Multiscale XCT Scans to Study Damage Mechanism in Syntactic Foam

Abstract

In this work, we applied the in-situ X-ray Computed Tomography (XCT) mechanical testing method that coupled the in-situ mechanical loading with the XCT imaging to study the damage mechanism of GMBs inside the Sylgard as the material was subject to mechanical loading. We studied Sylgard specimens with different volume fraction of GMBs to understand how they behave differently under compression loading and how the volume fraction of GMBs affect the Sylgard failure.

Both high resolution (1.5 μm/voxel) and low resolution (10 μm/voxel) XCT imaging were performed at different loading levels to visualize the GMB collapse during the compression of Sylgard with different volume fraction of GMBs. Feret shape of GMBs were calculated from the high resolution XCT images to determine whether the GMBs were intact or fractured, as well as the relationship between the size distribution of GMBs and their Feret shapes. Through these quantitative analysis of the high resolution XCT data, we were able to understand how the size and volume fraction of GMBs affect their failure behavior. The Digital volume correlation (DVC) technique was applied to the low resolution XCT images to calculate the local deformation of Sylgard specimen, which enabled us to understand the different failure propagation and failure mechanisms of Sylgard with different volume fraction of GMBs.