Denso Corporation

Sumitomo Light Metal Industries, Ltd.

Other

Koji Hirao

Yasunaga Itoh

Hiroshi Ikeda

Yoshiharu Hasegawa

Yuji Hisatomi

Hiroshi Nishikawa

Hirokazu Tanaka

Yuji Suzuki

Hiroshi Ogawa

Naoki Yamashita

Shoei Teshima

Taketoshi Toyama

Yoshifusa Shoji

Haruhiko Miyachi

Takahiro Koyama

Satoshi Nohira

Eiichi Kashima

Takashi Hatori

Shinichi Tani

Takanori Takeda

Syoji Iriyama

Keiichi Sakai

The present invention provides an aluminum alloy fin material for heat exchangers which has a thickness of 80 &#x3bc;m (0.08 mm) or less and excels in joinability to a tube material and in intergranular corrosion resistance. The aluminum alloy fin material is an aluminum alloy bare fin material or a brazing fin material which has a thickness of 80 &#x3bc;m or less and is incorporated into a heat exchanger made of an aluminum alloy manufactured by brazing through an Al&#x2014;Si alloy filler metal. The structure of the core material before brazing is a fiber structure, and the crystal grain diameter of the structure after brazing is 50&#x2013;250 &#x3bc;m. The Si concentration in the Si dissolution area on the surface of the fin material and at the center of the thickness of the fin material after brazing is preferably 0.8% or more and 0.7% or less, respectively.

Aluminum alloy fin material for heat exchangers and heat exchanger including the fin material

An object of the present invention is to provide a filler metal for an aluminum brazing sheet for heat exchangers capable of preventing or controlling occurrence of a melting hole during heating for brazing, and a method of manufacturing the same. In an Al&#x2014;Si alloy filler metal which is clad on the aluminum brazing sheet and melted during heating for brazing, the maximum particle diameter of a coarse Si particle crystallized in the eutectic structure of the filler metal is 20 &#x3bc;m or less. Provided that an average value and a standard deviation in a normal distribution of the particle diameter of the coarse Si particle in the filler metal are respectively &#x3bc; and &#x3c3;, (&#x3bc;+3&#x3c3;) is preferably 10 &#x3bc;m or less. This brazing sheet is obtained by a method of adding a specific amount of Na, Sr, or Sb to the filler metal, a method of limiting the amount of impurities in the filler metal within a specific range, a method of specifying a cooling rate during the casting of the filler metal, or the like.

Filler metal for aluminum brazing sheet for heat exchangers and method of manufacturing same

In a manufacturing method of a heat exchanger including a core portion having a plurality of tubes and a plurality of radiation fins connected to surfaces of the tubes, and a tank portion communicating with the tubes, a preheating step, a brazing step, a gradual cooling step and a cooling step are performed in this order. In the preheating step, temperature of the tank portion having a large heat capacity is increased earlier than that of the core portion having a small heat capacity. Therefore, the temperature of the tank portion is rapidly increased, and the temperature of the core portion is obediently increased in accordance with the temperature increase of the tank portion.

Manufacturing method of heat exchanger

A brazing composition for aluminum materials capable of functioning as a flux and a brazing material with a single component and providing a solid brazed joint exhibiting little local fusion. The brazing composition for aluminum materials which has the function of removing the oxide film on the surface of the aluminum material to be joined at a temperature lower than the melting point of the aluminum material and forming a eutectic aluminum alloy braze which fuses at such a low temperature by reaction with the aluminum materials, wherein the brazing composition comprises a first powder comprising at least one or more M&mdash;Si&mdash;F compounds comprising, in addition to at least Si and F, hydrogen or an alkaline metal or hydrates thereof or comprises this first powder as an component.

Brazing composition for aluminum material, aluminum material for brazing, and method of brazing aluminum material

A brazing sheet which has an excellent corrosion resistance and cladding rolling property, and is formed from a four layer aluminum alloy cladding member, and a heat exchanger of aluminum alloy, in which the brazing sheet is used, are provided. The brazing sheet is suitable for use as a member in the fluid path of an aluminum heat exchange for a car, and particularly, as a core plate of a drawn cup type heat exchanger. In the brazing sheet, one side of a core member is cladded with an intermediate member less noble than a core member, and the other side of both the core member and the intermediate member are cladded with Al--Si--Mg type cladding member, wherein the core member is of an aluminum alloy containing 0.5 to 1.6% of Mn, 0.15 to 0.35% of Cu, 0.05 to 0.50% of Mg, 0.06 to 0.30% of Ti, and the remainder being Al and unavoidable impurities, and the intermediate member contains 0.5 to 1.2% of Mn and the remainder being aluminum and unavoidable impurities, and 0.05 to 1.2% of Mg, if desired, and has a 70 to 130% deformation resistance. The intermediate member may be composed of an aluminum alloy containing 1 to 5% of Zn, 0.5 to 1.2% of Mg, and the remainder being Al and unavoidable impurities.

Brazing sheet having an excellent corrosion resistance for use in a heat

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Nishio, Japan

Koji Hirao