Influence of strain rate on fracture mechanism of Mg-Gd-Y alloy

The influence of strain rate on the fracture mechanism of Mg-Gd-Y alloy was investigated. The quasi-static compression tests were conducted by using the servo-hydraulic testing machine. High strain rate experiments with 1 × 10³s^-1 and 1 × 10⁴s^-1 were performed on the split Hopkinson compression bar and ballistic impact, respectively. The results indicated that the brittle cleavage fracture was the main failure mode at a strain rate of 1 × 10^-3s^-1. At a strain rate of 1 × 10³ s^-1, hot-softening bands were observed and deformation localization was responsible for the fracture of alloy. With the increase of strain rate up to 1 × 10⁴s^-1, adiabatic shear band led to the failure of material in the stage of stable penetration. In addition, transformation bands were formed and therefore the increase of strain rate was benefit for the formation of transformation bands.