An improved numerical model of high-speed friction stir welding using a new tool-workpiece slip ratio

The interface slip state of high-speed friction stir welding (HSFSW) is challenging to determine, and accurate boundary conditions cannot be obtained. First, this paper studies the effects of velocity and temperature on the interface slip state, and establishes a new slip coefficient equation. Then, this equation was used to modify the velocity boundary conditions and improve the numerical calculation method of HSFSW. A numerical model of HSFSW was established and validated through experimental data. Finally, the effects of traverse speed and rotational speed on the temperature and void defects of HSFSW were elaborated, and the applicable process parameter range was determined. Specifically, void defects were observed at a rotational speed of 6000 rpm with traverse speeds of 1000 mm/min and 2000 mm/min, while surface peeling occurred at a traverse speed of 3000 mm/min with a rotational speed of 7000 rpm. This study establishes the optimal parameter range for aluminum alloy HSFSW, providing valuable guidance for future industrial applications.