by the molten brazing at the time of brazing, and has excellent corrosion resistance after brazing. An aluminum alloy brazing sheet having an aluminum alloy brazing sheet and a method for producing the aluminum alloy brazing sheet suitably used as a fluid passage component of an automotive heat exchanger, and a heat exchanger using the aluminum alloy brazing sheet For the purpose.

  As a result of intensive studies to solve the above problems, the inventors of the present invention used a brazing function imparted sacrificial material having a specific alloy composition clad on a core material as an aluminum alloy brazing sheet, and a specific metal. By controlling the manufacturing process so as to form a structure, it was found that good brazing properties and excellent corrosion resistance can be obtained, and the present invention has been completed.

  Specifically, the present invention provides the aluminum alloy brazing sheet according to claim 1, comprising an aluminum alloy core material and a brazing function imparting sacrificial material clad on at least one surface of the core material, wherein the core material is Si: 0.05-1.2 mass%, Fe: 0.05-1.2 mass%, Mn: 0.5-2.0 mass%, comprising an aluminum alloy composed of the balance Al and inevitable impurities, the brazing The function-imparting sacrificial material contains Si: 2.5 to 7.0 mass%, Zn: 0.5 to 8.0 mass%, Fe: 0.05 to 1.2 mass%, and is composed of the balance Al and inevitable impurities. The clad rate of the brazing function imparting sacrificial material is 3 to 25% made of an aluminum alloy, and the metal structure of the core material before brazing heat is a fibrous structure. And an aluminum alloy brazing sheet, characterized in that the metal structure before heating brazing of the brazing functionalization sacrificial material is recrystallized structure.

  The present invention provides an aluminum alloy brazing sheet according to claim 2, comprising: an aluminum alloy core material; a brazing function-giving sacrificial material clad on one surface of the core material; and a brazing material clad on the other surface of the core material. The core material contains Si: 0.05 to 1.2 mass%, Fe: 0.05 to 1.2 mass%, Mn: 0.5 to 2.0 mass%, and an aluminum alloy composed of the balance Al and inevitable impurities The brazing function-imparting sacrificial material contains Si: 2.5-7.0 mass%, Zn: 0.5-8.0 mass%, Fe: 0.05-1.2 mass%, and the balance Al. And the brazing filler metal contains Si: 2.5-13.0 mass%, Fe: 0.05-1.2 mass%, The brazing function-giving sacrificial material has a cladding ratio of 3 to 25%, and the metal structure before the brazing heat of the core material is a fibrous structure. The aluminum alloy brazing sheet was characterized in that the metallographic structure of the sacrificial material having a function to be imparted before brazing heat was a recrystallized structure.

  The present invention is the aluminum alloy brazing sheet according to claim 3, comprising an aluminum alloy core material, a brazing function imparting sacrificial material clad on one surface of the core material, and a brazing material clad on the other surface of the core material. The core material contains Si: 0.05 to 1.2 mass%, Fe: 0.05 to 1.2 mass%, Mn: 0.5 to 2.0 mass%, and an aluminum alloy composed of the balance Al and inevitable impurities The brazing function-imparting sacrificial material contains Si: 2.5-7.0 mass%, Zn: 0.5-8.0 mass%, Fe: 0.05-1.2 mass%, and the balance Al. And the brazing filler metal is Si: 7.1 to 13.0 mass%, Fe: 0.05 to 1.2 mass%, Zn: 0 The metal before the brazing heat of the core material is 5 to 8.0%, is made of an aluminum alloy composed of the balance Al and inevitable impurities, the brazing function imparting sacrificial material has a cladding rate of 3 to 25%, The aluminum alloy brazing sheet is characterized in that the structure is a fibrous structure, and the metal structure of the sacrificial material with brazing function is a recrystallized structure before brazing heat.

  The present invention is the aluminum alloy brazing sheet according to claim 4, comprising: an aluminum alloy core material; a brazing function imparting sacrificial material clad on one surface of the core material; and a sacrificial anode material clad on the other surface of the core material. The core material contains Si: 0.05 to 1.2 mass%, Fe: 0.05 to 1.2 mass%, Mn: 0.5 to 2.0 mass%, and consists of the balance Al and inevitable impurities. It consists of aluminum alloy, The said brazing function provision sacrificial material contains Si: 2.5-7.0mass%, Zn: 0.5-8.0mass%, Fe: 0.05-1.2mass%, The sacrificial anode material is made of an aluminum alloy composed of the balance Al and inevitable impurities, and the sacrificial anode material is Zn: 0.5 to 8.0 mass%, Si: 0.05 to 1.5 mass%, F It consists of an aluminum alloy containing 0.05 to 2.0 mass%, the balance being Al and unavoidable impurities, and the clad rate of the brazing function imparting sacrificial material is 3 to 25%, before the brazing heat of the core material The aluminum structure brazing sheet is characterized in that the metal structure in is a fibrous structure, and the metal structure before the brazing function imparting sacrificial material is heat-recrystallized.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the core material includes Cu: 0.05 to 1.2 mass%, Mg: 0.05 to 0.5 mass%, and Ti: 0.05. ~ 0.3 mass%, Zr: 0.05-0.3 mass%, Cr: 0.05-0.3 mass% and V: 0.05-0.3 mass% or more The aluminum alloy contained was used.

  The present invention provides the brazing function-imparting sacrificial material according to any one of claims 1 to 5, wherein the brazing function-imparting sacrificial material is Cu: 0.05 to 0.5 mass%, Mn: 0.05 to 2.0 mass%, Ti: 0.05-0.3 mass%, Zr: 0.05-0.3 mass%, Cr: 0.05-0.3 mass%, V: 0.05-0.3 mass%, Na: 0.001- It was made of an aluminum alloy further containing one or more selected from 0.05 mass% and Sr: 0.001 to 0.05 mass%.

  According to a seventh aspect of the present invention, in the seventh aspect, the brazing material is Cu: 0.05 to 1.2 mass%, Mn: 0.05 to 2.0 mass%, Ti: 0.05-0.3 mass%, Zr: 0.05-0.3 mass%, Cr: 0.05-0.3 mass%, V: 0.05-0.3 mass%, Na: 0.001-0. It was made of an aluminum alloy further containing one or more selected from 05 mass% and Sr: 0.001 to 0.05%.

  According to an eighth aspect of the present invention, in the eighth aspect, the brazing material is Cu: 0.05 to 0.5 mass%, Mn: 0.05 to 2.0 mass%, Ti: 0.05-0.3 mass%, Zr: 0.05-0.3 mass%, Cr: 0.05-0.3 mass%, V: 0.05-0.3 mass%, Na: 0.001-0. It was made of an aluminum alloy further containing one or more selected from 05 mass% and Sr: 0.001 to 0.05%.

  In the ninth aspect of the present invention, the sacrificial anode material according to any one of the fourth, fifth, and sixth aspects includes: Mn: 0.05 to 2.0 mass%, Mg: 0.5 to 3.0 mass%, Ti : 0.05-0.3 mass%, Zr: 0.05-0.3 mass%, Cr: 0.05-0.3 mass%, V: 0.05-0.3 mass%, one or two selected It was made of an aluminum alloy further containing seeds or more.

  The present invention is the method for producing an aluminum alloy brazing sheet according to any one of claims 1, 5, and 6, wherein the aluminum alloy for the core material and the sacrificial material for brazing function is respectively provided. A casting step, a cladding step of cladding a brazing function-giving sacrificial material having a predetermined thickness on at least one surface of the core material ingot, and a cladding hot rolling step of hot rolling the cladding material; A cold rolling step for cold rolling the hot rolled clad material, and one or more annealing steps for annealing the clad material in the middle of the cold rolling step, in the clad hot rolling step, While the temperature is 250 to 400 ° C., it includes two or more rolling passes in which the reduction rate in one pass is 30% or more, and in the final annealing step, the clad material is 200 The aluminum alloy brazing sheet production method is characterized in that the clad material is held at 300 ° C. for 1 to 10 hours and the total rolling reduction in the final cold rolling process following the last annealing process is 5 to 25%. .

  The present invention is the method for producing an aluminum alloy brazing sheet according to any one of claims 2, 3, and 5 to 8, wherein the core material, the brazing function imparting sacrificial material, and the brazing material are used. Each of the aluminum alloy for casting, a brazing function imparting sacrificial material having a predetermined thickness is clad on one surface of the core material ingot, and a brazing material having a predetermined thickness is clad on the other surface. A clad process, a clad hot rolling process for hot rolling the clad material, a cold rolling process for cold rolling the hot rolled clad material, and annealing the clad material once in the cold rolling process In the clad hot rolling step, the rolling pass in which the rolling reduction is 30% or more in one pass while the temperature of the clad material is 250 to 400 ° C. In the final annealing step, the clad material is held at 200 to 300 ° C. for 1 to 10 hours, and the total reduction rate of the clad material in the final cold rolling step following the last annealing step is 5% to 25%. It was set as the manufacturing method of the aluminum alloy brazing sheet characterized by this.

  The present invention provides the method for producing an aluminum alloy brazing sheet according to any one of claims 4, 5, 6, and 9, wherein the core material, the brazing function-imparting sacrificial material, and the sacrificial anode are defined in claim 12. A step of casting each of the aluminum alloys for the material, clad a sacrificial material having a predetermined brazing function on one surface of the core ingot, and a sacrificial anode material having a predetermined thickness on the other surface A cladding process for forming a cladding material, a cladding hot rolling process for hot rolling the cladding material, a cold rolling process for cold rolling the hot rolled cladding material, and annealing the cladding material during the cold rolling process A rolling pass in which the rolling reduction in one pass is 30% or more while the temperature of the clad material is 250 to 400 ° C in the clad hot rolling step. In the final annealing step, the clad material is held at 200 to 300 ° C. for 1 to 10 hours, and the total reduction rate of the clad material in the final cold rolling step following the last annealing step is 5% to 25. %, The aluminum alloy brazing sheet was produced.

