Measurement of Coefficient of Dynamic Friction between Stir Rod and Material in Friction Stir Welding

In the present study, unsteady-state friction heating experiments and corresponding numerical analysis applying spreadsheet of Excel have been conducted for the purpose of evaluating the coefficient of dynamic friction between a stir rod and an aluminum alloy A7075, which is indispensable for elucidating heat transfer process in friction stir welding, spot friction stir welding and so on. It has been shown that, from the matching between the measured and calculated results on the back side temperature change of the specimen center with time, the first approximate value of 0.25 can be evaluated for the coefficient of dynamic friction between the stir rod and A7075, which has not been clarified so far.