Effects of temperature on the flow stress of aluminum in shock waves and rarefaction waves

Elastic-plastic waves of shock compression and unloading in annealed AD1 aluminum were recorded at room temperature, 508 degrees C, and 610 degrees C. Using measurements of the parameters of the plastic shock waves and quasi-elastic rarefaction waves at the peak shock stresses from about 1.5 to 4.2 GPa, the strain rate dependences on the stress, the temperatures, and the loading histories were obtained in the range of 10(5)-10(7) s(-1). The initial resistance to high-rate deformation was found to increase anomalously with increasing temperature, but even a small deformation in the shock wave and the accompanying multiplication of dislocations changed the sign of the temperature dependence of the flow stress. Published under license by AIP Publishing.