Plastic Waves of Combined Stresses Due to Longitudinal Impact of a Pretorqued Tube—Part 1: Experimental Results

Abstract

Experiments are reported in which annealed aluminum tubes are subjected to a static plastic torque followed by a longitudinal compressive impact. Measurements are made of both longitudinal and shear strain-time profiles at stations along the specimen. Qualitatively, the strain response at the gages corresponds to the arrival of a fast wave for which torsional strain decreases while longitudinal strain increases followed by a slow wave for which both torsional and longitudinal strains increase. Between the slow and fast waves and following the slow wave, a strain rate of the order of 10 sec−1 is maintained.