ALUMINUM BRAZING SHEET

• Main Authors: TANIGUCHI KENICHI, YOSHINO MICHIHIDE, MATSUSHITA AKIRA, MIYAKE HIDEYUKI, ITO MASATO
• Format: Patent
• Language: English; Japanese
• Published: 11.10.2021
• Subjects: ALLOYS; CHEMISTRY; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; FERROUS OR NON-FERROUS ALLOYS; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; METALLURGY; PERFORMING OPERATIONS; SOLDERING OR UNSOLDERING; TRANSPORTING; TREATMENT OF ALLOYS OR NON-FERROUS METALS; WELDING; WORKING BY LASER BEAM

To provide an appropriate aluminum brazing sheet used for flux free brazing.SOLUTION: An aluminum brazing sheet contains 0.01 to 2.0 mass% Mg, 1.5 to 14.0 mass% Si, and 0.005 to 1.5 mass% Bi. Furthermore, in a thermodynamic calculation, an Al-Si-Mg-Bi-based brazing material that contains at least one or more kinds of additional element of 0.01 or more mass% and 0.5 or less mass% satisfying the following formula (1), and in which the total content of the one or more kinds of additional element including any other inevitable impurity elements is included in a range of 0.05 or more mass% and 1.5 or less mass%, is located on the outermost surface of the brazing sheet. Coarse Si particles included in the brazing material, which have a long side whose length is 50 μm or more in a viewing direction of a front layer surface (RD-TD) are 10 particles per as 1000000 μm2. The formula (1) is γx<γ0 and γ3x<1.002×γx.SELECTED DRAWING: Figure 1 【課題】本発明はフラックスフリーろう付け用に用いて好適なブレージングシートの提供を目的とする。【解決手段】本発明は、質量％で、Ｍｇを０．０１〜２．０％、Ｓｉを１．５〜１４．０％、Ｂｉを０．００５〜１．５％含有し、さらに熱力学計算において、以下の式（１）を満たす０．０１質量％以上０．５質量％以下の添加元素を少なくとも１種類以上含有し、前記１種類以上の添加元素の合計含有量がその他不可避不純物元素を含めて０．０５質量％以上１．５質量％以下の範囲で含まれるＡｌ−Ｓｉ−Ｍｇ−Ｂｉ系ろう材が、ブレージングシート最表面に位置し、前記ろう材に含まれ、表層面（ＲＤ−ＴＤ）方向の観察による長辺の長さが５０μｍ以上である粗大Ｓｉ粒子が、１００００００μｍ２あたり１０個以下である。γｘ＜γ０、かつ、γ３ｘ＜１．００２×γｘ...式（１）【選択図】図１