KR20150127875A - High strength clad material having good sag resistance and sacrificed protection property and producing method for the same - Google Patents

Abstract

The present invention relates to a clad material for brazing which can be suitably used as a heat exchanger material for automobiles such as a radiator, a condenser, a heater, an evaporator and an intercooler, which is excellent in strength and light weight and excellent in sag resistance and erosion resistance .
The brazing clad material for brazing according to the present invention is characterized in that the brazing material for brazing is composed of 0.30 to 0.50 wt% of silicon (Si), 0.35 to 0.55 wt% of iron (Fe), 1.15 to 1.50 wt% of manganese (Mn), 0.70 to 1.50 wt% of zinc Zn) and 0.02 to 0.25% by weight of titanium (Ti), the remaining aluminum (Al) and an aluminum alloy containing unavoidable impurities, and a core material which is clad on one or both surfaces of the core material and contains silicon And the like.

Description

TECHNICAL FIELD [0001] The present invention relates to a high-strength clad material for brazing excellent in sag resistance and sacrificial corrosion resistance, and a method for producing the clad material.

The present invention relates to a clad material which can be used for a heat exchanger, and more particularly, to a clad material which is excellent in strength and can be reduced in weight, has a sag resistance and a sacrificial anticorrosion property (a property to prevent corrosion of a contact material to be contacted) To a clad material for brazing which can be suitably used as an automotive heat exchanger material such as a condenser, a heater, an evaporator, and an intercooler, and a method of manufacturing the same.

Aluminum alloy is used as heat exchanger material for automobile such as radiator, condenser, heater, evaporator, intercooler and so on since it has high thermal conductivity and high rigidity. In particular, vacuum brazing and flux brazing process of 1970s have been developed and various heat exchanger parts Aluminum alloy and aluminum clad plate for brazing are applied.

The aluminum clad material for double brazing is applied to parts such as tubes, headers, supports, and pins according to the type of heat exchanger, and is structurally made of an Al-Si alloy having a low melting point which is melted during brazing to give bonding force And a core made of an Al-Mn-based alloy in consideration of mechanical properties, brazing property, and corrosion resistance are cladded.

The aluminum alloy heat exchanger manufactured by brazing is mainly composed of a fin formed in a wavy pattern for heat dissipation and a tube for circulating the refrigerant.

When the double tube is penetrated by corrosion or fracture, the refrigerant circulating inside is leaked. Therefore, in order to prolong the life of the product, an aluminum alloy material excellent in strength and corrosion resistance after brazing is indispensable.

In recent years, there has been a growing demand for lightweight automobiles, and in order to cope with this, weight reduction of automotive heat exchangers is also required. As a result, there is an increasing need to form the respective members constituting the heat exchanger to be thinner.

Conventionally, as a tube material of a heat exchanger in which cooling water circulates on the inner surface of a tube such as a radiator or a heater for an automobile, an Al-Zn based alloy such as an Al-Mn based alloy represented by JIS 3003 alloy, A triple-layered tube material in which a sacrificial anode material such as an alloy is clad and a brazing filler metal such as an Al-Si alloy is clad at the air side has been generally used.

The core material made of JIS 3003 alloy has the composition shown in Table 1 below. The core material made of JIS 3003 alloy has a strength of only about 110 MPa after the brazing process performed at about 600 ° C. Not full yet.

Alloy name Measurement method Composition (% by weight) Si Fe Cu Mn Zn A3003 Specifications Less than 0.6 Less than 0.7 0.05 to 0.20 1.0 to 1.5 Less than 0.10 ICP 0.37 0.49 0.15 1.13 0.03

Accordingly, in the following patent documents 1 and 2, a three-layered clad tube material using aluminum in which Mg is added to the core material is proposed in order to improve the strength after brazing.

As described above, Mg may be added to the core material to improve the strength. However, since the fluoride-based flux used in the Nocolock Brazing reacts with Mg to form a compound such as MgF 2, .

The following Patent Document 3 discloses an "method for producing an aluminum alloy brazing sheet ", which is manufactured by casting a core material, an intermediate material and an aluminum alloy for a sacrificial anode material to prepare a core material, an intermediate material and a sacrificial cathode material, homogenizing the material, .

According to this method, when an alloy containing a large amount of alloying elements is used, the unevenness of the cast structure is increased to increase the occurrence of defects in rolling joining and subsequent rolling, and it is required to be manufactured through many rolling processes. Is required.

