JP4860203B2 - Laminated material for heat exchanger, tube material for heat exchanger, header material for heat exchanger, manufacturing method of heat exchanger, and heat exchanger - Google Patents

Description

  The present invention is used, for example, as a constituent material of various other heat exchangers for automobiles manufactured by brazing, and is particularly suitable for a member requiring high strength and high corrosion resistance, and a laminated material for a heat exchanger, and this The present invention relates to a tube material for a heat exchanger made of a laminated material, a header material for a heat exchanger, a manufacturing method of the heat exchanger, and a heat exchanger.

In a component for a next generation CO ₂ heat exchanger using CO ₂ as a refrigerant, for example, a tube or a header, an Al—Mn alloy (3003) alloy is used in order to require high strength at a high temperature. It was customary. In addition, a technique of adding Cu to an Al—Mn alloy in order to obtain further high temperature and high strength is also disclosed (Patent Documents 1, 2, and 3).

  Patent Document 4 discloses that an Al—Si—Fe—Cu—Mn alloy core material containing Cu: 0.1 to 1.0 wt% is formed on one surface with an Al—Sl alloy brazing material and the other surface is formed with Ca. An aluminum alloy composite for vacuum brazing, which is clad with an Al—Zn-based alloy material containing Nb, is disclosed.

Patent Document 5 discloses an Al—Si brazing material containing Cu: more than 0.4 wt% and not more than 8.0 wt% Cu on one surface of an Al—Si—Fe—Cu—Mn alloy core material. A clad aluminum alloy brazing sheet is disclosed.
Japanese Patent No. 2528187 JP 2000-119784 A JP 2003-27166 A JP-A-8-260085 JP-A-9-194975

  However, when Cu is added to the Al—Mn alloy, high strength can be obtained, but since deformation resistance at high temperatures is high, it is possible to manufacture a fine heat exchanger component with poor workability. In addition, when Cu is contained in the tube core material, there is a problem that the corrosion resistance is remarkably deteriorated depending on the combination with adjacent materials such as a fin material.

  In addition, the aluminum alloy composite material described in Patent Document 4 and the aluminum brazing sheet described in Patent Document 5 have a high Cu content in the core material and the skin material clad on the core material. There was a problem of deterioration.

  The present invention has been made in view of such circumstances, and provides a heat exchanger material excellent in both high-temperature strength and corrosion resistance, for example, a material used for a tube or a header. It aims at providing a manufacturing method and a heat exchanger.

  In order to achieve the above object, in the present invention, the core material is an Al-Si-Cu-Mn-Ti-Zr alloy, or further, a layer having a high Si concentration is formed on the surface layer of the core material, Zn and Cu are added to the skin material. By forming the Si concentrated layer, a Si-rich Cu, Mn, Ti, Zr alloy is formed on the surface of the core material, and the high-temperature strength is further improved as compared with the case of the core material alone. Further, Zn contained in the skin material diffuses into the surface layer of the tube core material to form a sacrificial anticorrosive layer. As for Cu and Zn contained in the skin material, since the diffusion distance of Zn is larger than the diffusion distance of Cu (Zn is more easily diffused), surface corrosion proceeds in the sacrificial corrosion layer of Zn. However, the corrosion toward the core material due to the addition of Cu to the skin does not proceed, and the corrosion proceeds only inside the sacrificial corrosion layer (a layer that is preferentially corroded to protect other parts). There is no.

