Mechanical and optical properties of vanadium under shock picosecond loads

Abstract

The evolution of compression pulses generated by a femtosecond laser in micron-thick vanadium film samples has been studied by the interferometric method with continuous recording of motion in the picosecond range. The relation of the velocity of a shock wave and the particle velocity behind its front indicates the elastic character of shock compression at pressures up to 46 GPa, for which the shear stress is 15.8 GPa. The measured spall strength reaches 21.8 GPa at a strain rate of ∼109 s−1. The picosecond dynamics of the reflection coefficient of vanadium, which indicates the excitation of its electronic subsystem under “cold” compression by an ultrashort shock wave, has been detected.