  The present invention is the heat exchanger using the aluminum alloy brazing sheet according to any one of claims 1 to 9, wherein the crystal grain size of the brazing function imparting sacrificial material after brazing. Is a heat exchanger characterized by being 80 μm or more.

  The aluminum alloy brazing sheet according to the present invention has good brazing properties since the core material is not eroded by molten brazing during brazing, and has excellent corrosion resistance after brazing. Such an aluminum alloy brazing sheet is particularly suitably used as a fluid passage component of a heat exchanger for automobiles.

It is a schematic diagram which shows the change of the metal structure of the core material and the brazing function imparting sacrificial material before and after brazing of the aluminum alloy brazing sheet according to the present invention. It is a front view of the mini core which has arrange | positioned the corrugated fin material between two brazing sheets.

1. Aluminum alloy brazing sheet The aluminum alloy brazing sheet according to the present invention comprises a core material and a brazing function imparting sacrificial material as essential members, and a brazing material and a sacrificial anode material as additional members, and has high corrosion resistance.
The 1st form on the structure of the aluminum alloy brazing sheet which concerns on this invention is a form provided with the core material and the brazing function provision sacrificial material clad by the at least one surface, Specifically, it is on both surfaces of a core material. This includes the case where the brazing function-giving sacrificial material is clad and the case where the brazing function-giving sacrificial material is clad on one surface and nothing is clad on the other surface. Next, a 2nd form is a form provided with a core material, the brazing function provision sacrificial material clad on the one surface, and the brazing material clad on the other surface. Finally, the third form is a form provided with a core material, a brazing function imparting sacrificial material clad on one surface thereof, and a sacrificial anode material clad on the other surface.
Below, the composition of the aluminum alloy which comprises each member, and its effect | action are demonstrated.

1-1. Core material The core material contains Si, Fe and Mn as essential elements. Si forms an Al—Mn—Si intermetallic compound together with Mn, and improves the strength of the core material by solid solution strengthening by dispersion strengthening or in the aluminum matrix. The Si content is 0.05 to 1.2 mass% (hereinafter simply referred to as “%”). If it exceeds 1.2%, the melting point of the core material decreases, and the possibility that the core material melts during brazing increases. Since Si is also contained as an inevitable impurity, a high-purity aluminum ingot must be used to make it less than 0.05%, resulting in an increase in cost. The Si content is preferably 0.1 to 1.0%.

  Fe easily forms an intermetallic compound having a size that can be a recrystallization nucleus, and coarsens the crystal grain size after brazing to suppress erosion of the core material due to melting brazing. Fe content is 0.05 to 1.2%. If it exceeds 1.2%, the crystal grain size of the core material after brazing becomes fine, and the core material may be eroded by molten brazing. Since Fe is also contained as an inevitable impurity, a high-purity aluminum ingot must be used to make it less than 0.05%, resulting in an increase in cost. The Fe content is preferably 0.1 to 0.7%.

  Mn forms an Al—Mn—Si based intermetallic compound together with Si and improves the strength of the core material by solid solution strengthening by dispersion strengthening or in the aluminum matrix. Mn content is 0.5 to 2.0%. If the content is less than 0.5%, the above effect is insufficient. If the content exceeds 2.0%, a giant intermetallic compound is easily formed during casting, and the plastic workability of the core material is lowered. The Mn content is preferably 0.8 to 1.8%.

  In addition to the above essential elements, it is preferable to add one or more selected from Cu, Mg, Ti, Zr, Cr and V as a selective additive element to the core material. Cu improves the strength of the core material by solid solution strengthening. The Cu content is preferably 0.05 to 1.2%. If it is less than 0.05%, the above effect is insufficient, and if it exceeds 1.2%, the possibility of occurrence of cracks in the core aluminum alloy during casting becomes high. The Cu content is more preferably 0.3 to 1.0%.

Mg improves the strength of the core material by precipitation of Mg ₂ Si. The Mg content is preferably 0.05 to 0.5%. If it is less than 0.05%, the above effect is insufficient, and if it exceeds 0.5%, it is difficult to braze because the flux in Nocolok brazing is deteriorated. The Mg content is more preferably 0.1 to 0.4%.

  Ti improves the strength of the core material by solid solution strengthening. The Ti content is preferably 0.05 to 0.3%. If the content is less than 0.05%, the above effect is insufficient. If the content exceeds 0.3%, a giant intermetallic compound is easily formed in the core material, and the plastic workability of the core material is lowered. The Ti content is more preferably 0.1 to 0.2%.

  Zr improves the strength of the core material by solid solution strengthening, and also acts on the coarsening of crystal grains of the core material after brazing by precipitating an Al—Zr-based intermetallic compound. The Zr content is preferably 0.05 to 0.3%. If it is less than 0.05%, the above effect cannot be obtained. When it exceeds 0.3%, it becomes easy to form a giant intermetallic compound in the core material, and the plastic workability of the core material is lowered. The Zr content is more preferably 0.1 to 0.2%.

  Cr improves the strength of the core material by solid solution strengthening and also acts on the coarsening of crystal grains of the core material after brazing by precipitating an Al—Cr-based intermetallic compound. The Cr content is preferably 0.05 to 0.3%. If it is less than 0.05%, the above effect cannot be obtained. When it exceeds 0.3%, it becomes easy to form a giant intermetallic compound in the core material, and the plastic workability of the core material is lowered. The Cr content is more preferably 0.1 to 0.2%.

  V improves the strength of the core material by solid solution strengthening and also improves the corrosion resistance. The V content is preferably 0.05 to 0.3%. If it is less than 0.05%, the above effect cannot be obtained. If it exceeds 0.3%, it becomes easy to form a giant intermetallic compound in the core material, and the plastic workability is lowered. The V content is more preferably 0.1 to 0.2%.

  The core material may contain inevitable impurities in addition to the above essential elements and selective additive elements, each 0.05% or less, and 0.15% or less in total.

1-2. Brazing function imparting sacrificial material The brazing function imparting sacrificial material used in the present invention refers to a material having both a brazing function and a sacrificial anticorrosion function. Such a brazing function imparting sacrificial material contains Si, Zn, and Fe as essential elements.

  Si lowers the melting point of the brazing function-imparting sacrificial material to produce a liquid phase, thereby enabling brazing. The Si content is 2.5-7.0%. If it is less than 2.5%, only a small liquid phase is generated in the sacrificial material with brazing function, so that brazing does not work. On the other hand, if it exceeds 7.0%, the amount of the liquid phase generated at the time of brazing becomes too large, the brazing function imparting sacrificial material present as the remaining solid phase is reduced, and the corrosion resistance is lowered. The Si content is preferably 3.0 to 6.0%.

  Zn can make the potential lower and can improve the corrosion resistance by the sacrificial anode effect by forming a potential difference with the core material. The Zn content is 0.5 to 8.0%. If it is less than 0.5%, the effect of improving the corrosion resistance due to the sacrificial anode effect cannot be sufficiently obtained. On the other hand, if it exceeds 8.0%, the corrosion rate is increased, the brazing function-giving sacrificial material disappears at an early stage, and the corrosion resistance is lowered. The Zn content is preferably 1.0 to 6.0%.

  Fe easily forms an Al-Fe-based or Al-Fe-Si-based intermetallic compound in a brazing function-giving sacrificial material. The formation of an Al-Fe-Si intermetallic compound reduces the amount of Si effective for lowering the melting point of the brazing function-imparting sacrificial material, and between Al-Fe and Al-Fe-Si intermetallics. The formation of the compound reduces the fluidity of the brazing during brazing. By these, brazing property is inhibited. The content of Fe is 0.05 to 1.2%. When the Fe content exceeds 1.2%, brazing is inhibited as described above. On the other hand, if the Fe content is less than 0.05%, a high-purity aluminum ingot must be used for the brazing function-giving sacrificial material, resulting in an increase in cost. A preferable content of Fe is 0.1 to 0.7%.

  In addition to the above essential elements, one or more selected from Cu, Mn, Ti, Zr, Cr, V, Na, and Sr are added as additive additive elements to the brazing function imparting sacrificial material. Is preferred.

  Cu improves the strength of the brazing function imparting sacrificial material by solid solution strengthening. The Cu content is preferably 0.05 to 0.5%. If it is less than 0.05%, the above effect is insufficient, and if it exceeds 0.5%, the potential of the brazing function-imparting sacrificial material becomes noble and the sacrificial anticorrosive effect is not exhibited. The Cu content is more preferably 0.05 to 0.4%.

  Mn forms an Al—Mn—Si based intermetallic compound together with Si in the brazing function imparting sacrificial material, and improves the strength by solid solution strengthening by dispersion strengthening or by solid solution strengthening. The Mn content is preferably 0.05 to 2.0%. If the content is less than 0.05%, the above effect is insufficient. If the content exceeds 2.0%, a giant intermetallic compound is easily formed in the brazing function-giving sacrificial material at the time of casting, and the plastic workability is lowered. The Mn content is more preferably 0.1 to 1.8%.

  Ti improves the strength of the brazing function imparting sacrificial material by solid solution strengthening and also improves the corrosion resistance. The Ti content is preferably 0.05 to 0.3%. If it is less than 0.05%, the above effect cannot be obtained. If it exceeds 0.3%, it becomes easy to form a giant intermetallic compound in the brazing function imparting sacrificial material, and the plastic workability is lowered. The Ti content is more preferably 0.1 to 0.2%.