That is, the present invention provides the following solutions.
(1) Si; 1.25% by mass to 2.45% by mass, Fe; 0.15% by mass to 0.8% by mass, Cu; 0.01% by mass to 0.08% by mass, Mn; 1.4 mass% or more and 2.05 mass% or less, Ti; 0.05 mass% or more and 0.2 mass% or less, Zr; 0.12 mass% or more and 0.3 mass% or less, with the balance being Al and impurities The core material is made of an aluminum material, and Si: 7.5% by mass or more and 11.5% by mass or less, Fe: 0.2% by mass or more and 0.8% by mass or less, Cu; 0.005% by mass or more and 0.35% by mass or less, Zn; 0.005% by mass or more and 0.4% by mass or less, and a laminated material for a heat exchanger in which an aluminum skin made of Al and impurities is laminated.
(2) Si; 1.25 mass% to 2.45 mass%, Fe; 0.15 mass% to 0.8 mass%, Cu; 0.01 mass% to 0.08 mass%, Mn; 1.4 mass% or more and 2.05 mass% or less, Ti; 0.05 mass% or more and 0.2 mass% or less, Zr; 0.12 mass% or more and 0.3 mass% or less, with the balance being Al and impurities The core material is made of an aluminum material, and Si: 7.5% by mass or more and 11.5% by mass or less, Fe: 0.2% by mass or more and 0.8% by mass or less, Cu; 0.005 mass% or more and 0.35 mass% or less, Zn; 1 mass% or more and 5 mass% or less, The laminated material for heat exchangers by which the aluminum skin material which consists of Al and an impurity is laminated | stacked.
(3) In the said core material, Si; 1.35 mass% or more and 1.65 mass% or less, Fe; 0.3 mass% or more and 0.5 mass% or less, Cu; 0.02 mass% or more and 0.04 mass% % Or less, Mn: 1.55 mass% or more and 1.75 mass% or less, Ti: 0.08 mass% or more and 0.15 mass% or less, Zr: 0.12 mass% or more and 0.2 mass% or less, In the skin material, Si: 7.5% by mass to 9.5% by mass, Fe: 0.2% by mass to 0.5% by mass, Cu: 0.005% by mass to 0.3% by mass, Zn: The laminated material for heat exchangers according to 1 above, which is 0.005 mass% or more and 0.3 mass% or less.
(4) In the said core material, Si; 1.35 mass% or more and 1.65 mass% or less, Fe; 0.3 mass% or more and 0.5 mass% or less, Cu; 0.02 mass% or more and 0.04 mass% % Or less, Mn: 1.55 mass% or more and 1.75 mass% or less, Ti: 0.08 mass% or more and 0.15 mass% or less, Zr: 0.12 mass% or more and 0.2 mass% or less, In the skin material, Si: 7.5% by mass to 9.5% by mass, Fe: 0.2% by mass to 0.5% by mass, Cu: 0.005% by mass to 0.3% by mass, Zn: The laminated material for heat exchangers of the preceding clause 2 which is 1 mass% or more and 2.5 mass% or less.
(5) The heat exchange according to any one of the preceding items 1 to 4, wherein the Mg content as an impurity of the core material is 0.04 mass% or less and the Zn content as an impurity is limited to 0.08 mass% or less. Laminated material.
(6) The laminated material for a heat exchanger according to any one of 1 to 5 above, wherein Cr is contained in the core material in an amount of 0.03% by mass or more and 0.25% by mass or less.
(7) The laminated material for a heat exchanger according to any one of items 1 to 6, wherein Ni is contained in the core material in an amount of 0.05% by mass to 1% by mass.
(8) The laminated material for a heat exchanger according to any one of items 1 to 7, wherein Sc is contained in the core material in an amount of 0.005% by mass to 0.1% by mass.
(9) As an intermediate layer between the core material and the skin material, Si: 0.05% by mass or more and 2.45% by mass or less, Fe: 0.05% by mass or more and 1.8% by mass or less, Cu; 01% by mass to 0.3% by mass, Mn: 0.05% by mass to 2% by mass, Ti: 0.01% by mass to 0.2% by mass, Zn: 0.5% by mass to 2.5% 9% by mass or less, Zr; 0.005% by mass or more and 0.3% by mass or less, wherein the balance is laminated with an aluminum material made of Al and impurities. Laminated material.
(10) Any of 1 to 9 above, wherein the surface layer of the core material has a Si concentrated layer having a thickness of 50 μm or more and 500 μm or less, and the average Si concentration of the concentrated layer is 1.4% by mass or more and 5% by mass or less. A laminate for a heat exchanger according to claim 1.
(11) Si; 0.9 mass% or more and less than 1.25 mass%, Fe; 0.15 mass% or more and 0.8 mass% or less, Cu; 0.01 mass% or more and 0.2 mass% or less, Mn; 1.4% by mass or more and 2.05% by mass or less, Ti; 0.05% by mass or more and 0.2% by mass or less, Zr; 0.12% by mass or more and 0.3% by mass or less, and Mg as an impurity; 0.04% by mass or less, Zn: 0.08% by mass or less, and an aluminum material composed of Al and impurities as a core is used as a core material, and Si: 7.5% by mass on at least one side of the core material 11.5% by mass or less, Fe: 0.2% by mass or more and 0.8% by mass or less, Cu: 0.005% by mass or more and 0.35% by mass or less, Zn: 0.005% by mass or more and 0.4% by mass % Of aluminum and the balance is made of aluminum and inevitable impurities. For heat exchangers in which the material is laminated, the core layer has a Si concentrated layer of 50 μm or more and 500 μm or less, and the average Si concentration of the concentrated layer is 1.4 mass% or more and 5 mass% or less Laminated material.
(12) Si; 0.9 mass% or more and less than 1.25 mass%, Fe; 0.15 mass% or more and 0.8 mass% or less, Cu; 0.01 mass% or more and 0.2 mass% or less, Mn; 1.4% by mass or more and 2.05% by mass or less, Ti; 0.05% by mass or more and 0.2% by mass or less, Zr; 0.12% by mass or more and 0.3% by mass or less, and Mg as an impurity; 0.04% by mass or less, Zn: 0.08% by mass or less, and an aluminum material composed of Al and impurities as a core is used as a core material, and Si: 7.5% by mass on at least one side of the core material 11.5% by mass or less, Fe: 0.2% by mass or more and 0.8% by mass or less, Cu: 0.005% by mass or more and 0.35% by mass or less, Zn: 1% by mass or more and 5% by mass or less For heat exchangers, the balance of which is laminated with aluminum skin made of Al and impurities Layer material.
(13) The laminated material for a heat exchanger as described in (11) or (12) above, wherein Cr is contained in the core material by 0.03% by mass or more and 0.25% by mass or less.
(14) The laminated material for a heat exchanger according to any one of the above items 11 to 13, wherein Ni is contained in the core material in an amount of 0.05% by mass or more and 1% by mass or less.
(15) The heat exchanger laminate according to any one of the above items 11 to 14, wherein Sc is contained in the core material in an amount of 0.005 mass% to 0.1 mass%.
(16) As an intermediate layer between the core material and the skin material, Si: 0.05% by mass or more and 2.45% by mass or less, Fe: 0.05% by mass or more and 1.8% by mass or less, Cu; 01% by mass to 0.3% by mass, Mn: 0.05% by mass to 2% by mass, Ti: 0.01% by mass to 0.2% by mass, Zn: 0.5% by mass to 2.5% 16% by mass or less, Zr; 0.005% by mass or more and 0.3% by mass or less, and the heat exchanger according to any one of 11 to 15 above, wherein the balance is formed by laminating an aluminum material made of Al and impurities. Laminated material.
(17) The preceding item, wherein the core material and the skin material, or the core material, the intermediate layer and the skin material are subjected to a heat treatment at least once, at least 400 ° C. to 550 ° C., for 20 minutes to 10 hours. The laminated material for heat exchangers as described in any one of 1-16.
(18) The laminated material for a heat exchanger as described in 17 above, wherein the heat treatment is performed at 400 ° C. or more and 500 ° C. or less and 30 minutes or more and 8 hours or less.
(19) The heat exchanger tube, characterized by comprising the laminated material according to any one of (1) to (4) or (11) or (12) above, wherein a skin material in the laminated material is formed by a thermal spraying method. Wood.
(20) A heat exchanger tube material comprising the laminated material according to the preceding item 9 or the preceding item 16, wherein an intermediate material in the laminated material is formed by a thermal spraying method.
(21) The Si-enriched layer in the laminated material is coated with an Al—Si based alloy on the outer peripheral portion of the tube body by a thermal spraying method, and then heated. A heat exchanger tube material characterized by being formed by diffusion.
(22) A tube material for a heat exchanger, comprising the laminated material according to (17) or (18), wherein a pre-strain of 0.2% to 50% is given as the equivalent strain after the heat treatment.
(23) A header for a heat exchanger, comprising the laminated material according to any one of items 1 to 4 or 11 or 12 above, wherein the skin material in the laminated material is formed by a thermal spraying method. Wood.
(24) A header material for a heat exchanger, comprising the laminate material according to item 9 or 16, wherein an intermediate material in the laminate material is formed by a thermal spraying method.
(25) Consisting of the laminated material according to 10 or 11 above, the Si concentrated layer in the laminated material coats the outer peripheral portion of the header body with an Al-Si alloy by thermal spraying, and then heat A header material for a heat exchanger, characterized by being formed by diffusion.
(26) A header material for a heat exchanger, comprising the laminated material according to item (17) or item (18), wherein a pre-strain of 0.2% to 50% is applied as the equivalent strain after the heat treatment.
(27) Using the heat exchanger laminate according to any one of the preceding items 1 to 9 as a heat exchanger constituent member, and brazing the constituent member with a fluoride-based flux, the surface layer of the core material A method for producing a heat exchanger in which a Si concentrated layer having a thickness of 50 μm or more and 500 μm or less is formed, and an average Si concentration of the concentrated layer is 1.4% by mass or more and 5% by mass or less.
(28) A heat exchanger produced by using the tube material according to any one of items 19 to 22.
(29) A heat exchanger produced by using the header material according to any one of items 23 to 26.

