Widespread use of aluminum alloys for the fabrication of car body parts is conditional to the use of appropriate welding methods, especially if dissimilar welding must be performed with automotive steel grades. Friction stir welding (FSW) is considered to be a reasonable solution to obtain sound aluminum-steel joints. In this context, this work studies the effects of tool position and force control in dissimilar friction stir welding of AA6061 aluminum alloy on DC05 low carbon steel in lap joint configuration, also assessing proper welding parameter settings. Naked eye and scanning electron microscopy (SEM) have been used to detect macroscopic and microscopic defects in joints, as well as to determine the type of intermixture between aluminum and steel. The joint strength of sound joints has been assessed by shear tension test. Results point out that tool force control allows for obtaining joints with better quality and strength in a wider range of process parameters. A process window has been determined for tool force conditions to have joints with adequate strength for automotive purposes.

中文翻译：

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位置和力工具控制在汽车用异种铝钢搭接接头的摩擦搅拌焊接中的作用

铝合金在车身零件制造中的广泛使用取决于使用适当的焊接方法的条件，特别是如果必须对汽车钢种进行不同的焊接时。搅拌摩擦焊（FSW）被认为是获得良好铝钢接头的合理解决方案。在这种情况下，这项工作研究了AA6061铝合金在搭接接头配置下的DC05低碳钢的异种摩擦搅拌焊接中刀具位置和力控制的影响，还评估了适当的焊接参数设置。裸眼和扫描电子显微镜（SEM）已用于检测接头的宏观和微观缺陷，并确定铝和钢之间的混合类型。健全接头的接头强度已通过剪切张力测试进行了评估。结果表明，工具力控制可以在更广泛的工艺参数范围内获得质量和强度更高的接头。已经确定了用于工具力条件的工艺窗口，以使接头具有足够的强度以用于汽车用途。