In the following Patent Document 4, there is proposed a method of significantly reducing the number of rolling processes by casting core material and substrate by roll casting, roll bonding and cladding. According to this method, a high strength clad sheet can be obtained while minimizing the rolling process, . ≪ / RTI >

On the other hand, the above-mentioned clad sheet material should be capable of preventing physical property degradation due to diffusion of Si elements and formation of a compound due to melting of the substrate during brazing in addition to high strength, and good sag resistance property and erosion resistance property are also required.

However, the alloy composition of the core disclosed in the following Patent Document 4 has a limitation in meeting all requirements for excellent strength, sacrifice and sag resistance.

1. JP-A-8-246117 2. Japanese Patent Application Laid-Open No. 2003-55727 3. Korean Published Patent Application No. 2007-0061413 4. Korean Patent Publication No. 2012-0114731

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the conventional cladding material for brazing, and it is an object of the present invention to provide a high-strength cladding material for brazing having a high sag resistance as well as high sag resistance, And to provide a heat exchanger.

Another object of the present invention is to provide a method for producing a high-strength clad material for brazing, which has not only high strength but also good sag resistance and sacrificial virility.

According to an aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: a step of forming a silicon carbide layer containing 0.30-0.50 wt% silicon, 0.35-0.55 wt% Fe, 1.15-1.50 wt% manganese, Core material comprising aluminum (Al) and unavoidable impurities, the core being composed of zinc (Zn) in an amount of 0.02 to 0.25% by weight and titanium (Ti) in an amount of 0.02 to 0.25% Strength clad material for brazing comprising an object made of an aluminum alloy containing silicon (Si).

According to another aspect of the present invention, there is provided a heat exchanger including the fin material formed by molding the above clad material.

In another aspect of the present invention, there is provided a method of manufacturing a semiconductor device, the method including the steps of: 0.30-0.50 wt% silicon; 0.35-0.55 wt% iron; 1.15-1.50 wt% manganese; (Si), aluminum (Al) and aluminum (Al) containing silicon (Si) in an amount of 0.02 to 0.25% by weight, A step of subjecting the core material and the workpiece to a homogenization treatment and cold-rolling the homogenized workpiece, a step of surface-treating the joint surface of the core material and the workpiece, And laminating and joining the objects so that the joint surfaces are in contact with each other on both sides.

The cladding material according to the present invention has excellent tensile strength and sag resistance as well as superior sacrificial corrosion resistance through addition of titanium (Ti), chromium (Cr), zirconium (Zr) and copper Thereby providing a clad material particularly suitable for the fin material of the heat exchanger.

In addition, since the cladding is formed by rolling and joining the core material and the fin material after the core material and the fin material are laminated, the process cost and the energy cost for manufacturing the high-strength clad material for brazing can be remarkably reduced .

Fig. 1 is a process diagram schematically showing the manufacture of a high-strength clad plate for brazing according to an embodiment of the present invention, the manufacture of a fin material for a heat exchanger using the clad plate material, and a manufacturing process of the heat exchanger.
2 schematically shows a method for evaluating sag resistance.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the following embodiments of the present invention may be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. Embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art.

The present inventors have found that, in a clad material made of an Al-Mn alloy and an Al-Si alloy, it is possible to provide a clad material having a moldability sufficient to meet the properties required for a heat exchanger fin, a high sacrificial corrosion resistance and a good sag resistance, The present inventors have found that the above-described characteristics can be realized by designing an Al-Mn-based aluminum alloy as a clad material. As a result, the present invention has been accomplished.

The clad material according to the present invention is a clad material which comprises 0.30 to 0.50% by weight of silicon (Si), 0.35 to 0.55% by weight of iron, 1.15 to 1.50% by weight of manganese Mn, 0.70 to 1.50% And an aluminum alloy containing 0.02 to 0.25% by weight of titanium (Ti), the balance being aluminum (Al) and an aluminum alloy containing unavoidable impurities, and an aluminum alloy containing silicon (Si) on one surface or both surfaces of the core material. And a structure made of an alloy is bonded.

At this time, the core material may further include at least one selected from 0.07 to 0.25 weight% of chromium (Cr) and 0.07 to 0.25 weight% of zirconium (Zr).

In addition, the core may further contain 0.20 to 0.35% by weight of copper (Cu), wherein the content of titanium (Ti) is preferably 0.07 to 0.13% by weight.

In addition, the substrate may include 6.8 to 8.2% by weight of silicon (Si).