  According to the invention described in the preceding item (1), a laminated material for a heat exchanger excellent in high-temperature strength and corrosion resistance can be formed by a combination of alloy compositions of a core material and a skin material.

  According to the invention described in item (2) above, a laminated material for a heat exchanger excellent in high-temperature strength and corrosion resistance can be formed by a combination of alloy compositions of a core material and a skin material.

  According to the invention described in the preceding item (3), a laminate for a heat exchanger that is further excellent in high-temperature strength and corrosion resistance can be obtained.

  According to the invention described in item (4) above, a laminate for a heat exchanger that is further excellent in high-temperature strength and corrosion resistance can be obtained.

  According to the invention described in the preceding item (5), it can be formed as a heat exchanger laminate having good brazing properties and improved self-corrosion resistance of the core material.

  According to the invention described in the preceding item (6), the core material contains a predetermined range of Cr, so that it can be made a laminated material for a heat exchanger further excellent in high temperature strength.

  According to the invention described in item (7), when the core material contains Ni in a predetermined range, a laminated material for a heat exchanger that is further excellent in high-temperature strength can be obtained.

  According to the invention described in the preceding item (8), the core material contains Sc in a predetermined range, so that it can be a laminated material for a heat exchanger that is further excellent in high-temperature strength.

  According to the invention described in the preceding item (9), the presence of the intermediate layer can provide a laminate for a heat exchanger that is further excellent in corrosion resistance.

  According to the invention described in item (10) above, the presence of the Si concentrated layer can provide a laminated material for a heat exchanger that is further excellent in high-temperature strength.

  According to the invention described in the above item (11), the combination of the alloy composition of the core material and the skin material and the presence of the Si concentrated layer can be used as a heat exchanger laminate material excellent in high temperature strength and corrosion resistance.

  According to the invention described in item (12) above, a laminated material for a heat exchanger excellent in high-temperature strength and corrosion resistance can be obtained by a combination of alloy compositions of a core material and a skin material.

  According to the invention of the preceding item (13), when the core material contains Cr in a predetermined range, a laminated material for a heat exchanger that is further excellent in high-temperature strength can be obtained.

  According to the invention described in the preceding item (14), the core material contains Ni in a predetermined range, so that it can be a laminated material for a heat exchanger further excellent in high temperature strength.

  According to the invention described in the preceding item (15), when the core material contains Sc in a predetermined range, a laminated material for a heat exchanger that is further excellent in high-temperature strength can be obtained.

  According to the invention described in the above item (16), the presence of the intermediate layer can provide a laminated material for a heat exchanger that is further excellent in corrosion resistance.

  According to the invention described in the preceding item (17), the heat exchanger can be made into a heat exchanger laminated material that is further excellent in high-temperature strength by heat treatment.

  According to the invention described in the preceding item (18), by performing a suitable heat treatment, a laminate for a heat exchanger that is further excellent in high-temperature strength can be obtained.

  According to the invention described in the preceding item (19), it can be a tube material for a heat exchanger excellent in high temperature strength and corrosion resistance.

  According to the invention described in the preceding item (20), the heat exchanger tube material can be further improved in corrosion resistance.

  According to the invention described in the preceding item (21), the heat exchanger tube material can be further excellent in high-temperature strength.

  According to the invention described in the preceding item (22), the tube material for a heat exchanger can be formed with further improved high-temperature strength after brazing.

  According to the invention described in the preceding item (23), a header material for a heat exchanger excellent in high-temperature strength and corrosion resistance can be obtained.

  According to the invention described in the preceding item (24), a header material for a heat exchanger having further excellent corrosion resistance can be obtained.

  According to the invention described in the preceding item (25), it can be a header material for a heat exchanger that is further excellent in high-temperature strength.

  According to the invention described in the preceding item (26), a header material for a heat exchanger that further improves high-temperature strength after brazing can be obtained.

  According to the invention described in item (27), a heat exchanger excellent in high-temperature strength and corrosion resistance can be manufactured.

  According to the invention described in item (28) above, a heat exchanger excellent in high-temperature strength and corrosion resistance can be obtained.

  According to the invention described in the preceding item (29), a heat exchanger excellent in high-temperature strength and corrosion resistance can be obtained.

  Next, the configuration of the present invention and the reason thereof will be described.

Since the tube material and the header material used in the heat exchanger using CO ₂ as a refrigerant partially have a portion used in a high temperature and high pressure environment at 120 to 200 ° C., the constituent material has a high temperature. Strength is required. In the present invention, in view of being used for this purpose, the combination of Si, Fe, Cu, Mn, and Zr contained in the core material that bears most of the material strength is optimized in order to improve the strength at high temperatures. In addition, as a more desirable form, a layer having a higher Si concentration than the core material is formed thinly as a concentrated layer on the outer layer of the core material. Furthermore, in order to suppress pitting corrosion and intergranular corrosion in a corrosive environment, the present invention has been completed by adopting a laminated material structure in which Ti is added to the core material and Zn and Cu are added to the skin material.

  For this purpose, the Si content of the core material needs to be 0.9 mass% or more and 2.45 mass% or less. When the Si content is less than 0.9% by mass, there is no effect of securing high-temperature strength. And corrosion resistance can be ensured together. If it exceeds 2.45% by mass, the hot deformability is remarkably reduced and hot cracking is caused. Therefore, the molding processability as a wrought material is insufficient such as hot rolling, hot extrusion, hot forging, etc. It becomes. Also, due to the formation of an Al-Si-based eutectic, the melting point is lowered, the core material is melted during brazing, and pores of 1 μm or more, and in some cases several millimeters are formed inside. Cause. Desirable Si content is 1.35 mass% or more and 1.65 mass% or less.

