Spall failure of polycarbonate on nanosecond timescales

Polymers play an increasingly large role in application areas involving extreme loadings, however, there remain substantial gaps in our knowledge of polymer failure at very high strain rates, especially regarding spall failure. Further, the micromechanisms that control underlying void and crack growth are not fully understood. Here we present results on the spall failure of polycarbonate on nanosecond timescales measured using laser-driven micro-flyer (LDMF) plate impact and photonic Doppler velocimetry (PDV). Our experimental method additionally enables high-throughput testing, such that we can collect an order of magnitude more data points than traditional spall experiments. This large volume of tests allows us to generate spall strength statistics, analyze uncertainties, and robustly compare to microsecond timescale gas gun experiments. The results presented here will help guide our understanding of spall failure mechanisms as they relate to fundamental material time scales and deformation mechanisms.