  Zr improves the strength by solid solution strengthening in the brazing function-giving sacrificial material, and also precipitates an Al-Zr-based intermetallic compound and acts on coarsening of the crystal grains after brazing. The Zr content is preferably 0.05 to 0.3%. If it is less than 0.05%, the above effect cannot be obtained. If it exceeds 0.3%, it becomes easy to form a giant intermetallic compound in the brazing function imparting sacrificial material, and the plastic workability is lowered. The Zr content is more preferably 0.1 to 0.2%.

  Cr improves strength by solid solution strengthening in the brazing function-giving sacrificial material, and also precipitates an Al—Cr intermetallic compound and acts on coarsening of crystal grains after brazing. The Cr content is preferably 0.05 to 0.3%. If it is less than 0.05%, the above effect cannot be obtained. When it exceeds 0.3%, it becomes easy to form a giant intermetallic compound in the brazing function imparting sacrificial material, and the plastic workability is lowered. The Cr content is more preferably 0.1 to 0.2%.

  V improves the strength of the brazing function imparting sacrificial material by solid solution strengthening and also improves the corrosion resistance. The V content is preferably 0.05 to 0.3%. If it is less than 0.05%, the above effect may not be obtained. If it exceeds 0.3%, it becomes easy to form a giant intermetallic compound in the brazing function imparting sacrificial material, and the plastic workability is lowered. The V content is more preferably 0.1 to 0.2%.

  By adding Na and Sr to the brazing function imparting sacrificial material, the size of the Si particles is finely and uniformly dispersed to control the generation of coarse Si particles. As a result, local melting and occurrence of erosion are suppressed at the joint between the brazing function imparting sacrificial material and the core material or the fin material. Moreover, it contributes to strength improvement through the action of finely and uniformly dispersing the size of the Si particles. The Na and Sr contents are each preferably 0.001 to 0.05%. If it is less than 0.001%, the above effect cannot be obtained sufficiently. On the other hand, since Na and Sr promote the oxidation of aluminum, if it exceeds 0.05%, the oxidation of the braze proceeds at the time of brazing, and the fluidity and brazeability of the braze are lowered. The contents of Na and Sr are more preferably 0.005 to 0.015%.

  The brazing function imparting sacrificial material may contain inevitable impurities in addition to the essential elements and the selective additive elements, each 0.05% or less, and 0.15% or less in total.

1-3. Brazing material The brazing material contains Si and Fe as essential elements. Si lowers the melting point of the brazing material to form a liquid phase and enables brazing. The Si content is set to 2.5 to 13.0%. If it is less than 2.5%, the liquid phase generated in the brazing material is small, and brazing becomes difficult to function. On the other hand, if it exceeds 13.0%, for example, when this brazing material is used as a tube material, the amount of Si that diffuses into the joining partner material such as fins during brazing becomes excessive, and the joining partner material melts. . The Si content is preferably 3.0 to 12.0%.

  Fe easily forms an Al-Fe-based or Al-Fe-Si-based intermetallic compound in the brazing material. The amount of Si effective for lowering the melting point of the brazing material is reduced by forming an Al—Fe—Si intermetallic compound, and the Al—Fe and Al—Fe—Si intermetallic compounds in the brazing material are reduced. The formation reduces the fluidity of the brazing during brazing. By these, brazing property is inhibited. The Fe content is 0.05 to 1.2%. If the Fe content exceeds 1.2%, brazing properties are inhibited as described above. On the other hand, if the Fe content is less than 0.05%, high-purity aluminum ingots must be used, leading to an increase in cost. The Fe content is preferably 0.1 to 0.7%.

  In addition to the above essential elements, it is preferable to add one or two or more selected from Cu, Mn, Ti, Zr, Cr, V, Na and Sr as selective additive elements to the brazing material. Cu improves the brazing filler metal strength by solid solution strengthening. The Cu content is preferably 0.05 to 1.2%. If it is less than 0.05%, the above effect is insufficient, and if it exceeds 1.2%, the possibility of occurrence of cracks in the aluminum alloy at the time of casting of the brazing material increases. The Cu content is more preferably 0.3 to 1.0%.

  Mn forms an Al—Mn—Si-based intermetallic compound together with Si in the brazing material, and improves its strength by dispersion strengthening and by solid solution in the aluminum matrix and by solid solution strengthening. The Mn content is preferably 0.05 to 2.0%. If it is less than 0.05%, those effects are insufficient, and if it exceeds 2.0%, a giant intermetallic compound is likely to be formed at the time of casting of the brazing material, and the plastic workability is lowered. The Mn content is more preferably 0.1 to 1.8%.

  Ti improves the brazing filler metal strength by solid solution strengthening and also improves the corrosion resistance. The Ti content is preferably 0.05 to 0.3%. If it is less than 0.05%, those effects cannot be obtained. If it exceeds 0.3%, a huge intermetallic compound is easily formed in the brazing material, and the plastic workability is lowered. The Ti content is more preferably 0.1 to 0.2%.

  Zr improves the strength of the brazing material by solid solution strengthening, and acts on the coarsening of crystal grains after brazing by precipitating an Al—Zr-based intermetallic compound in the brazing material. The Zr content is preferably 0.05 to 0.3%. If it is less than 0.05%, those effects cannot be obtained. If it exceeds 0.3%, a large intermetallic compound is easily formed in the brazing material, and the plastic workability is lowered. The Zr content is more preferably 0.1 to 0.2%.

  Cr improves the strength of the brazing material by solid solution strengthening, and acts on the coarsening of the crystal grains after brazing by precipitating an Al—Cr intermetallic compound in the brazing material. The Cr content is preferably 0.05 to 0.3%. If it is less than 0.05%, those effects cannot be obtained. If it exceeds 0.3%, a large intermetallic compound is easily formed in the brazing material, and the plastic workability is lowered. The Cr content is more preferably 0.1 to 0.2%.

  V improves the strength of the brazing filler metal by solid solution strengthening and also improves the corrosion resistance. The V content is preferably 0.05 to 0.3%. If it is less than 0.05%, these effects may not be obtained. If it exceeds 0.3%, a large intermetallic compound is easily formed in the brazing material, and the plastic workability is lowered. The V content is more preferably 0.1 to 0.2%.

  By adding Na and Sr, the size of the Si particles is finely and uniformly dispersed in the brazing material, and the generation of coarse Si particles is controlled. As a result, for example, when a brazing material is used for the tube material, local melting and erosion are suppressed at the joint portion with the core material or the fin material. Moreover, it contributes to strength improvement through the action of finely and uniformly dispersing the size of the Si particles. The Na and Sr contents are each preferably 0.001 to 0.05%. If it is less than 0.001%, the above effect cannot be obtained sufficiently. On the other hand, since Na and Sr promote the oxidation of aluminum, if it exceeds 0.05%, the oxidation of the braze proceeds at the time of brazing, and the fluidity and brazeability of the braze are lowered. The contents of Na and Sr are more preferably 0.005 to 0.015%.

  The brazing filler metal may contain inevitable impurities in addition to the above essential elements and selective additive elements, each 0.05% or less, and 0.15% or less in total.

  In the modified example of the above alloy composition (hereinafter referred to as “basic example”), the brazing material has different Si content as an essential element in the basic example, and further contains Zn as an essential element. Moreover, Cu content as a selective addition element differs from a basic example. The other alloy components are the same as the basic example including inevitable impurities.

  The Si content in the modified example is preferably 7.1 to 13.0%. In the case of less than 7.1%, since there are many ratios which exist as a residual solid phase at the time of brazing, the function as a brazing function imparting sacrificial material already described will be achieved. On the other hand, if it exceeds 13.0%, for example, when this brazing material is used as a tube material, the amount of Si that diffuses into the joining partner material such as fins during brazing becomes excessive, and the joining partner material melts. . The Si content is more preferably 7.1 to 12.0%.

  In the modified example, Zn is further contained as an essential element. Zn is preferably contained because the potential can be reduced and the corrosion resistance can be improved by the sacrificial anode effect by forming a potential difference with the core material. The Zn content is preferably 0.5 to 8.0%. If it is less than 0.5%, the effect of improving the corrosion resistance due to the sacrificial anode effect may not be sufficiently obtained. If it exceeds 8.0%, for example, when this brazing material is used for a tube material, In FIG. 2, Zn concentrates in the joint portion with the joining partner material such as the fin material, and this preferentially corrodes and peels off the joining partner material. The Zn content is more preferably 1.0 to 6.0%.

  In the modified example, Zn is an essential element. However, when Cu is contained as a selective element, Cu makes the brazing material potential noble and loses the sacrificial anticorrosive effect of Zn, so the Cu content is 0.05 to 0.5% is preferable. If it is less than 0.05%, the strength improvement of the brazing filler metal due to solid solution strengthening will be insufficient, and if it exceeds 0.5%, the possibility of cracking of the aluminum alloy for brazing during casting becomes high. The Cu content is more preferably 0.3 to 0.4%.

1-4. Sacrificial anode material The sacrificial anode material contains Zn, Si and Fe as essential elements. Zn can lower the potential of the sacrificial anode material, and can improve the corrosion resistance by the sacrificial anode effect by forming a potential difference with the core material. The Zn content is 0.5 to 8.0%. If the content is less than 0.5%, the above effect is not sufficient. If the content exceeds 8.0%, the corrosion rate is increased, the sacrificial anode material disappears early, and the corrosion resistance decreases. The Zn content is preferably 1.0 to 6.0%.

In the sacrificial anode material, Si forms an Al-Fe-Mn-Si intermetallic compound together with Fe and Mn to improve the strength by dispersion strengthening, or solid solution strengthens by dissolving in the aluminum matrix. To improve strength. In addition, the strength of the sacrificial anode material is improved by reacting with Mg diffused from the core material to the sacrificial anode material during brazing to form an Mg ₂ Si compound. The Si content is 0.05 to 1.5%. If it is less than 0.05%, a high-purity aluminum ingot must be used, resulting in an increase in cost. On the other hand, if it exceeds 1.5%, the melting point of the sacrificial anode material is lowered and melted at the time of brazing, and the sacrificial anode material is made noble to inhibit the sacrificial anode effect and reduce the corrosion resistance. . The Si content is preferably 0.05 to 1.2%.

