Improving arc joining of Al to steel and Al to stainless steel
Improving arc joining of Al to steel and Al to stainless steel
复制标题
改善铝与钢和铝与不锈钢的电弧连接
DOI：
10.1016/j.msea.2011.11.090
复制
发表时间：
2012-02-01
期刊：
影响因子：
6.4
通讯作者：
Kou, Sindo
中科院分区：
文献类型：
--
作者：
Dong, Honggang;Yang, Liqun;Kou, Sindo
控制热输入的钨极气体保护焊(GTAW)可以避免铝-钢异种金属连接在凝固过程中形成大量脆性Al-Fe金属间化合物。在本研究的第一部分，采用铝硅填充气体保护焊将铝镁合金连接到镀锌钢上。结合Al-Mg-Si相图对焊缝凝固组织进行了解释。GTAW过程中的超声振动使接头强度提高了27%。在热影响区和焊缝中观察到晶粒细化，Fe-Al金属间化合物减少，显微硬度增加，从而解释了接头强度的提高。在第二部分中，使用带非腐蚀性药芯的锌-15Al钎料将铝镁合金连接到304不锈钢上。结合Al-Zn-Mg相图对焊缝凝固组织进行了解释。焊后热处理(PWHT)在280℃下进行30分钟，可使接头强度增加一倍甚至三倍，具体取决于铝板厚度。热处理后，粗大的富锌颗粒在焊缝/钢界面上溶解，从而消除了界面上的这些弱颗粒。根据Al-Fe-Zn相图解释了界面附近富锌颗粒的形成和热处理后富锌颗粒的溶解。(C)2011爱思唯尔B.V.保留所有权利。
Gas-tungsten arc welding (GTAW) with controlled heat input could avoid the formation of massive brittle Al-Fe intermetallics during solidification in dissimilar-metal joining of aluminum to steel. In the first part of the present study an Al-Mg alloy was joined to galvanized steel by GTAW with an Al-Si filler metal. The weld solidification microstructure was explained based on the Al-Mg-Si phase diagram. Ultrasonic vibration during GTAW increased the joint strength by 27%. Grain refinement, decreased Fe-Al intermetallics, and increased microhardness in both the heat-affected zone and the weld were observed, thus explaining the improved joint strength. In the second part, an Al-Mg alloy was joined to 304 stainless steel using a Zn-15Al filler metal with a noncorrosive flux core. The weld solidification microstructure was explained based on the Al-Zn-Mg phase diagram. Postweld heat treatment (PWHT) at 280 degrees C for 30 min doubled or even tripled the joint strength depending on the Al-sheet thickness. Dissolution of coarse Zn-rich particles at the weld/steel interface was observed after PWHT, thus eliminating these weak particles from the interface. The formation of Zn-rich particles near the interface and their dissolution by PWHT were explained based on the Al-Fe-Zn phase diagram. (C) 2011 Elsevier B.V. All rights reserved.