Incipient damage response of boron carbide from hypervelocity impact experiments

Hypervelocity rod impact experiments were conducted at the Dynamic Compression Sector in the Advanced Photon source to investigate the real-time failure response of boron carbide (t=3mm) to planar impact of copper rod projectiles (L= 3mm; diam.= 0.4mm). A set of compound refractive lenses (CRL) made out of beryllium were used to expand the beam and achieve a significantly larger field of view (FOV). An analysis looking into different CRL setups with 40 lenses, 80 lenses, and 120 lenses was done to examine the tradeoff between expanded FOV’s full width half maximum and signal intensity. A 6.1 mm FOV was achieved with good signal intensity. The expanded beam allowed the visualization of the front and back surface response at impact velocities ranging from 1.0 to 2.5 km/s. Image analysis tools were used for calibration, alignment, and to quantify the penetration velocities from the moment of impact. Depth of penetration, cavity volume, and the damage velocity were examined over the range of striking velocities studied. Calculation of peak stresses and stress waves on the ceramic material will be discussed in the study. The results of the above will be used to motivate new computational modeling efforts and model parameterization for both continuum and mesoscale simulations.