Intermittent in-situ high-resolution X-ray microscopy of 400-nm porous glass under uniaxial compression: study of pore changes and crack formation
Résumé
The properties of porous glasses and their field of application strongly depend on the
characteristics of the void space. Understanding the relationship between their porous structure
and failure behaviour can contribute to the development of porous glasses with long-term
reliability optimized for specific applications. In the present work, we used X-ray computed
tomography with nanometric resolution (nano-CT) to image a controlled pore glass (CPG) with
400 nm-sized pores whilst undergoing uniaxial compression in-situ to emulate a stress process.
Our results show that in-situ nano-CT provides an ideal platform for identifying the
mechanisms of damage within glass with pores of 400 nm, as it allowed the tracking of the
pores and struts change of shape during compression until specimen failure. We have also
applied computational tools to quantify the microstructural changes within the CPG sample by
mapping the displacements and strain fields, and to numerically simulate the behaviour of the
CPG using a Fast Fourier Transform/phase-field method. Both experimental and numerical
data show local shear deformation, organized along bands, consistent with the appearance and
propagation of ± 45 degrees cracks.