  Fe forms an Al—Fe—Mn—Si intermetallic compound together with Si and Mn in the sacrificial anode material, and improves the strength by dispersion strengthening. The Fe content is 0.05 to 2.0%. If it is less than 0.05%, a high-purity aluminum ingot must be used, resulting in an increase in cost. On the other hand, if it exceeds 2.0%, a huge intermetallic compound is easily formed during the casting of the sacrificial anode material, and the plastic workability is lowered. The Fe content is preferably 0.05 to 1.5%.

  In addition to the above essential elements, the sacrificial anode material is preferably added with one or more selected from Mn, Mg, Ti, Zr, Cr and V as a selective additive element. Mn is preferably contained because it improves the strength and corrosion resistance of the sacrificial anode material. The Mn content is preferably 0.05 to 2.0%. If it exceeds 1.8%, a giant intermetallic compound is likely to be formed in the sacrificial anode material at the time of casting, and the plastic workability may be deteriorated. In addition, since the potential of the sacrificial anode material is made noble, the sacrificial anode effect is inhibited. As a result, the corrosion resistance may be reduced. On the other hand, if it is less than 0.05%, the effects of the above-described plastic workability and corrosion resistance may not be sufficient. The Mn content is more preferably 0.05 to 1.5%.

Mg improves the strength of the sacrificial anode material by precipitation of Mg ₂ Si. In addition to improving the strength of the sacrificial anode material itself, brazing causes Mg to diffuse from the sacrificial anode material to the core material, thereby improving the strength of the core material. For these reasons, it is preferable to contain Mg. The content of Mg is preferably 0.5 to 3.0%. If it is less than 0.5%, those effects may not be sufficiently obtained, and if it exceeds 3.0%, it becomes difficult to press the sacrificial anode material and the core material in the clad hot rolling process. The Mg content is more preferably 0.5 to 2.0%. In addition, since Mg deteriorates the flux in noco rock brazing and inhibits brazing, noco rock brazing cannot be used when the sacrificial anode material contains 0.5% or more of Mg. In this case, it is necessary to use means such as welding for joining the tubes, for example.

  Ti is preferably contained because it can improve the strength of the sacrificial anode material by solid solution strengthening and can improve the corrosion resistance. The Ti content is preferably 0.05 to 0.3%. If it is less than 0.05%, those effects cannot be obtained. On the other hand, if it exceeds 0.3%, a giant intermetallic compound is easily formed in the sacrificial anode material, and the plastic workability may be lowered. The Ti content is more preferably 0.05 to 0.2%.

  Zr improves the strength of the sacrificial anode material by solid solution strengthening, and Al-Zr-based intermetallic compounds are precipitated in the sacrificial anode material and act on the coarsening of the crystal grains after brazing. preferable. The Zr content is preferably 0.05 to 0.3%. If it is less than 0.05%, those effects cannot be obtained. On the other hand, if it exceeds 0.3%, a giant intermetallic compound is easily formed in the sacrificial anode material, and the plastic workability may be lowered. The Zr content is more preferably 0.1 to 0.2%.

  Cr improves the strength of the sacrificial anode material by solid solution strengthening, and Al—Cr-based intermetallic compounds are precipitated in the sacrificial anode material and act on the coarsening of the crystal grains after brazing. preferable. The Cr content is preferably 0.05 to 0.3%. If it is less than 0.05%, those effects cannot be obtained. On the other hand, if it exceeds 0.3%, it becomes easy to form a giant intermetallic compound in the sacrificial anode material, and the plastic workability may be lowered. The Cr content is more preferably 0.1 to 0.2%.

  V is preferably contained because it can improve the strength of the sacrificial anode material by solid solution strengthening and can improve the corrosion resistance. The V content is preferably 0.05 to 0.3%. If it is less than 0.05%, those effects cannot be obtained. On the other hand, if it exceeds 0.3%, a giant intermetallic compound is easily formed in the sacrificial anode material, and the plastic workability may be lowered. The V content is more preferably 0.05 to 0.2%.

2. First, the metal structure before brazing in the highly corrosion-resistant aluminum alloy brazing sheet of the present invention will be described. The aluminum alloy brazing sheet of the present invention is characterized in that, in the state before brazing, the core material is a fiber structure and the brazing function-imparting sacrificial material is a recrystallized structure.

  Next, changes in the metal structure before and after brazing will be described. In the manufacturing process of an aluminum alloy brazing sheet, when the core material is recrystallized by annealing and then cold rolling with a low rolling reduction is applied, the metal structure of the core material becomes a recrystallized structure with slight distortion. When the core material before brazing is in a state of a recrystallized structure having a slight strain as described above, the core material is recrystallized again by heat input during brazing. However, since the amount of strain is small, the driving force for recrystallization is small, and since the core material contains many fine intermetallic compounds that suppress recrystallization, the core material after brazing has a recrystallized structure in which subgrains remain. It becomes.

  On the other hand, in the manufacturing process of the aluminum alloy brazing sheet, when the core material is not recrystallized by annealing, the metal structure of the core material becomes a fibrous structure with a large strain. When the core material before brazing is in the state of a fibrous structure in this way, the driving force of recrystallization increases due to the large strain in the metal structure of the core material, and the core material after brazing does not have subgrains remaining. It becomes a crystal structure.

  On the other hand, the brazing function-giving sacrificial material has few fine intermetallic compounds that suppress recrystallization. Therefore, even if the metallographic structure of the brazing function-imparted sacrificial material before brazing is in the state of a recrystallized structure with slight distortion, the brazed function-imparted sacrificial material after brazing does not have subgrains remaining. It becomes a crystal structure. If the metal structure of the brazing function-giving sacrificial material before brazing is in a fibrous structure with a large strain, the driving force for recrystallization by heat input during brazing is the same as in the case of the core material. The brazing function-giving sacrificial material after brazing becomes a fine recrystallized structure in which no subgrains remain.

  FIG. 1 is a schematic diagram of a metal structure in a core material and a brazing function imparting sacrificial material of a brazing sheet of the present invention. As shown to (a), in the state before brazing, the core material is in a fibrous structure state, and the brazing function imparting sacrificial material is in a recrystallized structure state. In the state after brazing, as shown in (b), both the core material and the brazing function imparting sacrificial material are in a recrystallized structure, and the core material is not eroded by brazing. The state of such a metal structure can be confirmed by mirror-polishing the cross-section of the brazing sheet, performing Barker etching, and observing with a deflection microscope.

  Next, the relationship between the metal structure before and after brazing of the brazing function imparting sacrificial material in the aluminum alloy brazing sheet of the present invention and the corrosion resistance will be described. As described above, at the crystal grain boundaries of the brazing function-giving sacrificial material after brazing, the corrosion rate due to Zn concentration increases. Therefore, if there are many crystal grain boundaries in the brazing function imparting sacrificial material, the corrosion resistance is lowered. Therefore, in order to reduce the portion of the crystal grain boundary after brazing, that is, to make the crystal grain coarse, it is sufficient that the amount of strain contained in the brazing function-giving sacrificial material in the state before brazing is small. The brazing function-imparting sacrificial material has almost no fine intermetallic compound that suppresses recrystallization. A recrystallized structure in which no subgrains remain can be obtained. Thus, if the brazing function imparting sacrificial material before brazing is a recrystallized structure having a slight strain, coarse crystal grains can be obtained after brazing. On the other hand, if the brazing function-imparting sacrificial material before brazing is in the state of a fiber structure with a large strain, the amount of strain contained in the brazing function-giving sacrificial material is large. Becomes finer and corrosion resistance decreases.

  On the other hand, if the amount of strain before brazing is small in the core material, subgrains remain in the core material during brazing. If it does so, it will spread | diffuse from a brazing function provision sacrificial material to a core material, but will penetrate | invade into the inside of a core material along the said subgrain of a core material, and erosion of the core material by brazing will generate | occur | produce. As a result, the amount of wax flowing on the surface of the brazing sheet is reduced, and unbonded with the counterpart material such as fins may occur. In this case, if the core material before brazing is in a fiber structure, the amount of strain contained in the core material is large, so that no subgrains remain in the recrystallization of the core material that occurs during brazing. As a result, since the core material is not eroded by the wax, a decrease in the strength of the core material is avoided.

  As described above, in the aluminum alloy brazing sheet of the present invention, the brazing function imparting sacrificial material is in a recrystallized structure state and the core material is in a fibrous structure state before brazing. As a result, only the amount of strain contained in the brazing function-giving sacrificial material can be reduced, and the crystal grains of the brazing function-giving sacrificial material after brazing can be coarsened to improve the corrosion resistance. The brazing erosion from the brazing material to the core material can be suppressed, and unbonding with a mating material such as a fin can be prevented.

  When the brazing material or sacrificial anode material is clad on the surface opposite to the surface on which the brazing function-imparting sacrificial material is clad, the metal structure of these brazing material and sacrificial anode material is not particularly limited. No.

3. Crystal grain size after brazing In the aluminum alloy brazing sheet of the present invention, the crystal grain size of the brazing function imparting sacrificial material is 80 μm or more in the state after brazing. The crystal grain size is measured by observing the surface of the brazing function-giving sacrificial material after brazing, and is represented by the equivalent circle diameter of the crystal grain.

  As already described, in order to improve the corrosion resistance, it is necessary that the crystal grain size of the brazing function-giving sacrificial material after brazing is coarse. If the crystal grain size of the brazing function imparted sacrificial material after brazing is 80 μm or more, the crystal grain boundary portion is sufficiently reduced, and excellent corrosion resistance can be obtained. The crystal grain size of the brazing function-imparting sacrificial material after brazing is preferably 100 μm or more. Moreover, although an upper limit is not specifically limited, It is difficult to set it as 1000 micrometers or more.

