Design and first tests of an electrically-driven exploding foil hypervelocity launcher for study of material behaviour at Mbar conditions

The conditions experienced by spacecrafts, lunar habitats and fusion reactors, to name a few examples, are unlike any found naturally on the earth's surface. The selection and design of resilient materials for such purposes therefore requires controlled access to these conditions, which in turn relies upon advancement of techniques to generate ever higher material pressures and temperatures. The electric gun projectile launcher is one such technique, which utilizes the rapid expansion of an ohmically heated exploding foil to accelerate thin flyers above 20 km/s. Though the launcher has the potential to access a largely unexplored thermodynamic space, the process of launching flyers above 0.25 mm thickness in this manner is highly variable, often resulting in uncontrolled launch characteristics and premature failure of the flyer. This behavior is challenging to diagnose experimentally, limiting the validation of numerical models and leaving uncertainties in material properties unresolved. This work presents the novel modelling, design, and experimental testing of the highest energy electric gun load in the world, powered by a 2.5 MJ capacitor bank. Preliminary results reveal the successful and repeatable launch of a 0.5 mm thick polymer flyer into a PMMA target block, generating impact pressures of 80 GPa. This advancement marks a stepping-stone towards optimizing the electric gun to achieve even higher pressures and shock durations, enabling it to probe a material phase space inaccessible to alternative projectile launchers.