First, the reason why the composition of the alloy element contained in the core material is limited as described above will be described.

Silicon (Si) functions to increase strength by forming a strengthened phase such as an AlMnSi compound or an AlFeMnSi compound by bonding with an element such as aluminum (Al), manganese (Mn), iron (Fe) It is difficult to obtain the effect of improving the strength because it is difficult to obtain the effect of improving the strength. When the amount of the additive is more than 0.50% by weight, the Si single phase is easily formed, Do.

Iron (Fe) binds with elements such as aluminum (Al), manganese (Mn) and silicon (Si) to form an AlFeMnSi compound strengthened phase to increase the strength. When added at less than 0.35 wt% The strengthened phase is not sufficiently formed and it is difficult to obtain the effect of improving the strength. When it is added in an amount exceeding 0.55% by weight, a coarse AlFeSi phase is formed to cause brittleness, so that it is preferably 0.35-0.55% by weight.

Manganese (Mn) combines with elements such as aluminum (Al), iron (Fe) and silicon (Si) to form a dispersion strengthening phase to improve strength. When Mn is added at less than 1.15 wt% -Fe phase, or the Al-Mn strengthened phase fraction is lowered, so that sufficient strength improvement is difficult to be achieved. When the amount of the strengthening phase is more than 1.50 wt%, the size of the strengthening phase is increased, It is disadvantageous in the rolling process, and therefore, it is preferably 1.15 to 1.50% by weight.

Zinc (Zn) is an element which enhances solid solution strengthening and lowering the corrosion potential of the core to enhance the sacrificial anode function. For example, when it is applied to a fin, , The effect of lowering the corrosion potential is not sufficient. When it is added in an amount exceeding 1.50% by weight, the corrosion potential is excessively lowered and the corrosion is abruptly generated, so that it is preferably 0.70 to 1.50% by weight.

Titanium (Ti) is an element which suppresses segregation through grain refinement during casting and binds with aluminum and silicon elements to form a high-temperature steady state, thereby preventing the strength from being lowered at high temperature exposure, and less than 0.02 wt% , The effect of grain refinement is low and the formation of a stable high-temperature state is not sufficient. If it is added in an amount exceeding 0.25% by weight, an acicular Al-Ti compound is formed to induce embrittlement, so that it is preferably 0.02 to 0.25% by weight.

Copper (Cu) can be selectively added to an element that acts as a solid solution solid solution in an aluminum matrix, and when added at less than 0.20 wt%, Cu is not sufficient to obtain a solid solution strengthening effect, and addition of more than 0.35 wt% , The corrosion potential is lowered and the effect of the sacrificial anode is reduced. When it is used for the fin material, corrosion of the tube is caused, so that it is preferably 0.20 to 0.35 wt%. If zinc (Zr) or chromium (Cr) is not added together when copper (Cu) is added, it is preferable that the content of titanium (Ti) is 0.07-0.13 wt% If it is out of the range, the sacrificial system property may deteriorate.

Cr (Cr) can be selectively added as an element which plays a role of improving the sag characteristic by suppressing the decrease in strength at the time of high-temperature exposure by forming an Al-Cr compound as a high-temperature stable phase, Is not sufficient to suppress deterioration of high-temperature strength, and when it is added in an amount exceeding 0.25% by weight, a coarse Al-Cr compound is formed to induce brittleness, so that it is preferably 0.07 to 0.25% by weight. Particularly, it is more preferable that chromium (Cr) is added in the range of 0.07 to 0.13% by weight in terms of sag characteristics.

The zirconium (Zr) can be selectively added to an element which plays a role of improving the sag characteristic by suppressing the decrease of the strength at the time of high temperature exposure by forming the Al-Zr compound, which is a high temperature stable phase. It is not sufficient to suppress the deterioration of high-temperature strength, and when added in an amount exceeding 0.25% by weight, the sag property sharply decreases, and therefore, it is preferably 0.02 to 0.25% by weight.

The content of silicon (Si) contained in the substrate is not particularly limited as long as it is at a level capable of providing a bonding force by melting at a brazing temperature. When the content is less than 6.8 wt%, the core material melts due to a rise in the melting temperature, , And when it is more than 8.2% by weight, it is preferable that it is included in the amount of 6.8 to 8.2% by weight because erosion into the core material may occur due to the lowering of the melting temperature and the excessive silicon (Si) content in the brazing operation.