4). Manufacturing method of aluminum alloy brazing sheet 4-1. Embodiment of Manufacturing Method In the first embodiment, the manufacturing method of the aluminum alloy brazing sheet of the present invention is the step of casting aluminum alloys for the core material and the brazing function-giving sacrificial material, respectively, and the cast brazing function-giving sacrificial material. A hot rolling process in which the ingot is hot-rolled to a predetermined thickness, a cladding process in which a brazing function-giving sacrificial material hot-rolled on at least one surface of the core material ingot is clad to form a clad material, and a clad material Including a hot-clad clad hot-rolling process, a cold-rolling process for cold-rolling the hot-rolled clad material, and one or more annealing processes for annealing the clad material during the cold-rolling process. . Here, the hot-rolling step of the brazing function-provided sacrificial material ingot before the cladding step is one method for setting the brazing function-provided sacrificial material ingot to a predetermined thickness, and is not related to hot rolling. A method for obtaining a predetermined thickness, such as a predetermined thickness by cutting or the like, may be appropriately selected.

  In the second embodiment of the method for producing an aluminum alloy brazing sheet of the present invention, in the steps of the first embodiment, the step of casting an aluminum alloy for brazing material and hot rolling the cast brazing material ingot to a predetermined thickness A hot rolling step, and further including a step of cladding the hot-rolled brazing material on the other surface of the core material ingot. Further, in the third embodiment of the method for producing an aluminum alloy brazing sheet of the present invention, the step of casting the aluminum alloy for the sacrificial anode material and the cast sacrificial anode material ingot in the step of the first embodiment have a predetermined thickness. A hot rolling step of hot rolling to a thickness, and further including a step of cladding a sacrificial anode material on the other surface of the core material ingot. Here, the hot rolling step of the brazing material ingot before the cladding step in the second embodiment, and the hot rolling step of the sacrificial anode material ingot before the cladding step in the third embodiment are performed as follows: This is one method for setting the sacrificial anode material ingots to a predetermined thickness, and a method for setting the predetermined thickness, such as a predetermined thickness by chamfering or the like without using hot rolling, may be appropriately selected.

4-2. Casting process and hot rolling process There are no particular limitations on the conditions in the casting process, but it is usually carried out by water-cooled semi-continuous casting. In the hot rolling step, the heating temperature is usually preferably about 400 to 560 ° C. If it is less than 400 ° C., cracking or the like may occur during rolling because of poor plastic workability. When the temperature is higher than 560 ° C., the brazing function imparting sacrificial material or the brazing material may be melted during the heating.

4-3. Clad hot rolling process In each of the first to third embodiments, in the clad hot rolling process, the rolling reduction in one pass is 30% or more while the temperature of the clad material is 250 to 400 ° C. It is characterized by including a pass twice or more.

  The clad hot rolling process may be divided into a rough rolling process and a finish rolling process. In the finish rolling process, a reverse type or tandem type rolling mill is used. In a reverse rolling mill, one-way rolling is defined as one pass, and in a tandem rolling mill, rolling with one set of rolling rolls is defined as one pass.

  As described above, in the aluminum alloy brazing sheet of the present invention, it is necessary that the sacrificial material with brazing function is in a recrystallized state and the core material is in a fiber structure before brazing. As a result of the inventors' diligent research, by applying a large shear strain to the brazing function-provided sacrificial material in the clad hot rolling process, only the brazing function-provided sacrificial material is driven in the subsequent annealing process. Can be increased. As a result, it was found that before brazing, the core material can be made into a metal structure in the state of fiber structure, and the sacrificial material with brazing function can be made into a metal structure in the state of recrystallized structure.

  In addition, by making the temperature at the time of clad hot rolling lower and making the rolling reduction in one pass higher, a larger shear strain tends to enter the aluminum material. Specifically, the shear strain that enters the brazing function-giving sacrificial material when the temperature of the clad material is 250 to 400 ° C. and the rolling pass at which the reduction rate is 30% or more is included twice or more in the clad hot rolling process. Is sufficiently large, and it is possible to obtain a core material in a state of a fiber structure, which is a target metal structure, and a brazing function imparting sacrificial material in a state of a recrystallized structure. As long as the temperature of the clad material exceeds 400 ° C. in the clad hot rolling process, dynamic recovery occurs during clad hot rolling, so two or more rolling passes with a reduction ratio of 30% or more are performed. However, the shear strain entering the sacrificial material with brazing function is not increased, and a desired metal structure cannot be obtained. On the other hand, when the temperature of the clad material in the clad hot rolling process is less than 250 ° C., cracking occurs during hot rolling, and a brazing sheet cannot be produced. In addition, when the rolling reduction rate in one pass is less than 30%, the shear strain entering the brazing function-giving sacrificial material is not increased, and a desired metal structure cannot be obtained.

  In the clad hot rolling process, there is no particular upper limit for the number of passes with a reduction rate of 30% or more while the temperature of the clad material is 250 to 400 ° C., but setting it to 5 passes or more is a crack during hot rolling. It is preferable to use 2 to 4 passes. Moreover, it is preferable to heat at 400-550 degreeC for 1 to 10 hours before clad hot rolling. If the heating temperature is less than 400 ° C., the material temperature at the time of rolling is too low, and there is a risk of material cracking during rolling. On the other hand, if the heating temperature exceeds 550 ° C., the brazing function imparting sacrificial material may be melted. In addition, when the heating time is less than 1 hour, the material temperature is difficult to be uniform. On the other hand, when the heating time exceeds 10 hours, productivity may be significantly impaired. In addition, although there is no restriction | limiting in particular in the board thickness after clad hot rolling, Usually, it manufactures to about 2.0-5.0 mm.

4-4. Annealing Step In the first to third embodiments, the clad material is held at 200 to 300 ° C. for 1 to 10 hours in the final annealing step performed before the final cold rolling step.

  The annealing process is performed for the purpose of adjusting the strain in the material. By this process, only the brazing function-giving sacrificial material is recrystallized, and the brazing function-giving sacrificial material is brought into a recrystallized state as described above. And the metal structure which makes a core material the state of a fiber structure can be obtained. When the clad material temperature in the final annealing step is less than 200 ° C. or the holding time is less than 1 hour, the recrystallization of the brazing function imparting sacrificial material is not completed. When the annealing temperature exceeds 300 ° C., the core material is also in a recrystallized state. Further, even if the holding time exceeds 10 hours, the target metal structure can be obtained, but the productivity is remarkably impaired.

  The annealing process is performed once or more during the cold rolling process. The upper limit of the number of times is not particularly limited, but is preferably 3 times or less in order to avoid an increase in cost due to an increase in the number of steps. Further, for the purpose of adjusting the material strength before brazing, a further annealing step may be performed after cold rolling to the final thickness. The annealing step here is also preferably performed at 200 to 300 ° C. for 1 to 10 hours.

4-5. Final cold rolling step The first to third embodiments are further characterized in that the total rolling reduction of the clad material in the final cold rolling step following the last annealing step is 5 to 25%.

  As described above, in order to increase the crystal grain size of the brazing function-giving sacrificial material after brazing, the amount of strain contained in the material in the state before brazing should be small. Even if the brazing function-imparting sacrificial material is in a recrystallized state by the clad hot rolling process and annealing process, if a large reduction is applied in the final cold rolling, the brazing function-giving sacrificial material after brazing The crystal grain size becomes fine. Therefore, by setting the total reduction ratio of the clad material in the final cold rolling step to 5 to 25%, the crystal grain size of the brazing function-giving sacrificial material after brazing becomes coarse, and excellent corrosion resistance can be obtained. . If the total rolling reduction exceeds 25%, the crystal grain size of the brazing function-imparting sacrificial material after brazing becomes fine, and the corrosion resistance decreases. Moreover, if the total rolling reduction is less than 5%, stable rolling cannot be performed. In addition, although there is no restriction | limiting in particular in the final board thickness after final cold rolling, Usually, it manufactures as a board | plate material of 0.2 mm or more and 0.6 mm or less, and may manufacture as a thin board material of 0.1 mm or more and less than 0.2 mm. it can.

4-6. Homogenization processing step In the first to third embodiments, the core material ingot may be subjected to a homogenization processing step after the core material casting step. The homogenization treatment step is performed mainly for the purpose of adjusting the material strength before brazing for the purpose of improving the moldability. As conditions for the homogenization treatment step, the core material ingot is preferably maintained at a temperature of 500 to 620 ° C. for 1 to 20 hours. When the holding temperature is less than 500 ° C. or when the holding time is less than 1 hour, the material strength may not be appropriately adjusted. When holding temperature exceeds 620 degreeC, there exists a possibility that a core material ingot may melt | dissolve. If the holding time exceeds 20 hours, there is no problem in adjusting the material strength, but the productivity is significantly impaired.

4-7. Clad rate In the aluminum alloy brazing sheet of the present invention, the clad rate (one side) of the brazing function-giving sacrificial material is 3 to 25%. As described above, it is necessary to apply a large shear strain only to the brazing function-giving sacrificial material in the clad hot rolling process during the manufacturing process. However, if the clad rate of the brazing function-giving sacrificial material exceeds 25%, sufficient shear strain is not applied to the entire brazing function-giving sacrificial material, and the entire brazing function-giving sacrificial material cannot have a recrystallized structure. . On the other hand, if the clad rate is less than 3%, the brazing function-imparting sacrificial material is too thin, so that the brazing function-giving sacrificial material cannot be covered over the entire core material during the hot rolling of the clad. The cladding rate is preferably 5 to 20%.

