Determining the strength model parameters of an ultraviolet sensitive photopolymer

Plate impact experiments were conducted in Marquette University's 2 inch diameter bore light gas gun to study how an ultraviolet sensitive photopolymer responds to dynamic loading over various run distances. The targets and flyers were 3D printed with a Masked Stereolithography Apparatus (MSLA) resin printer and monitored via Photon Doppler Velocimetry (PDV) during plate impact experiments. Flyer velocities ranged from 150 m/s to 600 m/s. The targets were designed to have varying thickness levels for the shock wave to propagate through. The PDV probes monitored the free surface velocity of the target, each corresponding to a thickness of the target. The target thickness ranged from 0.25 mm, the minimal amount printable to 10mm, the maximum thickness of the target while maintaining uniaxial strain conditions due to the bore diameter of the gas gun. The result ensures a more complete understanding of the thermodynamic state of the materials during loading and unloading as a function of target thickness. The PDV tracers were also used as comparison results for the Multi Objective Genetic Algorithm in DAKOTA to determine a more accurate strength model and equation of state material parameters for modeling the ultraviolet sensitive photopolymer in hydrocodes such as CTH.