JPS6089540A - Aluminum alloy for fin of heat exchanger - Google Patents

Abstract

PURPOSE:To obtain an Al alloy for fins producing a significant sacrificial anode effect by adding a proper amount of Ca or Li to an Al-Mn-Zn-Sn alloy having a specified composition. CONSTITUTION:This Al alloy for the fins of a heat exchanger consists of, by weight, 0.5-2.0% Mn, 0.5-2.0% Zn, 0.02-0.1% Sn, 0.05-1.0% in total of Ca and/or Li and the balance Al with inevitable impurities. By this alloy composition, the potential of the fins is made lower than that of the tube, so the fins act as a sacrificial anode to prevent the corrosion of the tube in any corrosive environment. The alloy produces a significant sacrificial anode effect as the material of the fins of a heat exchanger made of an Al alloy especially when vacuum brazing is applied.

Description

【発明の詳細な説明】 本発明は熱交換器のフィン用アルミニウム合金に関する
もので、特に真空ろう（＝Ｉけにより構成するＡ（合金
製熱交換器のフィンとして、優れた犠牲陽極効果を有す
るものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an aluminum alloy for the fins of a heat exchanger, and in particular, an aluminum alloy made of vacuum solder (=I) (which has an excellent sacrificial anode effect as a fin of an alloy heat exchanger). It is something.

一般に熱交換器、例えは自動車用ラジェーターに（よＣ
１ｌ又はＣｕ合金が用いられていたが、最近軽量化及び
コス１へダウンの目的で／ｌ含金がかなり用いられるよ
うになってきた。このような熱交換器のコアーは水を通
すデユープと熱を放散するフィンからなり、Ａｆ合金製
熱交換器では通常厚さ０．１０〜０．１３ｍｍの板材を
コルゲート状に加工したフィンと、電Ｒ？１ｆ！　番偏
平に加工したチューブを組合せ、密着性を良くするため
鉄製冶具で挾持して真空ブレージングすることによりコ
アーを製造している。Heat exchangers are generally used in automobile radiators (YoC).
1L or Cu alloys have been used, but recently, /L alloys have come to be used considerably for the purpose of reducing weight and reducing the cost to 1. The core of such a heat exchanger consists of a duplex that allows water to pass through and fins that dissipate heat. Af alloy heat exchangers usually have fins that are made from a plate material with a thickness of 0.10 to 0.13 mm that is processed into a corrugated shape. Electric R? 1f! The core is manufactured by combining flattened tubes, clamping them with iron jigs and vacuum brazing them to improve adhesion.

フィンに（まＡｆｆｌ−Ｍｎ系合金、例えばＡ、ｆ２−
０．１５〜ｖｔ％（：ｌＩ（以下ｗｔ％を単に％と略記
）−１，１％Ｍｎ合金（Ａ　３００３）や７’Ｊ−１，
１％ｌｙｌ　ｎ合金（Ａ３２０３　）を用い、電縫管（
チューブ）には上記合金（Ａ　３００３、Ａ３２０３　
）を芯材とし、その片面にＡＺ−Ｓ＊系合金からなるろ
う材、例えばＡｆ−１０％３ｉ−１，５％ＭＯ合金（Ａ
　４００４　）や／Ｊ−１０％３ｉ−１，５％ＭＯ−０
，１％Ｂ１合金＜Ａ４１０４）をクラットしたブレージ
ングシー１〜が用いられ′Ｃいる。On the fins (or Affl-Mn alloys, such as A, f2-
0.15~vt% (:lI (hereinafter wt% is simply abbreviated as %)-1,1%Mn alloy (A 3003), 7'J-1,
Using 1% lyl n alloy (A3203), electric resistance welded tube (
The above alloys (A 3003, A3203
) as a core material, and one side of the core material is a brazing material made of AZ-S* alloy, for example, Af-10%3i-1,5% MO alloy (A
4004) Ya/J-10%3i-1,5%MO-0
, 1% B1 alloy <A4104) is used.

このような八ぶ合金製熱交換器は実際の使用において、
外部及び内部からの腐食が問題になっている。特に外部
については走行中に塩分又は塩分を含む泥や砂が付着す
ることがあり、これ等が付着すると付着部から腐食が発
生し、八ぶ合金特有の貫通孔食を起し、熱交換器の機能
を損なうことが度々生じている。通常デユープの外面は
３ｉ　リッチのＡ（合金となっており、電位の高いＳｌ
とその周辺にある電位の低いα相との間に局部電池が形
成し易く、一般のＡ（合金より腐食が早く進行する傾向
があり、その改善が強く望まれている。In actual use, such a Yabu alloy heat exchanger
Corrosion from the outside and inside is a problem. Particularly on the outside, salt or salt-containing mud or sand may adhere to the exterior during driving, and if this adheres, corrosion will occur from the adhered parts, causing through-pitting corrosion unique to Yabu alloys, and causing damage to the heat exchanger. This often results in loss of functionality. Normally, the outer surface of the duplex is made of 3i-rich A (alloy, and has a high potential of Sl).
A local battery is likely to form between the aluminum alloy and the surrounding α-phase with a low potential, and corrosion tends to progress more quickly than general A (alloy), so improvement of this problem is strongly desired.

