Process Developement of Integral Fasteners Using Friction Stir Spot Welding With “C-Frame” end Effector on an Aircraft Cabin Door Made From AA6061-T6 and AA2024-T3

Application of Friction Stir Spot welding (FSSW) to the creation of integral fasteners on an Aircraft Cabin Door using an industrial robot with a “C-Frame” end effector is explored. Plunge depth control, sheet lifting, pin temperature and anvil sticking issues are addressed. Tools with various shoulder concavities are investigated. Through optimization of forge load, spindle speed and process duration (dwell) time, integral fastener shear loads are found to be 1.8 times higher than resistance spot welding. Optimized anvil and spindle cooling time is found to be up to 9 seconds on the “C-Frame” end effector. Preliminary Welding Procedure Specification (pWPS) per AWSD 17.3 is developed. Frame and skin assembly articles are fastened together using three unique joining sequences. A “go — no go” inspection gage is used to verify pWPS standards. Hard tooling to shorten process time, robot cells and multiple end effector studies are proposed for further study.