  In addition, when the brazing function imparting sacrificial material is clad on one surface of the core material and the brazing material or sacrificial anode material is clad on the other surface, the clad rate of the brazing material and the sacrificial anode material is not particularly limited. However, it is usually clad at about 3 to 30%.

5. Heat exchanger The aluminum alloy brazing sheet is suitably used as a heat exchanger member such as a tube material and a header plate, particularly as a tube material. For example, the aluminum alloy brazing sheet is bent, and the overlapping portions at both ends thereof are brazed and joined to produce a tube material for flowing a medium such as cooling water. Moreover, the said aluminum alloy brazing sheet is processed, and the header plate provided with the hole joined with the both ends of a tube material is produced. The aluminum heat exchanger according to the present invention has a structure in which, for example, the above-described tube material, fin material, and header plate are combined and brazed at the same time.

  In the heat exchanger that has been brazed and bonded under normal conditions using such a material of the present invention, as described above, the crystal grain size of the brazing function-imparting sacrificial material of the aluminum alloy brazing sheet after brazing is 80 μm. As described above, it is preferably 100 μm or more. Due to this feature, as described above, the grain boundary portion is sufficiently reduced, and excellent corrosion resistance can be obtained.

6). Manufacturing Method of Heat Exchanger The heat exchanger is assembled by arranging fin materials on the outer surface of the tube material with both end portions attached to the header plate. Subsequently, the both ends overlapping part of the tube material, the fin material and the tube material outer surface, the both ends of the tube material and the header plate are simultaneously joined by one brazing heating. As the brazing method, a nocolok brazing method, a vacuum brazing method, or a fluxless brazing method is used. Brazing is usually performed by heating at a temperature of 590 to 610 ° C. for 2 to 10 minutes, preferably at a temperature of 590 to 610 ° C. for 2 to 6 minutes. The brazed one is usually cooled at a cooling rate of 20 to 500 ° C./min.

  Next, the present invention will be described in more detail based on examples, but the present invention is not limited thereto.

  The alloy for core materials having the alloy composition shown in Table 1, the alloy for brazing function imparting sacrificial material having the alloy composition shown in Table 2, the alloy for brazing material having the alloy composition shown in Table 3, and the alloy composition shown in Table 4 Each of the sacrificial anode material alloys was cast by DC casting, and the core material alloy was subjected to a homogenization treatment process at 600 ° C. for 3 hours, and then both surfaces were chamfered and finished. The thickness of the ingot after chamfering was 400 mm in all cases. For the brazing function-giving sacrificial material, brazing material and sacrificial anode material, both sides are chamfered, and the clad rate that is the target thickness is calculated by the final plate thickness, so that the thickness at the time of matching is required. Hot rolled to a predetermined thickness. Heating before hot rolling was performed at 520 ° C. for 3 hours.

  Using these alloys, a brazing-function sacrificial material is clad on one side of the core material alloy, and the other side is clad with nothing, or brazed on one side of the core material alloy. A three-layer clad material was produced by clad the function-giving sacrificial material and clad one of the brazing material, sacrificial anode material and brazing function-giving sacrificial material on the other surface.

  Next, the clad material was preheated at 480 ° C. for 3 hours and then subjected to a clad hot rolling step. In the clad hot rolling step, a rolling pass in which the rolling reduction in one pass was 30% or more was applied once or more while the temperature of the clad material was 250 ° C to 400 ° C. Table 5 shows the number of rolling passes. The plate thickness of the clad material at the end of the clad hot rolling process was 3.5 mm. The temperature of the clad material during the clad hot rolling process was measured for each rolling pass.

  After the clad hot rolling step, the clad material was subjected to a cold rolling step, and the plate thickness (final plate thickness) of the clad material at the end of the final cold rolling step was set to 0.5 mm to prepare an aluminum alloy brazing sheet sample. In the middle of the cold rolling process, the cladding material was subjected to the annealing process once or twice. The conditions for the first and second annealing were the same, and when the annealing process was performed twice, the total rolling reduction of the clad material from the first annealing to the second annealing was set to 30%. The said last cold rolling process means the cold rolling process after the last annealing process to the final board thickness among cold rolling processes. Table 5 shows the annealing conditions (temperature and time), the number of annealing steps, and the total reduction ratio of the clad material in the final cold rolling step. Table 5 shows manufacturing steps E1 to E13 from the clad hot rolling step to the final cold rolling step.

  The brazing material-provided sacrificial material clad on one surface of the core material alloy is the skin material 1, and the brazing material or sacrificial anode material clad on the other surface is the skin material 2. Tables 6 and 7 show the clad rates. The cladding rate of the skin material 2 was 15% in all cases. In Comparative Examples 19 to 34, the skin material 2 was not clad.

  In each manufacturing process of Table 5, when the final thickness of 0.3 mm could be rolled without any problem, the productivity was “◎” (excellent), and some cracks occurred during hot rolling. If the obtained case is "Good" (good), at least one of cracking during casting, uneven coating of the skin material, poor crimping between the core material and the skin material, cracking during hot rolling, uneven thickness of the plate, etc. When a good final product could not be obtained due to the occurrence of the problem, the manufacturability was “x” (defect). ◎ and ○ were accepted, and x was rejected. The results are shown in Tables 6 and 7.

  Each of the following evaluations was performed on the aluminum alloy brazing sheet sample produced as described above. In addition, since the sample was not able to be manufactured for those having the productivity “x” in Tables 6 and 7, the following evaluation could not be performed.

(Metal structure before brazing)
Without subjecting the brazing sheet sample to heating equivalent to brazing, the cross section was mirror-polished, subjected to Barker etching, and observed with a polarizing microscope. Whether the state of the metal structure of the skin material 1 and the core material is a fibrous structure or a recrystallized structure was determined. The results are shown in Tables 8-10.

(Tensile strength after brazing)
A brazing sheet sample subjected to a heat treatment at 600 ° C. for 3 minutes (corresponding to brazing additional heat) was subjected to a tensile test in accordance with JIS Z2241 under the conditions of a tensile speed of 10 mm / min and a gauge length of 50 mm. The tensile strength was read from the obtained stress-strain curve. As a result, the case where the tensile strength was 110 MPa or more was determined to be acceptable (◯), and the case where the tensile strength was less than that was rejected (x). The results are shown in Tables 8-10.

(Brazing)
Two brazing sheet samples were prepared for each example. In one sample, the skin material 1 serving as a test surface was masked, and the skin material 2 was removed by dipping in a 50 ° C. NaOH aqueous solution. Moreover, in the remaining sample, the skin material 2 used as a test surface was masked, and the skin material 1 was removed by being immersed in NaOH aqueous solution of 50 degreeC. When the skin material 2 is a sacrificial anode material, when the skin material 2 is not clad, and when a brazing sheet cannot be manufactured, only the skin material 1 is used as a test surface. Further, when both the skin materials 1 and 2 are brazing function imparting sacrificial materials, only the skin material 1 was used as a test surface. When the skin material 1 is a brazing function imparting sacrificial material and the skin material 2 is a brazing material, both the skin material 1 and the skin material 2 were used as test surfaces.
Next, 3003 alloy was corrugated to produce a fin material having 20 peaks. As shown in FIG. 2, two such brazing sheet samples were prepared, and the mini-core was manufactured by placing the fin material between the skin material 1 of one sample and the skin material 2 of the other sample. That is, when the skin material 1 and the skin material 2 are clad, there are 40 contacts between the brazing sheet sample and the fin material.

  The minicore was immersed in a 5% fluoride flux aqueous solution and subjected to brazing heat at 600 ° C. for 3 minutes. Next, the fins were peeled off from the mini-core, and the number of fillets formed at the contact points between the brazing sheet sample and the fins was defined as N, and the joining rate was determined as N / 40. When the joining rate was 95% or more and no melting occurred in the core material and the fin of the brazing sheet sample, the brazing property was determined to be acceptable (◯). In addition, when the fin bonding rate is less than 95%, when one or both of the core material and the fin of the brazing sheet sample are melted, and both of these cases, the brazing property is determined to be unacceptable (x). The results are shown in Tables 8-10.

(Crystal grain size of sacrificial material with brazing function after brazing)
The surface of the brazing function imparting sacrificial material surface of the brazing sheet sample subjected to heat treatment at 600 ° C. for 3 minutes (corresponding to brazing additional heat) is mirror-polished, and using SEM / EBSP (Electron Backscattering Diffraction Image Method), The crystal orientation of a 1 mm × 1 mm region was analyzed, and the crystal grain boundary was extracted from the obtained crystal orientation mapping. Note that an interface where grains having an orientation difference of 15 degrees or more are adjacent to each other was identified as a crystal grain boundary. The crystal grain boundary was transferred from the obtained image to a film sheet, and the equivalent circle diameter of the crystal grain was measured by image analysis. The case where the equivalent circle diameter was 80 μm or more was regarded as acceptable (◯), and the case where it was less than 80 μm was regarded as unacceptable (x). When the brazing function imparting sacrificial material was clad on both sides, only the skin material 1 was used as the test surface. The results are shown in Tables 8-10.

(Corrosion resistance)
The brazing sheet sample was heat treated at 600 ° C. for 3 minutes (corresponding to brazing additional heat), then cut into 50 mm × 50 mm, and the surface opposite to the test surface was masked with resin. When the test surface was a brazing material imparted with brazing function or a brazing material to which Zn was added, the test surface was subjected to the SWAAT test based on ASTM-G85, and was taken out after 500 hours and 1000 hours had elapsed. Thereafter, the corrosion product was washed with concentrated nitric acid, and when the penetration was confirmed by observing the surface of the test surface with a stereomicroscope, it was determined that there was penetration. The case where corrosion penetration did not occur in 1000 hours was regarded as excellent (◎), the corrosion penetration did not occur in 500 hours, but the corrosion penetration occurred in 1000 hours, (good), 500 hours In the case where corrosion penetration occurred, a defect (x) was determined. ◎ and ○ were accepted, and x was rejected.

