Equation of state and strength of ruthenium aluminide

RuAl is a B2 intermetallic compound of technological interest for turbine blades and hypersonic applications, and is also a challenging prototype for constructing material models as virtually no shock or high pressure data are available. It stands out from many other alloys as the constituents have masses almost 4x different. We used density functional theory to predict the EOS of solid RuAl, and also the elastic moduli, Debye temperature, and melt curve. We compare the Hugoniot with an initial measurement at 737 GPa using magnetically accelerated flyers at the Z Pulsed Power Facility at Sandia National Laboratories. We used velocimetry in laser-driven shock experiments to measure the flow stress and spall strength. We also calibrated a damage model and a dislocation-based plasticity model suitable for high pressures, investigating the sensitivity to alternative choices to represent the dislocation mobility in a compound.