Ju Li

Profile Information
Name
Ju Li
Institution
Massachusetts Institute of Technology
Position
Professor
h-Index
ORCID
0000-0002-7841-8058
Publications:
"Revealing hidden defects through stored energy measurements of radiation damage" Charles Hirst, Boopathy Kombaiah, Scott Middlemas, Ju Li, Michael Short, Science Advances Vol. 8 2022 eabn2733 Link
With full knowledge of a material’s atomistic structure, it is possible to predict any macroscopic property of interest. In practice, this is hindered by limitations of the chosen characterization techniques. For example, electron microscopy is unable to detect the smallest and most numerous defects in irradiated materials. Instead of spatial characterization, we propose to detect and quantify defects through their excess energy. Differential scanning calorimetry of irradiated Ti measures defect densities five times greater than those determined using transmission electron microscopy. Our experiments also reveal two energetically distinct processes where the established annealing model predicts one. Molecular dynamics simulations discover the defects responsible and inform a new mechanism for the recovery of irradiation-induced defects. The combination of annealing experiments and simulations can reveal defects hidden to other characterization techniques and has the potential to uncover new mechanisms behind the evolution of defects in materials.