  The Fe content of the core material needs to be 0.15% by mass or more and 0.8% by mass or less. When the Fe content is less than 0.15% by mass, there is no effect of securing high-temperature strength, and when it exceeds 0.8% by mass, a coarse Al—Fe—Si intermetallic compound is formed, which adversely affects corrosion resistance. . Desirable Fe content is 0.3 mass% or more and 0.5 mass% or less.

  The Cu content of the core material needs to be 0.01% by mass or more and 0.2% by mass or less. Cu is an element that improves the high-temperature strength of the material, but if the Cu content is less than 0.01% by mass, there is no effect of securing high-temperature strength, and if it exceeds 0.2% by mass, the corrosion resistance is adversely affected. . When the Si content is in the range of 1.25% by mass to 2.45% by mass, the Cu content is preferably 0.08% by mass or less from the viewpoint of corrosion resistance. When the Si content is in the range of 0.9% by mass or more and less than 1.25% by mass, the effect of improving the strength by Si is not sufficient. Also good. Desirable Cu content is 0.02 mass% or more and 0.04 mass% or less.

  The Mn content of the core material needs to be 1.4 mass% or more and 2.05 mass% or less. Mn is an element that improves the high temperature strength by improving the recrystallization temperature. However, if the Mn content is less than 1.4% by mass, there is no effect of securing the high temperature strength, and if it exceeds 2.05% by mass. , Al— (Fe, Mn) —Si based intermetallic compounds are formed, which adversely affects the corrosion resistance. Desirable Mn content is 1.55 mass% or more and 2 mass% or less, More desirably, it is 1.75 mass% or less.

  The Zr content of the core material needs to be 0.12% by mass or more and 0.3% by mass or less. Zr is an element that improves the high temperature strength by improving the recrystallization temperature. However, if the amount of Zr is less than 0.12% by mass, there is no effect of securing high temperature strength, and if it exceeds 0.3% by mass, It becomes difficult to dissolve at the time of dissolution. Desirable Zr content is 0.12 mass% or more and 0.2 mass% or less.

  In particular, the Zr improves its performance as compared with the addition of a single substance by coexistence with Si and Mn. For this reason, the amount of Zr added is particularly important for state control in the aluminum alloy matrix. For this reason, it is desirable that the laminated material is subjected to heat treatment at 400 ° C. or higher and 550 ° C. or lower for 20 minutes or longer and 10 hours or shorter at least once. Further desirable ranges are 400 ° C. or more and 500 ° C. or less, and 30 minutes or more and 8 hours or less. Of course, the high temperature strength level described in the present invention can be obtained even without this heat treatment. However, heat treatment at 200 ° C. or more and less than 400 ° C. should be avoided from the viewpoint of maintaining high temperature strength.

  The Ti content of the core material needs to be 0.05% by mass or more and 0.2% by mass or less. Ti is added to suppress the progress of intergranular corrosion. If the Ti content is less than 0.05% by mass, the effect is not obtained. If the Ti content exceeds 0.2% by mass, problems such as casting cracks tend to occur. Desirable Ti content is 0.08 mass% or more and 0.15 mass% or less.

  The core material is allowed to contain an impurity element. In particular, the amount of Mg as an impurity is 0.04% by mass or less from the viewpoint of improving brazeability, and the amount of Zn is a manifestation of the sacrificial anticorrosive effect of Zn in the skin material. For the purpose of improving the self-corrosion resistance of the core material, it is desirable to regulate it to 0.08% by mass or less.

  Moreover, Cr: 0.03 mass% or more and 0.25 mass% or less, Ni: 0.05 mass% or more and 1 mass% or less, Sc: 0.005 mass% or more and 0.1 as needed for a core material You may contain at least any of the mass% or less.

  The Cr is added to improve the high temperature strength of the core material. If the Cr content is less than 0.03% by mass, the effect is not obtained. If the Cr content exceeds 0.25% by mass, the deformation resistance at high temperature becomes too high, and the moldability is lowered.

  Ni is added to improve the high-temperature strength of the core material. If the Ni content is less than 0.05% by mass, the effect is not achieved, and if it exceeds 1% by mass, the corrosion resistance is adversely affected.

  The Sc is added to improve the high temperature strength of the core material. If the Sc content is less than 0.005% by mass, the effect is not obtained, and if it exceeds 0.1% by mass, the cost increases.

  It should be noted that V: 0.01 to 0.4 mass for the purpose of further improving the high-temperature strength of the core material together with one or more of Cr, Ni, and Sc or without containing Cr, Ni, and Sc. % May be contained.

  Moreover, Y: 0.01 to 0.3% by mass for the purpose of further improving the high-temperature strength of the core material together with one or more of Cr, Ni, and Sc or without containing Cr, Ni, and Sc. , La: 0.01 to 0.3 mass%, Ce: 0.01 to 0.2 mass% may be contained.

  Next, a material coated on the surface of the core material as a skin material will be described.

  The Si content of the skin material needs to be 7.5% by mass or more and 11.5% by mass or less. When the Si content is less than 7.5% by mass, the brazing flowability is lowered, a stable fillet is not formed, and the brazing performance is significantly lowered. On the other hand, if it exceeds 11.5% by mass, primary Si is likely to be formed in the fillet, and the corrosion resistance of the fillet is significantly reduced. Desirable Si content is 7.5 mass% or more and 9.5 mass% or less.

  The Fe content of the skin material needs to be 0.2% by mass or more and 0.8% by mass or less. When the Fe content is less than 0.2% by mass, the brazing flowability is lowered. Moreover, when it exceeds 0.8 mass%, the corrosion resistance of a fillet will fall. Desirable Fe content is 0.2 mass% or more and 0.5 mass% or less.

  The Cu content of the skin material needs to be 0.005 mass% or more and 0.35 mass% or less. When the Cu content is less than 0.005% by mass, the potential of the brazing material (skin material) becomes too low with respect to the core material, and as a result, the corrosion resistance of the fillet during brazing is lowered. Further, if it exceeds 0.35% by mass, the potential of the brazing material becomes too noble with respect to the core material, and as a result, preferential corrosion occurs at the interface between the fillet and the core material at the time of brazing, and the corrosion resistance is significantly reduced. . Desirable Cu content is 0.005 mass% or more and 0.3 mass% or less.