The inevitable impurities are elements that are unintentionally incorporated from raw materials and facilities in the course of manufacturing an aluminum alloy, and are elements that must be managed so as to be contained within a range that does not significantly affect the function of the core or the substrate. At this time, the content of the impurities is set to 1% by weight or less, preferably 0.1% by weight or less, more preferably 0.01% by weight or less.

In addition, the tensile strength after brazing of the clad material may be 160 MPa or more, the sag distance of the clad material may be 30 mm or less, and the corrosion potential of the clad material may be lower than -770 mV.

FIG. 1 is a process diagram schematically showing a manufacturing process of a high-strength clad plate for brazing according to the present invention, a manufacturing process of a fin material for a heat exchanger using the clad plate material, and a manufacturing process of the heat exchanger.

As shown in FIG. 1, the manufacturing process of the high-strength clad plate for brazing according to the present invention includes a step (S100) of preparing a core material and a workpiece having the above-described alloy composition, a step S200 of homogenizing the core material and the workpiece (S300) of controlling the thickness by cold-rolling the homogenized workpiece, and cladding the core and the workpiece (S400).

In the step of preparing the core material and the image material (S100), the core material and the image material may be formed of a plate material by hot rolling, cold rolling or the like from an ingot of an alloy having the above composition. However, when a thin plate material such as a fin material of a heat exchanger is required, a thin plate-like cast material can be obtained by applying the thin plate casting method, so that the number of rolling processes can be significantly reduced But is more preferable because uniform microstructure can be obtained. The thin plate casting can be performed by a known twin roll casting method to obtain a thin plate material having a thickness of about 4 to 8 mm, and in the embodiment of the present invention, a plate casted to about 4 mm is used .

Preferably, the step of homogenizing the core material and the object (S200) is for homogenizing the uneven structure produced by the casting, and the homogenizing treatment is preferably performed for 1 to 24 hours at a temperature of 400 to 500 ° C, If the homogenization treatment temperature is lower than 400 ° C, component segregation in the thickness direction of the plate material may occur and the cast structure may be maintained. If the homogenization treatment temperature is higher than 500 ° C, the production cost may be increased due to excessive energy consumption, If the time is less than 1 hour, microstructure nonuniformity of the surface / inside and outside / inside diameter parts of the casting plate and coil unit is caused, and if it exceeds 24 hours, the production cost becomes high due to excessive energy consumption. A more preferable homogenization treatment is performed at 420 to 480 DEG C for 8 to 24 hours.

The step of cold-rolling the work (S300) is a step for adjusting the thickness of the work to meet the target cladding thickness, and the reduction rate in this step can be performed according to the thickness of the required core and the work. If necessary, the core material can also be subjected to cold rolling, and if it is formed to be very thin by thin sheet casting, the cold rolling process may be omitted.

The cladding step (S400) is a step of laminating a substrate on one side or both sides of a core material and then joining the same. The surface of the core material and the substrate are subjected to a surface treatment such as wire brushing, roll bonding, and the like.

As shown in FIG. 1, the clad material thus produced is subjected to a cold rolling step (S500), an intermediate annealing step (S600), a cold rolling step (S700) and a corrugation step (S800) And is manufactured as a fin material.

The cold rolling step S500 or S600 is a step for reducing the thickness of the clad material to a thin thickness required in the heat exchanger. The intermediate annealing step S600 is a step for forming a work hardening Is a heat treatment process for releasing the state that has been formed. The number of passes and the reduction rate per pass in the cold rolling process can be variously adjusted according to the characteristics of the clad material and finally required thickness and physical properties, and the intermediate annealing process (S600) Can be performed more than two times.

In the intermediate annealing step (S600), it is preferable that the clad material obtained by bonding the core material to the substrate is treated at a temperature of 400 to 500 DEG C for 8 to 24 hours, which is not annealed within the temperature and time range , The sag characteristic of the finally obtained clad material may be deteriorated.

In the cold rolling step (S700), the final rolling reduction is preferably performed at a final rolling reduction rate of 30 to 50%. If the reduction rate is not maintained, the sagging characteristic may be lowered Because.

The corrugation step S800 is a step of alternately bending the clad material processed by the thin plate material so as to have a wave pattern. The corrugation process can be performed through a general bending machine.

The fin material manufactured through the above process is joined to the tube material through the brazing process (S900) to form a heat exchanger. The brazing step (S900) using the clad material according to the present invention is preferably performed at 600 to 620 deg. C for 5 to 15 minutes. If the brazing temperature is less than 600 deg. C, the melting of the substrate is insufficient, If the brazing temperature is higher than 620 ° C, the core material is melted and excessively eroded. If the brazing time is less than 5 minutes, the material does not melt sufficiently to join the brazing material. If the brazing time is longer than 15 minutes, .

