Influence of impurities on the α to ω phase transition in zirconium under dynamic loading conditions

Abstract

Experiments have been carried out to investigate the α to ω phase transition in polycrystalline zirconium (Zr) metal. Samples with three levels of impurities were shock loaded using both gas-driven and powder-driven guns and ramp loaded using magnetic drive to investigate the effects of impurities on the properties of this solid-solid phase transition. Samples were backed by either sapphire or LiF windows and data were obtained using a VISAR to record the particle velocity at the sample/window interface. The results of these experiments showed significant differences in both the transition stress and kinetics for samples with different impurity levels demonstrating that impurities play an important role in the transformation mechanism in zirconium.