  Zn of the skin material is an element that should be properly used depending on whether the brazing material layer and the Zn concentrated layer formed after brazing have a sacrificial corrosion layer and have an anticorrosive function effect. In other words, the sacrificial anticorrosive effect due to the addition of Zn should be positively utilized in the part that is actively exposed to the corrosive environment. In such a case, the Zn content needs to be 1% by mass or more and 5% by mass or less. When the Zn content is less than 1% by mass, there is no sacrificial anticorrosive effect due to the Zn concentrated layer, and pitting corrosion is likely to occur, and the life when used as a tube material or a fin material is reduced. If it exceeds 5% by mass, the corrosion resistance of the entire laminated material including the brazing material and by extension the core material will be significantly reduced. Desirable Zn content is 1 mass% or more and 2.5 mass% or less.

  On the other hand, on the tube and header inner surface that do not require sacrificial corrosion protection, it is effective to set Zn content to 0.005% by mass or more and 0.4% by mass or less to suppress unnecessary reduction in self-corrosion resistance due to the addition of Zn. . Desirable Zn content in this case is 0.005 mass% or more and 0.3 mass% or less.

  In the present invention, of course, even if it is the inner surface of the tube or header, if sacrificial anticorrosive effect is required due to the nature of the working fluid, Zn should be added as necessary, and the necessity of anticorrosion even on the outer surface Is low or not at all, it does not limit the structure in which Zn is not added.

  As shown in FIG. 1, the laminate 1 of the present invention may have a configuration in which the skin material 3 is laminated only on one surface of the core material 2, or on both surfaces of the core material 2 as shown in FIG. 2. The structure by which the skin materials 3 and 4 were laminated | stacked may be sufficient. When the skin materials 3 and 4 are laminated | stacked on both surfaces of the core material 2, the skin material 3 and the skin material 4 are good also as a thing of the same composition, and it is good also as a skin material from which Zn amount etc. differ as mentioned above.

  Furthermore, as a method of imparting corrosion resistance, an intermediate layer 5 may be provided between the core material 2 and the skin material 3 or 4 as shown in FIG. In this case, the composition of the intermediate layer 5 is Si: 0.05% by mass or more and 2.45% by mass or less, Fe: 0.05% by mass or more and 1.8% by mass or less, Cu: 0.01% by mass or more and 0.3% by mass or more. % By mass or less, Mn: 0.05% by mass or more and 2% by mass or less, Ti: 0.01% by mass or more and 0.2% by mass or less, Zn: 0.5% by mass or more and 2.5% by mass or less, Zr: 0 Although the effect is also recognized by setting it to 0.005 mass% or more and 0.3 mass% or less, the Zn content of the core material is 0.08 mass% or less, and the Si, Fe, Mn, and Ti contents of the intermediate layer are It is assumed to be equal to or less than the core material composition, and Cu content is 0.01 mass% or more and 0.3 mass% or less, and Zn content is 0.5 mass% or more and 2.5 mass% or less. This makes it possible to stop the progress of corrosion in the intermediate layer. By adopting such a configuration, since corrosion does not progress to the core material, it is possible to suppress a decrease in material strength, particularly high-temperature strength and high-temperature fatigue strength, due to thinning due to corrosion of the core material. Of course, the intermediate layer can contain other trace elements such as Mg, Cr, and Ni as long as the sacrificial anticorrosive function is not impaired.

  Next, the effect of the Si concentrated layer will be described. As described above, the core material 2 contains Si in a range of 0.9 mass% to 2.45 mass%. This Si amount is effective in improving the strength up to 5% by mass, except for the moldability as a wrought material. Therefore, as shown in FIG. 4, the effect of coexistence with Zr and Mn can be further enhanced by forming the Si concentrated layer 6 on the surface layer of the core material 2. The Si-enriched layer 6 contributing to the improvement of the high-temperature strength has a layer thickness of less than 50 μm, and the layer thickness is too thin to reveal its effect. When the layer thickness exceeds 500 μm, the corrosion resistance of the surface layer is not observed. The strength in the actual environment is reduced by the reduction of corrosion. Further, if the average Si concentration of the concentrated layer is less than 1.4% by mass, the effect of increasing the high-temperature strength is not recognized as compared with the core material, and if it exceeds 5% by mass, the corrosion resistance is adversely affected.

  In addition, the Si concentrated layer should just be formed in the site | part where intensity | strength is requested | required at least.

  The heat treatment of the laminated material 1 is important from the viewpoints of both the formation of the Si concentrated layer and the heat treatment effect on the core material. For this reason, heat treatment of 400 ° C. or more and 550 ° C. or less and 20 minutes or more and 10 hours or less for the purpose of improving the high-temperature strength of the above-described core material, more preferably 400 ° C. or more and 500 ° C. or less, 30 minutes or more and 8 hours or less The Si concentrated layer 6 may be formed by using a heat treatment process, or the Si concentrated layer 6 may be formed by using a thermal history during brazing. However, it goes without saying that after lamination with the core material 2, heat treatment held at 200 ° C. or higher and lower than 400 ° C. should be avoided in order to prevent the high-temperature strength of the core material 2 from decreasing.

The method for laminating the skin material 3 or 4 on the core material 2 is not limited, and may be formed by rolling or by thermal spraying. In the case of thermal spraying, the thermal spraying method is not particularly limited, but an arc sprayer or a flame sprayer using powder may be used. The spraying conditions are not particularly limited, and general spraying conditions may be employed. Further, such spraying may be performed in a non-oxidizing atmosphere such as N ₂ atmosphere or Ar atmosphere in order to prevent oxidation of the sprayed layer formed on the surface of the aluminum material as much as possible.

  For thermal spraying, a method of scanning the spray gun with respect to the work, a method of spraying while unwinding the coiled aluminum core material, or an aluminum core material is extruded when the aluminum core material is an extruded material. It is desirable from the viewpoint of production efficiency that the thermal spraying is performed while extruding from the machine.

  Further, the sprayed layer may be formed only on one surface of the aluminum core material, or the sprayed layers may be formed on both the upper and lower surfaces by performing spraying by arranging spray guns on the upper and lower surfaces of the aluminum core material.

