Study on energy release characteristics and penetration effects to concrete targets of Hf-based amorphous alloys

•The critical velocity for the energy release of Hf-based amorphous alloy is about 625 m/s.•The impact velocity shows a positive correlation with the overpressure, the energy release and time effect of energy release characteristics.•The energy release reaction of Hf-based amorphous alloy significantly enhanced the penetration effect of the projectiles into concrete targets by increasing the penetration depth and the crater. In this paper, the energy release characteristics and penetration effects of Hf-based amorphous alloys subjected to high velocity impact were investigated. The quasi-sealed test chamber system was used to record the impact energy release process of Hf-based amorphous alloy fragments shotted by 14.5 mm ballistic gun at elevated impact velocities. The reaction behaviors were observed by the high-speed camera and measured by the history curves of the impact reaction pressure using a piezoresistive pressure sensor. The penetration experiments of jacketed long rod projectiles (LRPs) of Hf-based amorphous alloys launching into concrete targets were carried out by 30 mm ballistic gun with velocities about 1400 m/s, where the experiments with inert steel jacketed LRPs were taken as a contrast. The video frames from the impact events were recorded by the high-speed camera. The results demonstrated that obviously shock-induced chemical reactions took place in Hf-based amorphous alloy fragments during the impact process, where the impact velocity played a significant role. Compared with the traditional steel jacketed LRPs, both the penetration depth and the crater of Hf-based amorphous alloy jacketed LRPs to concrete targets were significantly increased, which indicated that Hf-based amorphous alloy could be used to increase the damage effects of warheads.