本発明はこれに鑑み外部の耐食性に及ぼす諸因子につい
て種々検器の結果、Ａ（にＭｎ　、　Ｚｎ　。In view of this, the present invention has determined the results of various tests on various factors that affect external corrosion resistance.

Ｓｎと更にＣａ又は／及びｌｉを添加することにより、
フィンどしての電位をデユープの電位より４−分低くし
、いかなる腸食環境においでもフィンが犠牲陽極となっ
てチューブを防食することを知見し、更に検討の結果真
空ろう伺けにより構成する／１合金製熱交換器のフィン
どして優れ１〔犠牲陽極効果を有する熱交換器のフィン
用アルミニウム合金を開発したもので、Ｍｌｌｏ、５〜
２．０％、ＺｎＯ１５〜２．０％、Ｓ００．０２〜０．
１％と、更にＣａ、ｌｉの何れか１種又は２種を合計０
．０５〜１．０％とを含み、残部へ（と不可避的不純物
からなることを特徴とづるものである。By adding Sn and further Ca or/and Li,
The potential at the end of the fin was set 4 minutes lower than the potential at the duplex, and it was discovered that the fin acts as a sacrificial anode to protect the tube from corrosion in any enteric environment.As a result of further study, it was constructed using vacuum solder. /1 Excellent as alloy heat exchanger fins 1 [Developed aluminum alloy for heat exchanger fins with sacrificial anode effect, Mllo, 5~
2.0%, ZnO15-2.0%, S00.02-0.
1% and one or both of Ca and Li in total of 0
．． 05 to 1.0%, with the remainder consisting of unavoidable impurities.

しかして本発明において、Ｍ１１添加はＡヌ含金の強度
を向上させると共にろうイ」け時のフィンの座屈を防止
するためで、その含有ｍを０．５〜２．０％と限定した
のは、０．５％未満では上記効果、特にフィンの座屈防
止に対して効果が顕著でなく、２．０％を越えると巨大
なＡＪ！−Ｍｎ化合物が生成し塑性加工性を阻害するた
めである。However, in the present invention, the addition of M11 is to improve the strength of the A-containing metal and to prevent buckling of the fin during soldering, and the content of M11 is limited to 0.5 to 2.0%. The reason is that if it is less than 0.5%, the above effects, especially in preventing fin buckling, will not be noticeable, and if it exceeds 2.0%, it will cause a huge AJ! This is because -Mn compounds are generated and inhibit plastic workability.

Ｚ　１１及び３ｎの添加はＡ（合金の電位を下げ、チュ
ーブに対で犠牲陽極とすることにより、チューブを陰極
防食するもので、特にＺ’　ｒ＋及びＳｎを共存さゼる
ことにより上記効果を安定化させたものであり、７ｎ含
有量を０．５〜２．０％と限定したのは０．５％未満で
は上記効果が得られず、２．０％を越えるとＡ℃金合金
融点を下げ、ろうイ」り時にフィンが座屈し易くなるた
めである。またＳｎ含有ｍを０．０２〜０．１％と限定
したのは、０．０２％未満では上記効果が得られず、０
．１％を越えると塑性加工性が低下し、特に熱間圧延時
に鋳塊割れが発生し易くなるためである。The addition of Z 11 and 3n provides cathodic protection for the tube by lowering the potential of the alloy (A) and serving as a sacrificial anode in the tube. In particular, the coexistence of Z' r+ and Sn improves the above effect. The reason why the 7n content is limited to 0.5-2.0% is that if it is less than 0.5%, the above effect cannot be obtained, and if it exceeds 2.0%, the A℃ gold alloy alloy is This is because the Sn content is limited to 0.02 to 0.1% because the above effect cannot be obtained with less than 0.02%. ,0
．． This is because if it exceeds 1%, plastic workability decreases, and cracks in the ingot are likely to occur particularly during hot rolling.

