IMPACT ENERGY RELEASE AND DAMAGE CHARACTERISTICS OF TWO HIGH-ENTROPY ALLOYS

In order to explore the impact energy release characteristics regularities of two typical high-entropy alloy materials, using the Φ14.5 mm ballistic gun launcher, the quasi-sealed test chamber system, two typical high-entropy alloy fragments, the FeNiMoW and the FeNiCoCr, were carried out the release energy effect tests at different impact velocities. Furthermore, the test platform was used to study the penetration and damage effect of two high-entropy alloy fragments to multi-layered targets, which were placed to the bottom of the test chamber. By changing the thickness of the steel target fixed in front of the test chamber, the impact release energy characteristics and damage regularities of two high-entropy alloy fragments to the subsequent multi-layered targets were studied. The study found that FeNiMoW and FeNiCoCr high-entropy alloy fragments began to react releasing chemical energy at around 1356 m/s and 1217 m/s, respectively. There was no chemical reaction reacted below this velocity. It was obvious that the impact velocities had a great influence to the release energy of the two high-entropy alloy fragments. As the velocity increased, the energy release response of the fragments became more intense, the peak overpressure showed a rising trend and the rising velocity became faster. As the thickness of the front steel target increased from 1 mm to 5 mm at an impact velocity of approximately 1600 m/s, it could be seen that the peak overpressures of FeNiMoW fragments showed a rise trend, and the peak overpressures of FeNiCoCr fragments showed a downward trend. In the process of the fragments perforating the front steel target and penetrating the multi-layered aluminum targets, the reduction of the release energy reaction degree will contribute to the enhancement of the penetration effect of the fragments, and the more increasing thickness of the front steel target will reduce the penetration and damage effect of the fragments to the multi-layered aluminum targets. On the other hand, as the thickness of the front steel target increases, the area of the first layer of aluminum target damaged by the fragments first increases and then decreases.