Mechanical and energy release properties of cold-sprayed nickel-aluminum energetic structural materials

Nickel-aluminum energetic structural materials (Ni–Al ESMs) are widely applied in the defense industry due to their excellent mechanical and energy release properties. By utilizing an inert atmosphere at low temperatures, cold-spray effectively suppresses premature reactions in Ni–Al ESMs. Current studies on cold-spray ESMs have primarily relied on nickel-aluminum mixed powders. There is a need for further research to understand how different Ni–Al powder microstructures affect the mechanical and energy release properties of cold-spray ESMs. This study prepared ESM specimens with nickel-coated aluminum (Ni@Al) and Ni–Al powders through cold spraying. The microstructural features of the specimens were analyzed via optical microscopy. The mechanical properties of Ni@Al esm were investigated through quasi-static and dynamic compression tests. Results show that Ni@Al esm exhibits higher compressive strength and lower fracture strain, which can be attributed to its distinct microstructure. Impact tests were also conducted on the specimens to study their energy release characteristics. The results indicated that due to microstructural differences, Ni@Al ESMs were more prone to Al oxidation under high-speed impact, granting them stronger energy release abilities than Ni–Al ESMs.