Investigation and Implementation of a Robust Temperature Control Algorithm for Friction Stir Welding

摘要: Investigation and Implementation of a Robust Temperature Control Algorithm for Friction Stir Welding Kenneth Alec Ross Department Mechanical Engineering, BYU Master Science In friction stir welding, the temperature process zone affects properties resulting weld has dramatic effect on tool life in PCBN (polycrystalline cubic boron nitride) tools. Therefore an active control system that changes parameters to is desirable. Mayfield Sorensen proposed two-stage model contains inner loop controls spindle speed keep power constant outer setting desired based temperature. This work analysis implementation method their work. research shows input leads Due inertia associated with spindle, best achieved by commanding torque rather than speed. Heat transfer explored analytical models are developed. It shown response nonlinear. Nevertheless first-order approximation time delay sufficient select functional controller gains PID controller. Standard manual tuning techniques can be used achieve rise time, settling overshoot. Gains H-13 steel FSW were tuned produce approximately 7 seconds, 30 seconds overshoot 30%. Welds run using these various plate thicknesses, commanded temperatures, backing plates feed rates. all cases functioned properly was held standard deviation less one degree Celsius. Similar results presented welds