  When the laminated material 1 is processed and used, in order to suppress softening due to recrystallization after brazing, as described above, at least once after the lamination treatment, 400 ° C. or more and 550 ° C. or less, 30 minutes or more and 10 hours or less. You may perform the heat processing of. Moreover, you may give the pre-strain required for the strength fall prevention at the time of brazing. This pre-strain may be applied by processing the laminated material into a predetermined dimensional shape. By setting it as such a process, the ensuring of the moldability (workability) as a tube material and header material of the laminated material 1 and the further improvement of the high temperature strength after a brazing process can be made compatible. Of course, pre-straining may be performed only for the purpose of improving the high-temperature strength after the brazing process, regardless of this purpose. If the pre-strain is an equivalent strain of 0.2% or more and 50% or less, the effect is exhibited.

  FIG. 5 shows that the laminated material 1 is used for the tube 10 and the header 20, the tube 10 is inserted into the insertion hole of the header 20, a plurality of tubes 10 are arranged in parallel, and the tube 10 and the header 20 are made of fluoride. The heat exchanger manufactured by brazing using a flux is shown.

  Core materials or intermediate materials having various compositions A to P shown in Table 1 and skin materials having various compositions 1 to 9 shown in Table 2 were prepared.

[Test 1]
(Examples 1 to 6 in Table 3, Comparative Example 1)
A 400 mm-thick ingot produced by the semi-continuous casting method is hot-rolled and cold-rolled to obtain a cold-rolled plate having a thickness of 1 mm, which is used as a core material. A 1 μm-thick Si spray is applied to both sides of the core, followed by a diffusion treatment at 480 ° C. for 4 h. Thermal spraying using a wire material made of a skin material composition alloy is performed on both surfaces of this laminate, and a skin material having a thickness of 50 μm is laminated to obtain a sample. This sample is held at a heat treatment temperature of 600 ° C. × 1 min.

By such a process, a plurality of samples having material configurations as in Examples 1 to 6 and Comparative Example 1 in Table 3 were manufactured. And the depth and average density | concentration of Si concentration layer of these samples were investigated. Thereafter, a sample was cut into a tensile test shape, and a tensile test at 180 ° C. was performed. Furthermore, a SWAAT 960 hour test was conducted on another sample.
<SWAAT (Synthetic sea Water Acid salt spray Test)>
For the corrosion test, the SWAAT test defined in ASTM-G85-A3 was performed. The test conditions were a corrosion test solution prepared by adding acetic acid to artificial seawater according to ASTM D1141 and adjusted to pH 3, and spraying the corrosion test solution for 0.5 hour-wetting 1.5 hour was one cycle, and this cycle was 960 hours. It was supposed to be implemented.

As an evaluation of the corrosion test, surface observation and cross-sectional observation were carried out with an optical microscope. “◎” indicates that the entire surface corrosion occurred and the depth was 200 μm or less and showed good corrosion resistance. 200 μm or less, intergranular corrosion is “O” when the depth is 150 μm or less, general corrosion or pitting corrosion is that the depth exceeds 200 μm, and intergranular corrosion is that the depth exceeds 150 μm It was set as “x”.
(Comparative Examples 2 and 3)
Samples were prepared in the same steps as in Examples 1 to 6 and Comparative Example 1 except that 1 μm thick Si spraying was not performed, and the depth and average concentration of the Si concentrated layer and the tensile strength at 180 ° C. were determined. In addition to the investigation, a SWAAT 320 hour corrosion test was performed.

  The above results are shown in Table 3.

As can be seen from the results in Table 3, Examples 1 to 6 of the present invention are excellent in both mechanical strength and corrosion resistance, whereas Comparative Examples 1 to 3 in which the core material composition departs from the scope of the present invention are all. It was inferior in strength.
[Test 2]
(Examples 11-22 of Table 4 and Comparative Examples 11-16)
A 300 mm-thick ingot produced by the semi-continuous casting method is hot-rolled to obtain a skin material having a thickness of 20 mm. Furthermore, a skin material is temporarily fixed by welding on both sides of a 400 mm-thick core ingot similarly produced by the semi-continuous casting method, hot-rolled at a starting temperature of 480 ° C., and hot-rolled with a thickness of 10 mm. Get a board. This hot-rolled sheet is heat-treated and then cold-rolled to obtain a cold-rolled sheet having a thickness of 1 mm in which a skin material is laminated on both surfaces of the core material. This sample is subjected to heat treatment at 600 ° C. for 5 minutes.

  By such a process, a plurality of samples having material configurations as in Examples 11 to 22 and Comparative Examples 11 to 16 in Table 4 were manufactured. Table 4 shows the heat treatment conditions of the hot-rolled sheet for each sample.

  And the depth and average density | concentration of Si concentration layer of these samples were investigated.

  Thereafter, a sample was cut into a tensile test shape, and a tensile test at 180 ° C. was performed. Furthermore, a SWAAT 960 hour test was conducted on another sample.

  As an evaluation of the corrosion test, surface observation and cross-sectional observation were carried out with an optical microscope. “◎” indicates that the entire surface corrosion occurred and the depth was 200 μm or less and showed good corrosion resistance. 200 μm or less, intergranular corrosion is “O” when the depth is 150 μm or less, general corrosion or pitting corrosion is that the depth exceeds 200 μm, and intergranular corrosion is that the depth exceeds 150 μm It was set as “x”.

  The results are shown in Table 4.

As can be seen from the results in Table 4, Examples 11 to 22 of the present invention are excellent in both mechanical strength and corrosion resistance, whereas Comparative Example 11 in which the core material composition and / or the skin material composition depart from the scope of the present invention. -16 were inferior to at least one of intensity | strength or corrosion resistance.
[Test 3]
(Examples 31 and 32 in Table 5)
An ingot having a thickness of 300 mm produced by a semi-continuous casting method is hot-rolled to obtain a skin material having a thickness of 20 mm and an intermediate layer material having a thickness of 5 mm. Furthermore, the intermediate material and the skin material are arranged on both sides of the 400 mm-thick core ingot produced by the semi-continuous casting method so that the structure of the skin material / intermediate material / core material / intermediate material / skin material is obtained. Temporarily fixed by welding and hot-rolled at a starting temperature of 480 ° C. to obtain a hot-rolled sheet having a thickness of 10 mm. This hot-rolled sheet is subjected to heat treatment at 450 ° C. for 5 hours, and then cold-rolled to obtain a cold-rolled sheet having a thickness of 1 mm. This sample is subjected to heat treatment at 600 ° C. for 5 minutes.