[Example 1]

An aluminum alloy consisting of 0.40% of silicon (Si), 0.52% of iron (Fe), 1.43% of manganese (Mn), 0.81% of zinc (Zn), 0.027% of titanium and the balance aluminum, And a core material was prepared by casting a plate material having a thickness of 4 mm.

Further, a JIS 4334 aluminum alloy containing silicon (Si) was thin-cast by a double-roll casting method to prepare a plate material having a thickness of 4 mm to prepare a filler material. As a result of analyzing the composition of JIS 4343 aluminum alloy used in the examples of the present invention Were as shown in Table 2 below.

Alloy name Measurement method Composition (% by weight) Si Fe Cu Mn Zn Mg Ti JIS 4343 Specifications 6.8 to 8.2 0.8
under 0.25
under 0.1
under 0.10
under - 0.03
under ICP 0.37 0.49 0.15 1.13 0.03 - 0.025

The thus prepared core material and workpiece were homogenized at 450 캜 for 1 hour.

The homogenized material was subjected to cold rolling a plurality of times at a reduction ratio of about 10% per pass under non-lubrication conditions, to an initial thickness of 4 mm to a thickness of 0.5 mm, followed by annealing at 450 캜 for 1 hour .

The bonding surfaces of the annealed core and the substrate were subjected to wire brushing treatment. On the other hand, in the embodiment of the present invention, the wire brushing is performed by surface treatment of the joint surface of the core and the substrate, but known surface treatment such as sandblasting or chemical treatment may be performed.

Roll-bonding was performed by performing two steps of non-lubrication cold rolling at a reduction ratio of about 50% after disposing two substrates of 0.5 mm thickness on both sides of the core of 4 mm thickness, mm clad material. On the other hand, in the embodiment of the present invention, although the reduction ratio is set to 50% at the rolling joining, joining is possible through about one round of cold rolling at a reduction ratio of 40 to 70%.

The cold-rolled clad material was subjected to an intermediate annealing treatment at 450 ° C for 14 hours to soften the microstructure of the work-hardened clad material through the cold rolling.

The intermediate annealed clad material was further cold-rolled under the condition of a final reduction ratio of 38.5% to prepare a plate having a thickness of 0.08 mm suitable for a fin material for a heat exchanger.

[Example 2]

Example 2 is different from Example 1 in that 0.38% of silicon, 0.52% of iron, 1.25% of manganese (Mn), 1.13% of zinc (Zn), 0.096% of titanium (Ti) A 0.08 mm thick clad plate was manufactured through the same process except that a core material was used to produce a plate material having a thickness of 4 mm by casting an aluminum alloy made of the remaining aluminum by a double roll casting method.

[Example 3]

Example 3 was prepared in the same manner as in Example 1 except that 0.38% of silicon (Si), 0.54% of iron (Fe), 1.25% of manganese (Mn), 1.17% of zinc (Zn), 0.17% 0.08 mm thick clad sheet material was manufactured through the same process except that a core material in which a 4 mm-thick plate was manufactured by thin-casting an aluminum alloy made of the remaining aluminum by a double-roll casting method.

[Example 4]

Example 4 is different from Example 1 in that 0.38% of silicon (Si), 0.54% of iron (Fe), 1.24% of manganese (Mn), 1.41% of zinc (Zn), 0.028% of titanium (Ti) A 0.08 mm thick clad sheet material was manufactured through the same process except that 0.088% of zirconium (Zr) and an aluminum alloy of the remaining aluminum were thin-cast by a double-roll casting method to produce a 4 mm thick plate.

[Example 5]

Example 5 was prepared in the same manner as in Example 1 except that 0.38% of silicon (Si), 0.51% of iron (Fe), 1.24% of manganese (Mn), 1.15% of zinc (Zn), 0.030% of titanium A clad plate of 0.08 mm in thickness was manufactured through the same process except that 0.11% of chromium (Cr) and an aluminum alloy of the remaining aluminum were thin-cast using a double-roll casting method to produce a plate material having a thickness of 4 mm.

