Phase transformation and mechanical properties of Ti50Ni50 alloy after high-velocity impact

To simulate the impact of space debris, Ti50Ni50 alloy is impacted at 1.2 km s−1 using a powder gun. Phase transformation, microstructure and mechanical properties in Ti50Ni50 alloy induced by impact are investigated. The results show that the phase transformation temperature shifts to a lower temperature in impacted Ti50Ni50 alloy. Variants lose their self-accommodated morphology, martensite plates widen, the variants interfaces migrate and bend under force, and many dislocations exist in the martensite plates. The microhardness reduces and the shape recovery ratio enhances gradually with the increase in distance from the crate. This is attributed to plastic deformation and working hardening caused by high-velocity impact.