On the ballistic impact resistance of additive manufactured managing steel targets compared to that of cast targets

The advent of additive manufacturing (AM) in the defence industry has introduced possibilities for customisable and optimised light-weight armour. Maraging steel is well suited to AM and takes on ultra high-strength post heat-treatment, lending it significant potential for protective applications. Promising ballistic performance has been demonstrated in the literature albeit with a tendency for brittle behaviour; it remains unknown to what extent the AM process is responsible for the unfavourable strength versus ductility trade off. Here, AM maraging steel in both the as-printed and heat-treated state has been experimentally characterised, examined, and tested in a ballistic range alongside its traditionally cast counterpart. Very little difference was found in the ballistic limit velocity of the AM maraging steel compared to cast both before and after heat treatment, despite a dramatic reduction in ductility. In the majority of the ballistic impact tests, damage inflicted on the projectile core was more extensive for the AM targets than for the cast.