[Example 6]

Example 6 was prepared in the same manner as in Example 1 except that 0.40% of silicon (Si), 0.54% of iron (Fe), 1.26% of manganese (Mn), 0.81% of zinc, 0.027% of titanium (Ti) 0.18% of chromium (Cr), and an aluminum alloy consisting of the remaining aluminum were thin-cast by a double-roll casting method to produce a plate material having a thickness of 4 mm, thereby producing a clad plate having a thickness of 0.08 mm.

[Example 7]

Example 7 shows a comparison between Example 1 and Comparative Example 1 in which 0.37% of silicon (Si), 0.52% of iron (Fe), 1.22% of manganese (Mn), 1.41% of zinc (Zn), 0.088% of titanium (Ti) A clad plate of 0.08 mm in thickness was produced through the same process except that 0.25% of copper (Cu) and an aluminum alloy of the remaining aluminum were thin-cast by a double-roll casting method to produce a plate material having a thickness of 4 mm.

[Example 8]

Example 8 was prepared in the same manner as in Example 1 except that 0.37% of silicon (Si), 0.53% of iron (Fe), 1.24% of manganese (Mn), 1.34% of zinc, 0.032% of titanium (Ti) A core material in which a plate material having a thickness of 4 mm was produced by thin casting an aluminum alloy consisting of 0.25% of copper (Cu), 0.091% of zirconium (Zr) and the remaining aluminum by the double roll casting method was used and the cold- A 0.08 mm thick clad sheet was produced through the same process except that the intermediate annealing treatment was performed for a period of time.

[Example 9]

Example 9 is different from Example 1 in that 0.38% of silicon, 0.50% of iron, 1.25% of manganese (Mn), 0.84% of zinc (Zn), 0.029% of titanium (Ti) Except that a core material in which a plate material having a thickness of 4 mm was produced by thin casting an aluminum alloy consisting of 0.25% of copper (Cu), 0.11% of chromium (Cr) and the remaining aluminum by the double-roll casting method was used, .

[Comparative Example 1]

Comparative Example 1 was prepared in the same manner as in Example 1 except that 0.39% of silicon (Si), 0.56% of iron (Fe), 1.43% of manganese (Mn), 0.84% of zinc (Zn), 0.027% of titanium A clad plate of 0.08 mm in thickness was manufactured through the same process except that 0.29% of copper (Cu) and an aluminum alloy made of the remaining aluminum were thin-cast by a double-roll casting method to produce a plate material having a thickness of 4 mm.

[Comparative Example 2]

Comparative Example 2 was prepared in the same manner as in Example 1 except that 0.38% of silicon (Si), 0.53% of iron (Fe), 1.25% of manganese (Mn), 0.82% of zinc, 0.027% of titanium (Ti) 0.18% of zirconium (Zr) and an aluminum alloy of the remaining aluminum were thin-cast by a double-roll casting method to produce a plate material having a thickness of 4 mm. The cold-rolled clad material was subjected to an intermediate annealing treatment at 480 ° C. for 14 hours , A 0.08 mm thick clad sheet material was produced through the same process.

Table 3 below summarizes the compositions of the clad core materials according to Examples 1 to 9 and Comparative Examples 1 and 2 of the present invention.

Clad
Core material Composition (% by weight) Si Fe Mn Zn Ti Zr Cr Cu Example 1 0.40 0.52 1.43 0.81 0.027 - - - Example 2 0.38 0.52 1.25 1.13 0.096 - - - Example 3 0.38 0.54 1.25 1.17 0.17 - - - Example 4 0.38 0.54 1.24 1.41 0.028 0.88 - - Example 5 0.38 0.51 1.24 1.15 0.030 - 0.11 - Example 6 0.40 0.54 1.26 0.81 0.027 - 0.19 - Example 7 0.37 0.52 1.22 1.41 0.088 - - 0.25 Example 8 0.37 0.53 1.24 1.34 0.032 0.091 - 0.25 Example 9 0.38 0.50 1.25 0.84 0.029 - 0.11 0.25 Comparative Example 1 0.39 0.56 1.43 0.84 0.027 - - 0.29 Comparative Example 2 0.38 0.53 1.25 0.82 0.027 0.18 - -

The tensile strength before and after the brazing, which can evaluate the possibility of reducing the weight of the clad plate produced according to Examples 1 to 9 and Comparative Examples 1 and 2 manufactured as described above, and the bending workability Evaluation of sag resistance in the brazing process, and evaluation of sacrificial agitation associated with the life of the heat exchanger.

