Friction spot joining of TC4 alloy and ultra-high molecular weight polyethylene: Focused on temperature-force relationship

Abstract 3D printed porous TC4 alloy was joined with ultra-high molecular weight polyethylene (UHMWPE) via friction spot joining (FSpJ) in this study. The Z-axial load (Fz) and joining temperature (TJ) histories were measured with load cell beneath worktable and K-type thermocouple inserted in joints respectively. Strong joining strength (3000 N, fracture on polymer base material) was achieved after joining. The Fz evolution was calculated to be strongly correlated with polymer viscosity (η) during joining (dFz/dt ∝ η). Meanwhile, strong coupling effect between TJ and Fz (dTJ/dt ∝ Fz) was found. With optimized joining parameters, good macro−/micro- joining effect were achieved. These findings make it possible to predict joining quality and interface temperature during joining process via collecting Fz history.