  By such a process, a sample having a material configuration as shown in Examples 31 and 32 in Table 5 was manufactured. And the depth and average density | concentration of Si concentration layer of these samples were investigated.

  Thereafter, a sample was cut into a tensile test shape, and a tensile test at 180 ° C. was performed. Furthermore, a SWAAT 960 hour test was conducted on another sample.

As an evaluation of the corrosion test, surface observation and cross-sectional observation were carried out with an optical microscope. “◎” indicates that the entire surface corrosion occurred and the depth was 200 μm or less and showed good corrosion resistance. 200 μm or less, intergranular corrosion is “O” when the depth is 150 μm or less, general corrosion or pitting corrosion is that the depth exceeds 200 μm, and intergranular corrosion is that the depth exceeds 150 μm It was set as “x”.
(Examples 33 and 34 in Table 5, Comparative Example 31)
Samples were prepared in the same manner as in Examples 31 and 32 except that no intermediate material was present, and the depth and average concentration of the Si-concentrated layer and the tensile strength at 180 ° C. were examined, and a SWAAT 960 hour corrosion test was performed. Carried out.

  The results are shown in Table 5.

As can be seen from the results in Table 5, Examples 31 to 34 of the present invention are excellent in both mechanical strength and corrosion resistance, whereas Comparative Example 31 in which the core material composition departs from the scope of the present invention has both strength and corrosion resistance. It was inferior.
[Test 4]
(Examples 41 to 46 in Table 6 and Comparative Examples 41 to 44)
An ingot having a thickness of 250 mm produced by a semi-continuous casting method is hot-rolled to obtain a skin material having a thickness of 20 mm. Further, a skin material is temporarily fixed by welding on both sides of a 300 mm thick core ingot produced by the semi-continuous casting method, hot rolled at a starting temperature of 480 ° C., and hot rolled with a thickness of 5 mm. Get a board. The hot-rolled sheet is cold-rolled to obtain a cold-rolled sheet having a thickness of 1.5 mm in which a skin material is laminated on both sides of the core material. This sample is subjected to a heat treatment.

  By such a process, a plurality of samples having material configurations as in the examples and comparative examples in Table 6 were manufactured. Table 6 shows the heat treatment conditions of the cold-rolled plate for each sample.

  And the depth and average density | concentration of Si concentration layer of these samples were investigated. Thereafter, a sample was cut into a tensile test shape, and a tensile test at 180 ° C. was performed. Furthermore, a SWAAT 960 hour test was conducted on another sample.

  As an evaluation of the corrosion test, surface observation and cross-sectional observation were carried out with an optical microscope. “◎” indicates that the entire surface corrosion occurred and the depth was 200 μm or less and showed good corrosion resistance. 200 μm or less, intergranular corrosion is “O” when the depth is 150 μm or less, general corrosion or pitting corrosion is that the depth exceeds 200 μm, and intergranular corrosion is that the depth exceeds 150 μm It was set as “x”.

  The results are shown in Table 6.

  While Examples 41 to 46 of the present invention are excellent in both mechanical strength and corrosion resistance, Comparative Examples 41 to 44 in which the core material composition or the skin material composition departs from the scope of the present invention are inferior in strength and corrosion resistance. Met.

It is sectional drawing of the laminated material which concerns on one Embodiment of this invention. It is sectional drawing of the laminated material which concerns on other embodiment of this invention. It is sectional drawing of the laminated material which concerns on other embodiment of this invention. It is sectional drawing of the laminated material which concerns on other embodiment of this invention. It is sectional drawing which shows an example of the heat exchanger using the laminated material which concerns on one Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Laminated material 2 Core material 3 Skin material 4 Skin material 5 Intermediate material 6 Si concentrated layer 10 Tube 20 Header 30 Heat exchanger

Claims (25)

