In Situ Scanning Transmission Electron Microscopy Observations of Fracture at the Atomic Scale

Lingli Huang, Fangyuan Zheng, Qingming Deng, Quoc Huy Thi, Lok Wing Wong, Yuan Cai, Ning Wang, Chun Sing Lee, Shu Ping Lau, Manish Chhowalla, Ju Li, Thuc Hue Ly, Jiong Zhao

Research output: Journal article publicationJournal articleAcademic researchpeer-review

4 Citations (Scopus)

Abstract

The formation, propagation, and structure of nanoscale cracks determine the failure mechanics of engineered materials. Herein, we have captured, with atomic resolution and in real time, unit cell-by-unit cell lattice-trapped cracking in two-dimensional (2D) rhenium disulfide (ReS2) using in situ aberration corrected scanning transmission electron microscopy (STEM). Our real time observations of atomic configurations and corresponding strain fields in propagating cracks directly reveal the atomistic fracture mechanisms. The entirely brittle fracture with non-blunted crack tips as well as perfect healing of cracks have been observed. The mode I fracture toughness of 2D ReS2 is measured. Our experiments have bridged the linear elastic deformation zone and the ultimate nm-sized nonlinear deformation zone inside the crack tip. The dynamics of fracture has been explained by the atomic lattice trapping model. The direct visualization on the strain field in the ongoing crack tips and the gained insights of discrete bond breaking or healing in cracks will facilitate deeper insights into how atoms are able to withstand exceptionally large strains at the crack tips.

Original languageEnglish
Article number246102
JournalPhysical Review Letters
Volume125
Issue number24
DOIs
Publication statusPublished - 9 Dec 2020

ASJC Scopus subject areas

  • Physics and Astronomy(all)

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