6mm厚货车用铝合金板摩擦搅拌焊试验研究

摩擦搅拌焊技术已成为铝合金焊接的重要手段。针对5052和6061-T6两种6 mm厚铁路货车使用的铝合金板材,采用摩擦搅拌焊设备进行焊接试验;并进行了相关检测,研究不同工艺参数对焊接质量的影响。结果表明:提高搅拌头的转速和降低焊接速度有利于降低设备的主轴轴向受力。在低转速时,摩擦搅拌焊的焊接质量较差,焊缝结构疏松,容易出现焊缝缺陷;当转速提高到1 200 r/min时,热输入能量适中,焊缝表面光滑明亮,表观质量良好。由焊缝表观可以发现,提高焊接进给速度后,焊缝表面光亮度下降,纹路变得明显,表面变得粗糙;在较高的搅拌头转速下以不同焊接速度进行焊接,其焊缝内部基本无可见缺陷,质量良好;在相同的搅拌头转速和焊接速度下,6061-T6铝合金板焊接过程中主轴压力略低于5052铝合金板。

Research on Friction Stir Welding Test of 6mm Thick Aluminum Alloy Plate Used for Railway Wagons

Friction stir welding technology has become an important method for aluminum alloy welding. The friction stir welding equipment is utilized to do experiments on 6mm thick 5052 and 6061-T6 aluminum alloy plate used for railway wagons and coherent detection is carried out to research on the effect of different parameters on the welding quality. The results are shown as followings. Improving the rotational speed and reducing the welding speed of the mixing head could reduce the axial pressure of the the equipment. At low rotational speed, the welding quality is poor, welding seam structure is loose, and weld defects are prone to occur. When the rotational speed is increased to 1200r/min, heat input energy is moderate and the weld surface is smooth and bright, which indicates that the apparent quality is good. It could be found from the weld appearance that, with the welding speed increasing, the weld surface becomes dull and rough with obvious lines. Under the high rotational speed of stirring head, there are no visible defects in the welding seams which are welded with different welding speed, and the quality is good. At the same rotational speed and welding speed, the main axle pressure of 6061-T6 aluminum alloy plate is slightly lower than that of 5052 aluminum alloy plate during welding process.