On the other hand, ^when the test surface is a sacrificial ^{_{material, Cl - 500ppm, SO 4 2-}} 100ppm, 8 hours at a high temperature water of 88 ° C. containing Cu 2+ 10 ppm, the cycle immersion test in which one cycle stand at room temperature for 16 hours 3 The test was conducted for months, and no corrosion penetration occurred. In addition, corrosion resistance was not evaluated with respect to the brazing material to which Zn was not added. In addition, when the brazing function imparting sacrificial material was clad on both sides, only the skin material 1 was used as the test surface. The results are shown in Tables 8-10.

  In Examples 1 to 18 and 52 to 59 of the present invention, the conditions specified in the present invention were satisfied, and the crystal of the sacrificial material with brazing function after brazing, the tensile strength after brazing, the brazing property, and the brazing function. Both particle size and corrosion resistance were acceptable. Moreover, although the comparative examples 42 and 43 satisfy | fill the conditions prescribed | regulated by this invention about the core material and the brazing function provision sacrificial material, it is a pass, but the conditions which the brazing material which added Zn prescribed | regulated by this invention are satisfy | filled. It was not satisfied and its corrosion resistance was insufficient. Comparative Examples 45 to 51 satisfy the conditions specified in the present invention for the core material and the brazing function imparted sacrificial material, but the sacrificial anode material does not satisfy the conditions specified in the present invention. Corrosion resistance and manufacturability were unacceptable. On the other hand, in inventive examples 5 and 6, the corrosion resistance of the brazing filler metal surface to which Zn was added was also excellent. Moreover, about invention example 8-18, the corrosion resistance of the sacrificial anode material was also excellent.

In Comparative Example 19, since there was too much Si component in the core material, the core material melted during brazing, and the brazeability was unacceptable.
In Comparative Example 20, since there was too much Mg component of the core material, unbonded with the fin occurred, the fin bonding rate was low, and the brazing property was unacceptable.
In Comparative Example 21, since there was too much Fe component in the core material, brazing erosion of the core material occurred, the core material melted, and the brazeability was unacceptable.
In Comparative Example 22, since there were too many Ti, Cr, Zr and V components in the core material, cracks occurred during rolling, making it impossible to produce a brazing sheet, and the productivity was unacceptable.
In Comparative Example 23, since there was too much Mn component of the core material, cracking occurred during rolling, and a brazing sheet could not be produced, and the productivity was unacceptable.
In Comparative Example 24, since there were too many Cu components in the core material, cracks occurred during rolling, and a brazing sheet could not be produced, resulting in an unacceptable manufacturability.
In Comparative Example 25, since the Mn component of the core material was too small, the tensile strength after brazing was not acceptable.
In Comparative Example 26, since there was too little Si component of the brazing function imparting sacrificial material, unbonding with the fin occurred, the fin bonding rate was low, and the brazing property was unacceptable.
In Comparative Example 27, since there were too many Si components of the brazing function imparted sacrificial material, most of the brazing function imparted sacrificial material flowed during brazing, and the corrosion resistance was unacceptable.
In Comparative Example 28, since there were too many Fe components in the brazing function imparting sacrificial material, unbonding with the fins occurred, the fin bonding rate was low, and the brazing property was unacceptable.
In Comparative Example 29, since the Zn component of the brazing function imparting sacrificial material was too small, the sacrificial anticorrosion function was insufficient and the corrosion resistance was unacceptable.
In Comparative Example 30, since there were too many Zn components in the brazing function-imparting sacrificial material, the brazing function-giving sacrificial material disappeared early in the corrosion test, and the corrosion resistance was unacceptable.
In Comparative Example 31, since there were too many components of Ti, Cr, Zr and V in the brazing function imparting sacrificial material, cracking occurred during rolling, and the brazing sheet could not be produced, and the productivity was unacceptable. .
In Comparative Example 32, since there were too many Mn components of the brazing function imparting sacrificial material, cracking occurred during rolling, and a brazing sheet could not be produced, resulting in a failure in manufacturability.
In Comparative Example 33, since there were too many Na and Sr components in the brazing function imparting sacrificial material, unbonding with the fins occurred, the fin bonding rate was low, and the brazing property was unacceptable.
In comparative example 34, since there were too many Cu components of brazing function provision sacrificial material, sacrificial anticorrosion function was inadequate and corrosion resistance was unsuccessful.

In Comparative Example 35, since the Si component of the brazing material was too small, unbonded with the fins occurred, the fin bonding rate was low, and the brazing property was unacceptable.
In Comparative Example 36, since there was too much Si component in the brazing material, fins were melted during brazing, and the brazing property was unacceptable.
In Comparative Example 37, since there was too much Cu component in the brazing material, cracking occurred during rolling, and the brazing sheet could not be produced, and the productivity was unacceptable.
In Comparative Example 38, since there was too much Fe component in the brazing material, unbonding with the fins occurred, the fin bonding rate was low, and the brazing property was unacceptable.
In Comparative Example 39, since there were too many components of Ti, Cr, Zr and V in the brazing material, cracks occurred during rolling, and a brazing sheet could not be produced, resulting in an unacceptable manufacturability.
In Comparative Example 40, since there was too much Mn component in the brazing material, cracks occurred during rolling, and a brazing sheet could not be produced, resulting in an unacceptable manufacturability.
In Comparative Example 41, since there were too many Sr and Na components in the brazing material, unbonding with the fins occurred, the fin bonding rate was low, and the brazing property was unacceptable.
In Comparative Example 42, since the Zn component of the brazing material was too small, the sacrificial anticorrosion function was insufficient and the corrosion resistance was unacceptable.
In Comparative Example 43, since there was too much Zn component in the brazing material, the brazing material disappeared early in the corrosion test, and the corrosion resistance was unacceptable.
In Comparative Example 44, since there were too many Cu components in the brazing material, the sacrificial anticorrosion function was insufficient and the corrosion resistance was unacceptable.
In Comparative Example 45, since the sacrificial anode material contained too much Si, the sacrificial anticorrosion function was insufficient and the corrosion resistance was unacceptable.
In Comparative Example 46, since the Fe component of the sacrificial anode material was too much, the sacrificial anode material disappeared early in the corrosion test and the corrosion resistance was unacceptable.
In Comparative Example 47, since there were too many Ti, Cr, Zr, and V components of the sacrificial anode material, cracks occurred during rolling, and a brazing sheet could not be produced, resulting in an unacceptable manufacturability.
In Comparative Example 48, since there was too much Mn component of the sacrificial anode material, cracking occurred during rolling, and a brazing sheet could not be produced, resulting in an unacceptable manufacturability.
In Comparative Example 49, since the Zn component of the sacrificial anode material was too small, the sacrificial anticorrosion function was insufficient and the corrosion resistance was unacceptable.
In Comparative Example 50, since the Zn component of the sacrificial anode material was too much, the sacrificial anode material disappeared early in the corrosion test and the corrosion resistance was unacceptable.
In Comparative Example 51, since the Mg component of the sacrificial anode material was too much, it could not be pressure-bonded to the core material by clad hot rolling. Therefore, the brazing sheet could not be produced, and the productivity was unacceptable.

In Comparative Example 60, since the clad rate of the brazing function-giving sacrificial material was too low, the brazing function-giving sacrificial material could not be coated uniformly. Therefore, the brazing sheet could not be produced, and the productivity was unacceptable.
In Comparative Example 61, since the clad rate of the brazing function-giving sacrificial material was too high, the brazing function-giving sacrificial material before brazing was not a recrystallized structure, and the brazing function-giving sacrificial material after brazing was not The crystal grain size was less than 80 μm, and the corrosion resistance was unacceptable.
In Comparative Example 62, the number of passes with a rolling reduction of 30% or more was less than 2 passes while the material temperature during clad hot rolling was 250 ° C to 400 ° C. Therefore, the brazing function imparted sacrificial material before brazing did not have a recrystallized structure, and the brazing function imparted sacrificial material after brazing had a crystal grain size of less than 80 μm, and the corrosion resistance was unacceptable.
In Comparative Example 63, since the annealing temperature was too low, the brazing function-imparting sacrificial material before brazing was not recrystallized, and the crystal grain size of the brazing function-giving sacrificial material after brazing was less than 80 μm. The corrosion resistance was unacceptable.
In Comparative Example 64, since the annealing temperature was too high, the core material before brazing was not a fibrous structure, and brazing erosion occurred during brazing. Therefore, unbonding with the fin occurs, the fin bonding rate is lowered, and the brazability is unacceptable.
In Comparative Example 65, since the annealing time was too short, the brazing function-imparting sacrificial material before brazing was not recrystallized, and the brazing function-giving sacrificial material after brazing was less than 80 μm. The corrosion resistance was unacceptable.
In Comparative Example 66, the total rolling reduction in the final cold rolling process was too high, so that the crystal grain size of the brazing function imparted sacrificial material after brazing was less than 80 μm, and the corrosion resistance was unacceptable.
In Comparative Example 67, since the total rolling reduction in the final cold rolling process was too low, the rolling became unstable. For this reason, a brazing sheet having a target thickness cannot be produced, and the manufacturability is unacceptable.

In addition, the reference examples 68-70 of Table 10 are manufactured on the manufacturing conditions shown to E14-16 of Table 5. In these examples, the brazing sheet could not be produced because the heating conditions before hot clad rolling were inappropriate.
That is, in Reference Example 68, since the heating temperature was too low, cracking occurred during hot clad rolling, and a brazing sheet having a target thickness could not be produced.
In Reference Example 69, since the heating time was too short, cracks occurred during hot clad rolling, and a brazing sheet having a target thickness could not be produced.
In Reference Example 70, since the heating temperature was too high, the brazing function-giving sacrificial material was melted, and a brazing sheet having a target thickness could not be manufactured.

