Spatiotemporally resolved 5-MHz visualization and particle image velocimetry in early time multiphase blasts

•This study evaluates burst-mode laser-based particle-field visualization and time-resolved particle image velocimetry (TR-PIV) for planar measurements up to 5 MHz.•The cross-sectional flow structure, velocity, and acceleration of solid detonator blast products were quantified, including velocities of approximately 6 km/s.•A shape parameter is introduced to characterize the morphological evolution of the solid explosive products.•The spatiotemporal resolution enables the characterization of significant differences in velocity and acceleration between the orthogonal expansion directions.•A methodology to extend TR-PIV toward supplemental quantitative pressure measurements is introduced, and the pressure of the leading shock is quantified.