A Nanoindentation Study of the Plastic Deformation and Fracture Mechanisms in Single-Crystalline CaFe2As2
- Univ. of Connecticut, Storrs, CT (United States)
- Colorado State Univ., Fort Collins, CO (United States)
- Ames Lab. and Iowa State Univ., Ames, IA (United States)
In this paper, the plastic deformation and fracture mechanisms in single-crystalline CaFe2As2 has been studied using nanoindentation and density functional theory simulations. CaFe2As2 single crystals were grown in a Sn-flux, resulting in homogeneous and nearly defect-free crystals. Nanoindentation along the [001] direction produces strain bursts, radial cracking, and lateral cracking. Ideal cleavage simulations along the [001] and [100] directions using density functional theory calculations revealed that cleavage along the [001] direction requires a much lower stress than cleavage along the [100] direction. This strong anisotropy of cleavage strength implies that CaFe2As2 has an atomic-scale layered structure, which typically exhibits lateral cracking during nanoindentation. This special layered structure results from weak atomic bonding between the (001) Ca and Fe2As2 layers.
- Research Organization:
- Ames Laboratory (AMES), Ames, IA (United States)
- Sponsoring Organization:
- USDOE
- