Continuous-drive rotary friction welding was performed to join cylindrical specimens of carbon steel (EN24) and nickel-based superalloy (IN718), and the microstructures of three distinct weld zones—the weld interface (WI)/thermo-mechanically affected zone (TMAZ), the heat-affected zone (HAZ), and the base metal—were examined. The joint was observed to be free of defects but featured uneven flash formation. Electron backscatter diffraction (EBSD) analysis showed substantial changes in high-angle grain boundaries, low-angle grain boundaries, and twin boundaries in the TMAZ and HAZ. Moreover, significant refinement in grain size (2–5 μm) was observed at the WI/TMAZ with reference to the base metal. The possible causes of these are discussed. The microhardness profile across the welded joint shows variation in hardness. The changes in hardness are ascribed to grain refinement, phase transformation, and the dissolution of strengthening precipitates. The tensile test results reveal that a joint efficiency of 100% can be achieved using this method.

进行了连续驱动旋转摩擦焊接，以连接碳素钢（EN24）和镍基高温合金（IN718）的圆柱形试样，以及三个不同的焊接区-焊接界面（WI）/热机械影响区（TMAZ）的显微组织），热影响区（HAZ）和贱金属进行了检查。观察到该接头无缺陷，但形成了不均匀的飞边。电子背散射衍射（EBSD）分析显示TMAZ和HAZ中高角度晶界，低角度晶界和双晶界发生了实质性变化。此外，相对于贱金属，在WI / TMAZ观察到晶粒尺寸（2–5μm）显着细化。讨论了这些可能的原因。整个焊接接头的显微硬度分布显示出硬度变化。硬度的变化归因于晶粒细化，相变和强化沉淀物的溶解。拉伸试验结果表明，使用这种方法可以达到100％的联合效率。