  The aluminum alloy brazing sheet according to the present invention has a high strength after brazing and is excellent in brazing and corrosion resistance such as a fin joint ratio and erosion resistance, and is particularly suitable as a flow path forming component of an automotive heat exchanger. Used for.

Claims (13)

  In an aluminum alloy brazing sheet comprising an aluminum alloy core material and a brazing function-imparting sacrificial material clad on at least one surface of the core material, the core material comprises Si: 0.05 to 1.2 mass%, Fe:. It consists of an aluminum alloy containing 05-1.2 mass%, Mn: 0.5-2.0 mass%, the balance being Al and inevitable impurities, and the brazing function imparting sacrificial material is Si: 2.5-7 0.0 mass%, Zn: 0.5-8.0 mass%, Fe: 0.05-1.2 mass%, consisting of an aluminum alloy consisting of the balance Al and unavoidable impurities, The clad rate is 3 to 25%, and the metal structure before brazing heat of the core material is a fibrous structure, and the brazing function-imparting sacrificial material is brazed. Aluminum alloy brazing sheet, characterized in that the metal structure before it is recrystallized structure.   In an aluminum alloy brazing sheet comprising an aluminum alloy core material, a brazing function imparting sacrificial material clad on one surface of the core material, and a brazing material clad on the other surface of the core material, the core material is Si: 0. 0.05 to 1.2 mass%, Fe: 0.05 to 1.2 mass%, Mn: 0.5 to 2.0 mass%, comprising an aluminum alloy composed of the balance Al and inevitable impurities, the brazing function The sacrifice sacrificial material contains Si: 2.5-7.0 mass%, Zn: 0.5-8.0 mass%, Fe: 0.05-1.2 mass%, and the balance aluminum and unavoidable impurities It is made of an alloy, and the brazing material contains Si: 2.5 to 13.0 mass%, Fe: 0.05 to 1.2 mass%, the balance Al and inevitable impurities The clad rate of the brazing function-imparting sacrificial material is 3 to 25%, the metal structure of the core material before brazing heat is a fibrous structure, An aluminum alloy brazing sheet characterized in that the metal structure before brazing heat is a recrystallized structure.   In an aluminum alloy brazing sheet comprising an aluminum alloy core material, a brazing function imparting sacrificial material clad on one surface of the core material, and a brazing material clad on the other surface of the core material, the core material is Si: 0. 0.05 to 1.2 mass%, Fe: 0.05 to 1.2 mass%, Mn: 0.5 to 2.0 mass%, comprising an aluminum alloy composed of the balance Al and inevitable impurities, the brazing function The sacrifice sacrificial material contains Si: 2.5-7.0 mass%, Zn: 0.5-8.0 mass%, Fe: 0.05-1.2 mass%, and the balance aluminum and unavoidable impurities It is made of an alloy, and the brazing material contains Si: 7.1 to 13.0 mass%, Fe: 0.05 to 1.2 mass%, Zn: 0.5 to 8.0%, The brazing function-giving sacrificial material has a cladding ratio of 3 to 25%, and the metal structure before the brazing heat of the core material is a fibrous structure. An aluminum alloy brazing sheet, characterized in that the metallographic structure of the sacrificial material having a functional function before the brazing heat is a recrystallized structure.   In an aluminum alloy brazing sheet comprising an aluminum alloy core material, a brazing function-imparting sacrificial material clad on one surface of the core material, and a sacrificial anode material clad on the other surface of the core material, the core material is made of Si. : 0.05-1.2 mass%, Fe: 0.05-1.2 mass%, Mn: 0.5-2.0 mass%, comprising the balance Al and unavoidable impurities, an aluminum alloy, The functionalized sacrificial material contains Si: 2.5 to 7.0 mass%, Zn: 0.5 to 8.0 mass%, Fe: 0.05 to 1.2 mass%, and the balance Al and unavoidable impurities. The sacrificial anode material is made of Zn: 0.5 to 8.0 mass%, Si: 0.05 to 1.5 mass%, Fe 0.05 to 2.0 mass. Is made of an aluminum alloy composed of the balance Al and inevitable impurities, the cladding rate of the brazing function imparting sacrificial material is 3 to 25%, and the metal structure of the core material before brazing heat is a fibrous structure An aluminum alloy brazing sheet, wherein the brazing function imparting sacrificial material has a recrystallized metal structure before brazing heat.   The core material is Cu: 0.05 to 1.2 mass%, Mg: 0.05 to 0.5 mass%, Ti: 0.05 to 0.3 mass%, Zr: 0.05 to 0.3 mass%, Cr: It consists of an aluminum alloy which further contains 1 type, or 2 or more types selected from 0.05-0.3 mass% and V: 0.05-0.3 mass%, It is any one of Claims 1-4. Aluminum alloy brazing sheet.   The sacrificial material with brazing function is Cu: 0.05-0.5 mass%, Mn: 0.05-2.0 mass%, Ti: 0.05-0.3 mass%, Zr: 0.05-0. 3 mass%, Cr: 0.05-0.3 mass%, V: 0.05-0.3 mass%, Na: 0.001-0.05 mass% and Sr: 0.001-0.05 mass% The aluminum alloy brazing sheet according to any one of claims 1 to 5, comprising an aluminum alloy further containing one or more kinds.   The brazing material is Cu: 0.05 to 1.2 mass%, Mn: 0.05 to 2.0 mass%, Ti: 0.05 to 0.3 mass%, Zr: 0.05 to 0.3 mass%, Cr : 0.05 to 0.3 mass%, V: 0.05 to 0.3 mass%, Na: 0.001 to 0.05 mass%, and Sr: 0.001 to 0.05%, or one or two selected The aluminum alloy brazing sheet according to any one of claims 2, 5, and 6, further comprising an aluminum alloy further containing seeds.   The brazing material is Cu: 0.05-0.5 mass%, Mn: 0.05-2.0 mass%, Ti: 0.05-0.3 mass%, Zr: 0.05-0.3 mass%, Cr : 0.05 to 0.3 mass%, V: 0.05 to 0.3 mass%, Na: 0.001 to 0.05 mass%, and Sr: 0.001 to 0.05%, or one or two selected The aluminum alloy brazing sheet according to any one of claims 3, 5 and 6, further comprising an aluminum alloy further containing seeds.   The sacrificial anode material is Mn: 0.05 to 2.0 mass%, Mg: 0.5 to 3.0 mass%, Ti: 0.05 to 0.3 mass%, Zr: 0.05 to 0.3 mass%, 7. The aluminum alloy according to claim 4, further comprising one or more selected from Cr: 0.05 to 0.3 mass% and V: 0.05 to 0.3 mass%. The aluminum alloy brazing sheet according to one item.   It is a manufacturing method of the aluminum alloy brazing sheet as described in any one of Claims 1, 5, and 6, Comprising: The process which casts the aluminum alloy for the said core material and brazing function provision sacrificial material, respectively, and a core material ingot A clad step of clad a brazing function-giving sacrificial material having a predetermined thickness on at least one surface thereof, a hot-clad step of clad hot-rolling the clad material, and cooling the hot-rolled clad material Including a cold rolling step for cold rolling and one or more annealing steps for annealing the clad material in the middle of the cold rolling step, and the temperature of the clad material is 250 to 400 ° C. in the clad hot rolling step. Including two or more rolling passes in which the rolling reduction rate in one pass is 30% or more, and the clad material is held at 200 to 300 ° C. for 1 to 10 hours in the final annealing step Is, an aluminum alloy brazing sheet manufacturing method, which comprises a total rolling reduction of the clad material in the last subsequent annealing step the final cold rolling step 5 to 25%.   It is a manufacturing method of the aluminum alloy brazing sheet as described in any one of Claims 2, 3, and 5-8, Comprising: The aluminum alloy for the said core material, the brazing function provision sacrificial material, and the brazing material is respectively casted. A clad step in which a brazing function-giving sacrificial material having a predetermined thickness is clad on one surface of the core material ingot and a brazing material having a predetermined thickness is clad on the other surface to form a clad material; Including a hot rolling clad hot rolling process, a cold rolling process for cold rolling the hot rolled clad material, and one or more annealing processes for annealing the clad material in the middle of the cold rolling process, In the hot rolling process of the clad, the rolling material includes a rolling pass in which the reduction rate in one pass is 30% or more while the temperature of the clad material is 250 to 400 ° C., and in the final annealing step The clad material is held at 200 to 300 ° C. for 1 to 10 hours, and the total rolling reduction ratio of the clad material in the final cold rolling step following the last annealing step is 5% to 25%. Sheet manufacturing method.   It is a manufacturing method of the aluminum alloy brazing sheet as described in any one of Claim 4, 5, 6, and 9, Comprising: The aluminum alloy for the said core material, brazing function provision sacrificial material, and sacrificial anode material is cast, respectively. A cladding step of cladding a brazing function-giving sacrificial material having a predetermined thickness on one surface of the core material ingot, and cladding a sacrificial anode material having a predetermined thickness on the other surface; A clad hot rolling step for hot rolling the clad material, a cold rolling step for cold rolling the hot rolled clad material, and one or more annealing steps for annealing the clad material during the cold rolling step; In the clad hot rolling step, the final annealing process includes two or more rolling passes in which the reduction rate in one pass is 30% or more while the temperature of the clad material is 250 to 400 ° C. In which the clad material is held at 200 to 300 ° C. for 1 to 10 hours, and the total reduction ratio of the clad material in the final cold rolling step following the last annealing step is 5% to 25% An alloy brazing sheet manufacturing method.   A heat exchanger using the aluminum alloy brazing sheet according to any one of claims 1 to 9, wherein the brazing function-imparting sacrificial material after brazing has a crystal grain size of 80 µm or more. Heat exchanger.

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