Al-Mg合金间隙脉冲焊修工艺

Pulsed Welding Repairing Technology of Al-Mg Alloys

针对普通脉冲氩弧焊焊接铝合金存在温度高、热变形大的问题,研发了间隙交流脉冲氩弧焊焊修工艺,并进行了试验,测试分析了堆焊层及热影响区的显微硬度、显微组织以及焊缝上标定点及试板中局部区域的温度场分布。结果表明,热影响区宽度随焊接电流的增大而增大,焊接热量输入也增多。在相同电流条件下,间隙脉冲焊接热量累积较少,热影响区小,晶粒相对细小,硬度值相对较高。与连续脉冲焊接相比,间隙脉冲焊修工艺作用到基体上的能量比较少,相对比较集中,热量累积较少,使整个热影响区的温度上升比较平缓,温度较低,晶粒相对细小,堆焊层及热影响区硬度高。

An experimental investigation of ac pulsed argon arc welding of the Al-Mg alloy was carried out under the condition of the defects of the high temperature and thermal deformation. The Vickers microhardness profiles were measured by microhardness tester. The temperature of the calibration point was examined by FlirA20. And the microstructure of the welded joints was examined by means of Olympus optical. The experiment results show that the width of HAZ in- creases while the current increases and welding heat input increases. In the same current conditions, the pulsed welding heating heat accumulation become less, the microstructure is better and the microhardness become higher. Compared with argon arc welding, the energy on the Al-Mg alloy is lesser, and relatively concentrated, which make the temmereture of the whole HAZ rises slowly. It was effective to resist the less heat accumulation,the better microstructure and the higher microhardness of the clad layer and HAZ.