Shock-induced chemical reaction of Al/Ni composites subjected to hypervelocity impact: Experimental work and numerical simulation

This study aims to enhance the understanding of the energy release behavior and reaction characteristics of Al/Ni composites under hypervelocity impact. The Al/Ni composites with a molar ratio of 1:1 were prepared, and two-step impact initiation tests were carried out in a quasi-sealed test chamber at velocities ranging from 800 to 2800 m/s. The changes in pressure history inside the vented test chamber at different impact velocities and the energy released per unit mass of the material were analyzed. To further analyze the impact-initiated energy release characteristics of the Al/Ni composites, a coupled mechanics–thermotics–chemistry modeling method was developed based on the constitutive model and chemical reaction kinetics model. Then, the influence of impact velocity and target thickness on the energy release of Al/Ni composites was analyzed. The research results show that the energy released by impact reaction of Al/Ni composites with a molar ratio of 1:1 in the atmospheric has a limit, which is approximately 2.9 kJ/g. For steel and aluminum alloy plates, when the target plate thickness is relatively thin, changing the plate thickness and the impact velocity of the specimen will affect the energy release of the Al/Ni composites. However, when the plate thickness is increased to more than 2 mm, the thickness of the plate no longer affects the energy release of the Al/Ni composites, and only the impact velocity becomes a dominant factor.