The successful process of amalgamating both the time-resolved imaging capabilities present at the Advanced Photon Source beamline 32ID-B and the proficiency of high-rate loading offered by the split Hopkinson or Kolsky compression/tension bar apparatus is discussed and verification of system effectiveness is expressed via dynamic experiments on various material systems. Single particle sand interaction along with glass cracking during dynamic compression, and fiber-epoxy interfacial failure, ligament-bone debonding, and single-crystal silicon fragmentation due to dynamic tension, were imaged with 0.5 μs temporal resolution and μm-level spatial resolution. Synchrotron x-ray phase contrast imaging of said material systems being loaded with the Kolsky bar apparatus demonstratively depicts the effectiveness of the novel union between these two powerful techniques, thereby allowing for in situ analysis of the interior of the material system during high-rate loading for a variety of applications.

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Failure mechanisms in individual sand particles under compressive loading at different loading rates were investigated using X-ray imaging. High speed X-ray phase contrast imaging was utilized to study the damage mechanisms in dry and wet sand under dynamic compressive loading. A modifi ed Kolsky bar setup was used to apply controlled dynamic compression on two contacting sand particles. One of the particles was observed to pulverize, whereas other particle remained intact for dry sand particles with average failure load of 34.344 N. In wet conditions, one of the particles was observed to break into large subparticles which pulverized upon further loading. Other particle was observed to stay intact. The failure load was observed to increase to 65.466 N for wet particles. 3D X-ray tomography was used to assess the failure of dry sand particles under static compressive loading. One particle broke into large subparticles which subsequently pulverized under static compressive loading. Even under static loading, second particle did not fail until fi rst particle was completely pulverized. The pulverization load under static compressive loading was observed to be 42 N. The order of pulverization for the particles was observed to be random in all experiments.

Split Hopkinson or Kolsky bars are common high-rate characterization tools for dynamic mechanical behaviour of materials. Stress–strain responses averaged over specimen volume are obtained as a function of strain rate. Specimen deformation histories can be monitored by high-speed imaging on the surface. It has not been possible to track the damage initiation and evolution during the dynamic deformation inside specimens except for a few transparent materials. In this study, we integrated Hopkinson compression/tension bars with high-speed X-ray imaging capabilities. The damage history in a dynamically deforming specimen was monitored in situ using synchrotron radiation via X-ray phase contrast imaging. The effectiveness of the novel union between these two powerful techniques, which opens a new angle for data acquisition in dynamic experiments, is demonstrated by a series of dynamic experiments on a variety of material systems, including particle interaction in granular materials, glass impact cracking, single crystal silicon tensile failure and ligament–bone junction damage.

High‐speed X‐ray phase contrast imaging synchronized with a Kolsky bar apparatus was utilized to investigate the cracking behavior of a borosilicate glass, a soda lime glass, and a glass ceramic in front of a cylindrical projectile with an impact velocity of 5 ms−1. For each material, three different surface conditions were prepared for the impacted edge of the specimen. Angular cracking was observed in front of the projectile for borosilicate glass. For soda lime glass, straight cracking was observed. For glass ceramic, curved cracking was observed in front of the projectile. Cracking behavior was observed to be independent of the surface condition on the impacted edge.