Ｃａ又は／及びｌｉの添加は真空ろう付は時にＺ＋１の
魚介を抑制すると共にＡ（合金の電位を更に不けて犠牲
陽１へ効栄を向上させるためで、これ等の内１種又は２
種の合計含有吊を０．０５〜１．０％と限定したのは、
０．０５％未満では上記効果が得られず、１．０％を越
えるとＡＪ２合金の溶解、鋳造時に酸化し易く、不健全
な鋳塊となり、圧延加工時に割りなどの欠陥を生じ易く
なるためである。The addition of Ca or/and Li is sometimes used in vacuum brazing to suppress Z+1 seafood and to further lower the potential of the alloy to improve the effectiveness of sacrificial positive 1.
The reason why the total content of seeds was limited to 0.05-1.0% was because
If it is less than 0.05%, the above effects cannot be obtained, and if it exceeds 1.0%, the AJ2 alloy will be easily oxidized during melting and casting, resulting in an unhealthy ingot, which will easily cause defects such as cracks during rolling. It is.

尚、不可避的不純物とは通常の八（地金に含まれる不純
物である。Incidentally, unavoidable impurities are the usual 8 (impurities contained in the base metal).

以下本発明を実施例について詳細に説明づ゛る。The present invention will now be described in detail with reference to embodiments.

第１表に示す組成の合金を常法に従って溶製し、水冷鋳
造した。得られた鋳塊を５５０℃の湿度で３時間均質化
処理した後、表面を面削して厚さ４００ｍｍとし、これ
を５００°Ｃの温度に再加熱して熱間圧延により厚さ５
　ｍｍの板とし、更に冷間圧延により厚さ０．１４ｍｍ
の板とした。これを３６０°Ｃの温度で２時間焼鈍した
後、冷間圧延により厚さ０．１１ｍｍとし、スリッター
により巾３２　ｍｍの条とした。Alloys having the compositions shown in Table 1 were melted according to conventional methods and water-cooled and cast. After the obtained ingot was homogenized at 550°C humidity for 3 hours, the surface was chamfered to a thickness of 400mm, which was then reheated to a temperature of 500°C and hot rolled to a thickness of 5mm.
mm plate and further cold-rolled to a thickness of 0.14 mm.
It was made into a board. This was annealed at a temperature of 360° C. for 2 hours, then cold rolled to a thickness of 0.11 mm, and slittered to a width of 32 mm.

この条材を高さ１２　ｍｍ、ピッチ３　ｍｍのコルゲー
ト状フィンに加工し、このフィンとｌ］１３，２ｍｍ、
高さ２．５ｍｍ、板厚０．４ｍｍの電縫偏平チューブ（
芯材Ａ３００３、ろう４ΔＡ４１０４）とを第１図に示
すように電縫偏平チューブ（１〉とフィンく２）を交互
に積層し、冶具で固定し、真空（５ｘ１０　５１−ｏｒ
ｒ　）中６００°Ｃの温度で３分間加熱してろう何けし
、模凝二１７−を製造してフィンの座屈状態を調べた。This strip was processed into corrugated fins with a height of 12 mm and a pitch of 3 mm.
ERW flat tube with a height of 2.5 mm and a plate thickness of 0.4 mm (
Core material A3003, solder 4ΔA4104) and ERW flat tubes (1> and fins 2) were stacked alternately as shown in Figure 1, fixed with a jig, and vacuumed (5x10 51-or
r) was heated for 3 minutes at a temperature of 600° C. to produce a model fin No. 17-, and the buckling state of the fin was examined.

またこの模擬コアーについてフィンの犠牲陽極効果を確
認づ゛るため、塩水噴霧Ｌｌｌ　Ｓ　−２２３７１）中
に６ケ月放置した後、チューブに発生した孔食深さを測
定した。In addition, in order to confirm the sacrificial anode effect of the fins on this simulated core, the depth of pitting corrosion that occurred in the tube was measured after being left in salt water spray LllS-22371) for 6 months.

尚、参考のため真空ろうイ」（プ後、５％Ｎａ　Ｃ，ｅ
溶液（液温２５°Ｃ）中で飽和ノＪロメル電極を基準と
してフィンの電位を測定した。これ等の測定結果を第１
表にイノ（記した。In addition, for reference, 5% Na C, e
The potential of the fin was measured in a solution (liquid temperature: 25°C) using a saturated J Romel electrode as a reference. These measurement results are the first
Ino (written) on the table.

ｉ　＜ｍ’＝ｂｂ””””””””　。i<m’=bb””””””””.

