Large local deflections of a dynamic crack front induced by intrinsic dislocations in brittle single crystals

D Shilo; D Sherman; I Beery; E Zolotoyabko

doi:10.1103/PhysRevLett.89.235504

Large local deflections of a dynamic crack front induced by intrinsic dislocations in brittle single crystals

Phys Rev Lett. 2002 Dec 2;89(23):235504. doi: 10.1103/PhysRevLett.89.235504. Epub 2002 Nov 18.

Authors

D Shilo¹, D Sherman, I Beery, E Zolotoyabko

Affiliation

¹ Department of Materials Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.

PMID: 12485019
DOI: 10.1103/PhysRevLett.89.235504

Abstract

We show that intrinsic dislocations in brittle single crystals can be a source of strong local perturbations along the crack path. A theoretical model was developed which predicts substantial crack front deflections. Investigating the crack surfaces in Si crystals with induced dislocation density of 10(9)-10(10) cm(-2) revealed a significant amount of crack front perturbations in the form of V-shaped grooves, which were completely missing in dislocation-free Si specimens. The measured depths of the perturbations were in the range of 2-20 nm and in excellent agreement with the theoretical model.