Tensile Strength Evaluation

Table 4 below shows the tensile strength of the clad material after the cladding process by roll bonding and the heat treatment of the final processed plate at a thickness of 0.08 mm under the condition of holding at 610 캜 for 10 minutes which is similar to the brazing process condition, And the results of measuring the strength are shown.

Clad material Clad material Brazing Heat-treated clad material The tensile strength
(MPa) Yield strength
(MPa) Elongation
(%) The tensile strength
(MPa) Yield strength
(MPa) Elongation
(%) Example 1 201 194 0.61 163 67 8.16 Example 2 199 195 0.71 165 66 7.68 Example 3 200 195 0.66 171 68 7.88 Example 4 210 205 0.73 170 69 7.91 Example 5 202 195 0.71 164 66 6.24 Example 6 205 201 0.66 165 70 6.96 Example 7 228 218 1.01 164 62 7.14 Example 8 230 225 0.70 167 62 8.54 Example 9 226 217 0.83 176 65 9.44 Comparative Example 1 234 222 1.04 173 69 8.13 Comparative Example 2 215 209 0.76 163 67 6.87

As shown in Table 4, most of the clad materials after roll bonding had a tensile strength of 200 MPa or more, and in particular, the tensile strengths of Examples 7 to 9 and Comparative Example 1 were relatively high.

However, the tensile strength after application of the brazing process did not differ greatly between Examples and Comparative Examples, and Examples 1 to 9 and Comparative Examples 1 and 2 exhibited relatively high strength of 160 MPa or more.

Formability evaluation

The minimum radius of curvature at which no peeling of the substrate or cutting of the plate material occurred during the corrugation processing of the clad material processed with the fin material was evaluated by a W-bending test.

Specifically, according to JIS H3110 standard, the W-bending test was performed by changing the tip radius of the W-shaped 90 ° bending block from 0.05 to 1.0 mm, and the bending test was carried out. At this time, The minimum tip radius at which no defects such as cutting occurred was taken as the minimum bending ratio, and the value divided by the thickness of the specimen was expressed as MBR / t. Table 5 below shows the results of the W-bending test.

Clad material Minimum Curvature Radius (MBR)
(mm) MBR / t Example 1 &Lt; 0.05 <0.6 Example 2 &Lt; 0.05 <0.6 Example 3 &Lt; 0.05 <0.6 Example 4 &Lt; 0.05 <0.6 Example 5 &Lt; 0.05 <0.6 Example 6 &Lt; 0.05 <0.6 Example 7 &Lt; 0.05 <0.6 Example 8 &Lt; 0.05 <0.6 Example 9 &Lt; 0.05 <0.6 Comparative Example 1 &Lt; 0.05 <0.6 Comparative Example 2 &Lt; 0.05 <0.6

As shown in Table 5, the minimum radius of curvature in which all the cladding was not peeled off or the shear of the plate was not generated was 0.05 mm or less, which was a level at which no problem was encountered in the corrugation molding process.

Sag Resistance Evaluation

2 schematically shows a method for evaluating sag resistance. As shown in FIG. 2, after fixing one side of the plate material processed to the jig and holding the other side at a free end, the same heat treatment as the brazing process conditions is performed, and then the distance L ₀ ) and the sag distance after heat treatment (L ₁ ).

On the other hand, the measured value of the sag distance is influenced by the state of the test piece fixed to the jig. In the embodiment of the present invention, the test piece having a length of 50 mm from the tip of the jig to the free end of the test piece is used.

The heat treatment conditions were maintained at 610 ° C for 10 minutes, which was similar to the brazing process conditions, and the average and standard deviation were obtained after three tests were performed for each specimen. Table 6 below shows the sag distance measurement results.

Clad material Average
(mm) Standard Deviation Example 1 30.3 2.5 Example 2 24.3 2.9 Example 3 24.3 3.2 Example 4 26.3 4.9 Example 5 19.0 2.0 Example 6 25.7 2.5 Example 7 22.0 1.7 Example 8 23.0 1.0 Example 9 19.7 1.5 Comparative Example 1 19.0 2.6 Comparative Example 2 32.3 3.1

As shown in Table 6, Examples 1 to 9 and Comparative Example 1 of the present invention generally satisfy the sag distance of 30 mm or less required in the brazing process (in the case of Example 1, In comparison example 2, sagging is performed by 2 mm or more than 30 mm in the case of the comparative example 2, so that it is not suitable for the brazing fin material.