Si: 1.25 mass% to 2.45 mass%, Fe: 0.15 mass% to 0.8 mass%, Cu: 0.01 mass% to 0.08 mass%, Mn: 1.4 Aluminum containing 0.05% by mass or more and 0.2% by mass or less, Zr; 0.12% by mass or more and 0.3% by mass or less, with the balance being Al and impurities. With the material as the core material,
On at least one surface of the core material, Si: 7.5% by mass to 11.5% by mass, Fe: 0.2% by mass to 0.8% by mass, Cu: 0.005% by mass to 0.35% by mass %, Zn: 0.005 mass% or more and 0.4 mass% or less, and a laminated material for a heat exchanger in which an aluminum skin made of Al and impurities is laminated. Si: 1.25 mass% to 2.45 mass%, Fe: 0.15 mass% to 0.8 mass%, Cu: 0.01 mass% to 0.08 mass%, Mn: 1.4 Aluminum containing 0.05% by mass or more and 0.2% by mass or less, Zr; 0.12% by mass or more and 0.3% by mass or less, with the balance being Al and impurities. With the material as the core material,
On at least one surface of the core material, Si: 7.5% by mass to 11.5% by mass, Fe: 0.2% by mass to 0.8% by mass, Cu: 0.005% by mass to 0.35% by mass %, Zn: 1 mass% or more and 5 mass% or less, The laminated material for heat exchangers by which the aluminum skin | leather which consists of Al and an impurity is laminated | stacked. In the core material, Si: 1.35% by mass or more and 1.65% by mass or less, Fe: 0.3% by mass or more and 0.5% by mass or less, Cu: 0.02% by mass or more and 0.04% by mass or less, Mn: 1.55 mass% or more and 1.75 mass% or less, Ti: 0.08 mass% or more and 0.15 mass% or less, Zr: 0.12 mass% or more and 0.2 mass% or less,
In the skin material, Si: 7.5% by mass to 9.5% by mass, Fe: 0.2% by mass to 0.5% by mass, Cu: 0.005% by mass to 0.3% by mass, Zn: 0.005 mass% or more and 0.3 mass% or less, The laminated material for heat exchangers of Claim 1. In the core material, Si: 1.35% by mass or more and 1.65% by mass or less, Fe: 0.3% by mass or more and 0.5% by mass or less, Cu: 0.02% by mass or more and 0.04% by mass or less, Mn: 1.55 mass% or more and 1.75 mass% or less, Ti: 0.08 mass% or more and 0.15 mass% or less, Zr: 0.12 mass% or more and 0.2 mass% or less,
In the skin material, Si: 7.5% by mass to 9.5% by mass, Fe: 0.2% by mass to 0.5% by mass, Cu: 0.005% by mass to 0.3% by mass, Zn: 1 mass% or more and 2.5 mass% or less, The laminated material for heat exchangers of Claim 2.   The stack for a heat exchanger according to any one of claims 1 to 4, wherein the amount of Mg as an impurity of the core material is limited to 0.04 mass% or less and the amount of Zn as an impurity is limited to 0.08 mass% or less. Wood.   The laminated material for a heat exchanger according to any one of claims 1 to 5, wherein Cr is contained in the core material in an amount of 0.03% by mass or more and 0.25% by mass or less.   The laminated material for a heat exchanger according to any one of claims 1 to 6, wherein Ni is contained in the core material in an amount of 0.05 mass% to 1 mass%.   The laminated material for a heat exchanger according to any one of claims 1 to 7, wherein Sc is contained in the core material in an amount of 0.005 mass% to 0.1 mass%.   As an intermediate layer between the core material and the skin material, Si: 0.05% by mass or more and 2.45% by mass or less, Fe: 0.05% by mass or more and 1.8% by mass or less, Cu: 0.01% by mass 0.3% by mass or less, Mn: 0.05% by mass or more and 2% by mass or less, Ti: 0.01% by mass or more and 0.2% by mass or less, Zn: 0.5% by mass or more and 2.5% by mass or less Zr: Laminated material for heat exchanger according to any one of claims 1 to 8, which is formed by laminating an aluminum material containing 0.005 mass% to 0.3 mass% with the balance being Al and impurities. .   The surface layer of the core material has a Si concentrated layer having a thickness of 50 µm or more and 500 µm or less, and the average Si concentration of the concentrated layer is 1.4 mass% or more and 5 mass% or less. The laminated material for heat exchangers as described in the item. Si: 0.9 mass% or more and less than 1.25 mass%, Fe: 0.15 mass% or more and 0.8 mass% or less, Cu: 0.01 mass% or more and 0.2 mass% or less, Mn: 1.4 Mass% to 2.05 mass%, Ti; 0.05 mass% to 0.2 mass%, Zr; 0.12 mass% to 0.3 mass%, Mg as impurities; 0.04 Mass% or less, Zn; limited to 0.08 mass% or less, with the balance being an aluminum material composed of Al and impurities,
On at least one surface of the core material, Si: 7.5% by mass to 11.5% by mass, Fe: 0.2% by mass to 0.8% by mass, Cu: 0.005% by mass to 0.35% by mass % Or less, Zn: 0.005% by mass or more and 0.4% by mass or less, and a skin material made of an aluminum material made of Al and inevitable impurities is laminated,
And the laminated material for heat exchangers which has Si concentration layer of 50 micrometers or more and 500 micrometers or less in the surface layer of a core material, and also the average Si density | concentration of concentration layer is 1.4 to 5 mass%. Si: 0.9 mass% or more and less than 1.25 mass%, Fe: 0.15 mass% or more and 0.8 mass% or less, Cu: 0.01 mass% or more and 0.2 mass% or less, Mn: 1.4 Mass% to 2.05 mass%, Ti; 0.05 mass% to 0.2 mass%, Zr; 0.12 mass% to 0.3 mass%, Mg as impurities; 0.04 Mass% or less, Zn; limited to 0.08 mass% or less, with the balance being an aluminum material composed of Al and impurities,
On at least one surface of the core material, Si: 7.5% by mass to 11.5% by mass, Fe: 0.2% by mass to 0.8% by mass, Cu: 0.005% by mass to 0.35% by mass %, Zn: 1 mass% or more and 5 mass% or less, The laminated material for heat exchangers by which the aluminum skin | leather which consists of Al and an impurity is laminated | stacked. The heat treatment of at least once, 400 ° C. or more and 550 ° C. or less, and 20 minutes or more and 10 hours or less is performed after the lamination treatment of the core material and the skin material, or the core material, the intermediate layer, and the skin material. The laminate for a heat exchanger according to any one of 10. The laminated material for a heat exchanger according to claim 13, wherein the heat treatment is 400 ° C or higher and 500 ° C or lower and 30 minutes or longer and 8 hours or shorter. A tube for a heat exchanger, comprising the laminated material according to any one of claims 1 to 4, or 11 or 12, wherein a skin material in the laminated material is formed by a thermal spraying method. Wood. A tube material for a heat exchanger, comprising the laminated material according to claim 9, wherein an intermediate material in the laminated material is formed by a thermal spraying method. It consists of the laminated material of Claim 10 or Claim 11, and Si concentration layer in the said laminated material coat | covers the outer peripheral part of a tube main body with the Al-Si type alloy by a thermal spraying method, and also heat diffusion after that. It is formed by making it the tube material for heat exchangers characterized by the above-mentioned. A tube material for a heat exchanger, comprising the laminated material according to claim 13 or 14, wherein a pre-strain of 0.2% or more and 50% or less is given as an equivalent strain after the heat treatment. A header for a heat exchanger, comprising the laminated material according to any one of claims 1 to 4 or 11 or 12, wherein a skin material in the laminated material is formed by a thermal spraying method. Wood. A header material for a heat exchanger, comprising the laminated material according to claim 9, wherein an intermediate material in the laminated material is formed by a thermal spraying method. It consists of the laminated material of Claim 10 or Claim 11, and Si concentration layer in the said laminated material coat | covers the outer peripheral part of a header main body with the Al-Si type alloy by a thermal spraying method, and also heat diffusion after that. It is formed by making it the header material for heat exchangers characterized by the above-mentioned. A header material for a heat exchanger, comprising the laminated material according to claim 13 or 14, wherein a pre-strain of 0.2% to 50% is given as an equivalent strain after the heat treatment. The laminated material for a heat exchanger according to any one of claims 1 to 9 is used as a heat exchanger constituent member, and the constituent member is brazed using a fluoride-based flux, whereby the surface layer of the core material is thickened. A method for producing a heat exchanger, wherein a Si concentrated layer having a thickness of 50 μm or more and 500 μm or less is formed, and the average Si concentration of the concentrated layer is 1.4 mass% or more and 5 mass% or less. The heat exchanger produced by using the tube material as described in any one of Claims 15-18. The heat exchanger produced by using the header material as described in any one of Claims 19-22.

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