EFFECT OF THERMAL-SOFTENING IN ROD IMPACT TEST FOR THE DETERMINATION OF DYNAMIC MATERIAL PROPERTIES OF POLYCARBONATE

A theory was developed to investigate the effect of thermal-softening in rod impact test for the determination of the dynamic material prope rties of Polycarbonate, on the basis of one-dimensional shock wave pro pagation phenomena. High velocity rod impact test was performed with f lat-ended cylindrical rod specimens. From the geometrical measurements of deformed rod, dynamic material properties were determined by both previous theories and the theory suggested in this work. The variation of temperature rise due to adiabatic plastic deformation with impact velocities and the effect of thermal-softening on the dynamic yield st ress were analyzed.