Assessment of victimization gender

Through the corrosion potential of the core material, the clad material was evaluated for sacrificial resistance to the tube material. The corrosion potential was measured by immersing the specimen in a 1M sodium chloride solution and measuring the open circuit potential using Ag / AgCl standard electrode. The corrosion potential was measured for 600 to 1800 seconds and the converged potential was obtained. And -45 mV was added to convert to a commonly used SCE value. Table 7 below shows the evaluation results.

Clad material Average
(mV) Standard Deviation Example 1 -799.4 12.8 Example 2 -814.5 4.8 Example 3 -796.7 3.5 Example 4 -859.6 5.6 Example 5 -805.3 8.3 Example 6 -813.9 7.7 Example 7 -796.6 4.9 Example 8 -788.0 10.8 Example 9 -768.9 8.1 Comparative Example 1 -736.9 7.1 Comparative Example 2 -825.2 4.1

As shown in Table 7, the core materials of the clad materials according to Examples 1 to 9 of the present invention show SCE corrosion potentials lower than -770 mV, but in the case of Comparative Example 1, since the corrosion potential is as high as -736 V, The sacrificial mode characteristics for the tube may not be sufficient when bonded to the tube relative to the core contained in the tube.

In particular, Example 4 of the present invention shows that it can exhibit a very excellent sacrificial mode characteristic as compared with other examples and the comparative example.

Claims (17)

(Si), 0.35-0.55% iron (Fe), 1.15-1.50% manganese (Mn), 0.70-1.50% zinc (Zn), and 0.02-0.25 wt% A core made of an aluminum alloy containing titanium (Ti), the remaining aluminum (Al) and an unavoidable impurity,
And an object made of an aluminum alloy clad on one or both surfaces of the core material and containing silicon (Si). The method according to claim 1,
Wherein the core material further comprises at least one selected from 0.07 to 0.25 weight% of chromium (Cr) and 0.07 to 0.15 weight% of zirconium (Zr). 3. The method of claim 2,
Wherein the chromium (Cr) is 0.07 to 0.13 wt%. The method according to claim 1,
Wherein the core further comprises 0.20 to 0.35% by weight of copper (Cu), and the content of titanium is 0.07 to 0.13%. 5. The method according to any one of claims 1 to 4,
Wherein the workpiece comprises 6.8 to 8.2% by weight of silicon (Si). 5. The method according to any one of claims 1 to 4,
Wherein the clad material has a tensile strength after brazing of 160 MPa or more. 5. The method according to any one of claims 1 to 4,
Wherein the sag distance of the clad material is 30 mm or less. 5. The method according to any one of claims 1 to 4,
Wherein the corrosion potential of the core material constituting the clad material is lower than -770 mV. A heat exchanger comprising a fin material formed of the clad material according to any one of claims 1 to 4 and a tube brazed to the fin material. (Si), 0.35-0.55% iron (Fe), 1.15-1.50% manganese (Mn), 0.70-1.50% zinc (Zn), and 0.02-0.25 wt% 1. A method for manufacturing an aluminum alloy, comprising the steps of: preparing a base material obtained by thin-casting an aluminum alloy containing titanium (Ti), the remaining aluminum (Al) and an unavoidable impurity, and an aluminum alloy containing silicon (Si)
Subjecting the core material and the substrate to a homogenization treatment and cold-rolling the homogenized substrate,
A step of surface-treating the joining surface of the core material and the substrate,
And laminating and laminating the objects so that the joint surfaces are in contact with each other on one or both surfaces of the core material. 11. The method of claim 10,
Wherein the core further comprises at least one selected from 0.07 to 0.25 weight% of chromium (Cr) and 0.07 to 0.25 weight% of zirconium (Zr). 12. The method of claim 11,
Wherein the chromium (Cr) is 0.07 to 0.13% by weight. 11. The method of claim 10,
Wherein the core further comprises 0.20 to 0.35% by weight of copper (Cu), and the content of titanium is 0.07 to 0.13%. 11. The method of claim 10,
Wherein the workpiece comprises 6.8 to 8.2% by weight of silicon (Si). 11. The method of claim 10,
Wherein the core material and the substrate are homogenized at a temperature of 400 to 500 占 폚 for 1 to 24 hours. 11. The method of claim 10,
Wherein the surface treatment of the bonding surface is a wire brushing. 11. The method of claim 10,
Further comprising annealing the clad material obtained by bonding the core material and the substrate at a temperature of 400 to 500 ° C for 8 to 24 hours,
And after the annealing, cold rolling at a final reduction ratio of 30 to 50%.

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