５ Ｚ　ｗ（％Ｊ（ＱｑｔＬｌ’）■トのｃｒ＋＝、−−−
−−、−、−第１表から明らかなように本発明合金Ｎ０
．１−１０からなるフィン側は電位−７８０−一−９０
０７１１，Ｖであり、チ」−ブの電位−７００７ｒＬＶ
と比較し、８０ＴｎＶ以上も低く、デユープの最大孔食
深さも０．０４〜０．０９ａ＋ｍと何れもｏ、’＋ｍｍ
以下であり、フィンの犠牲陽極効果により十分に陰極防
食されてＪ３す、フィンどしての耐座屈性も良好である
ことが判る。5 Z w(%J(QqtLl')■t's cr+=, ---
--,-,-As is clear from Table 1, the alloy of the present invention N0
．． The fin side consisting of 1-10 has a potential of -780-1-90
0711,V, and the potential of the chip is -7007rLV.
Compared to that, it is lower than 80TnV, and the maximum pitting depth of the duplex is 0.04 to 0.09a+m, both o and '+mm.
It can be seen that the fins have sufficient cathodic protection due to the sacrificial anode effect and the buckling resistance of the fins is also good.

これに対し本発明合金の組成範囲より外れる比較合金で
は犠牲陽極効果が不十分でデユープの最大孔食深さが０
．１ｍｍ以上となるか、又は耐座屈性が劣ることが判る
。即ちＭ　１１含有量の少ない比較合金Ｎｏ、１１、Ｚ
ｎ含有予の多い比較合金Ｎｏ、１３で（ま伺れも耐座屈
性が低下し、Ｚ　ｎ含有ｆｊｊの少ない比較合金ＮＯ，
１２，３ｎ含右量の少ない比較合金Ｎ（＋、１４、Ｃａ
又は／及びｌｉ金含有ｎの少ない比較合金Ｎｏ、＋５〜
１６では何れら犠牲陽極効果が不十分でデユープの最大
孔食深さが０．１ｍｍ以上どなっている。On the other hand, in comparison alloys outside the composition range of the present alloy, the sacrificial anode effect is insufficient and the maximum pitting depth of the duplex is 0.
．． It can be seen that the buckling resistance is 1 mm or more, or the buckling resistance is poor. That is, comparative alloys No. 11 and Z with low M 11 content
Comparative alloy No. 13, which contains a lot of n, has a lower buckling resistance, and comparative alloy No. 13, which has a small amount of Z
Comparative alloy N(+, 14, Ca
Or/and Comparative alloy No. with less li gold content n, +5~
In No. 16, the sacrificial anode effect was insufficient and the maximum pitting depth of the duplex was 0.1 mm or more.

尚、Ｍ１１含有量の多い比較合金、３ｎ含有但の多い比
較合金、Ｃａ又は／及びｌｉ含有但の多い比較合金は何
れも加工性が悪く、フィン側には適さないため、上記緒
特性の測定を省略した。In addition, the comparative alloys with a high M11 content, the comparative alloys with a large 3n content, and the comparative alloys with a large Ca or/and li content all have poor workability and are not suitable for fins, so the above characteristics were measured. was omitted.

このように本発明合金にＪ、れば真空ろうイ」（ブによ
り構成する八ぶ合金製熱交換器のフィンとして、デユー
プに苅り−る犠牲陽極効果が侵れ、チューブを有効に陰
極防食し、熱交換器の耐用年数を向上し得る顕著な効果
を奏Ｊるものである。In this way, if the alloy of the present invention is used as a fin of a heat exchanger made of a vacuum solder, the sacrificial anode effect applied to the duplex will be eroded, effectively protecting the tube from cathodic corrosion. This has a remarkable effect of improving the service life of the heat exchanger.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図はＡ柔合金製熱交換器の試験用模擬コアーの一例
を示す斜視図である。 １、　電１偏平デユープ ２　、　フ　ィ　ン 第１図FIG. 1 is a perspective view showing an example of a test simulation core of a heat exchanger made of A soft alloy. 1.Electrical 1.Flat duplex 2.Fin Figure 1

Claims (1)

【特許請求の範囲】[Claims] Ｍ１＋　０．５〜２．Ｏｗ１％、Ｚ　Ｉｔ　０．５〜２
．Ｏｗｔ％、Ｓ　ｎ　Ｏ，０２〜０．ｉｗｔ％ど、更に
Ｃａ、ｌ−ｉの何れか１種又は２種を合泪０，０５〜１
．０〜ｖｔ％とを含み、残部／ｌと不可避的不純物から
なる熱交換器のフィン用アルミニウム合金。M1+ 0.5-2. Ow1%, Z It 0.5~2
．． Owt%, S n O, 02-0. iwt%, and further any one or two of Ca, l-i, 0.05 to 1
．． An aluminum alloy for fins of a heat exchanger, containing 0 to 5% by volume and the balance/l consisting of unavoidable impurities.