Measurement of Strain Field Evolution in Real Time around Shockloaded Dynamically Collapsing Holes with X-ray Digital Image Correlation

Shock-loaded dynamic collapse of pores in solids has been a problem of interest because of its relevance to a variety of applications. Our previous experiment at the ESRF revealed the motion of the pore boundary in stunning detail, but was unable to track the kinematics in the material around the pore. In this work we propose to measure real-time evolution of strain field around shock-loaded collapsing holes on the mid-plane of the specimen with X-ray digital image correlation (XDIC). It involves introducing a micro speckle pattern on the specimen mid-plane around a through-hole and imaging its evolution during shock loading. The strain field is extracted through digital image correlation (DIC) of the micro speckle pattern. These experiments build on preliminary data we have collected at Advanced Photon Source (ID 35) recently. We plan to conduct experiments over a wide range of impact velocities that span the strength dominated regime to the hydrodynamic regime.