Stable crack propagation in dislocation-engineered oxide visualized by double cleavage drilled compression test
Abstract
Understanding crack tip - dislocation interaction is critical for improving the fracture resistance of semi-brittle materials like room-temperature plastically deformable ceramics. Here, we use a modified double cleavage drilled compression (DCDC) specimen geometry, which facilitates stable crack propagation, to achieve in situ observation of crack tip - dislocation interaction. MgO specimens, furnished with dislocation-rich barriers, were employed to study how dislocations influence crack propagation. Crack progression was clearly observed to decelerate within dislocation-rich regions, slowing to 15% of its velocity as compared to the pristine crystal. Upon exiting these regions, cracks reaccelerated until reaching the next dislocation-rich barrier. Coupled phase field and crystal plasticity modeling replicates the experimental observations and provides mechanistic insight into crack tip - dislocation interactions. The aligned experiment and simulation results underscore the robustness of the technique and its potential to inform the design of more fracture-resistant ceramics via dislocations.
Cite
@article{arxiv.2508.11965,
title = {Stable crack propagation in dislocation-engineered oxide visualized by double cleavage drilled compression test},
author = {Oliver Preuß and Zhangtao Li and Enrico Bruder and Philippe Carrez and Yinan Cui and Jürgen Rödel and Xufei Fang},
journal= {arXiv preprint arXiv:2508.11965},
year = {2025}
}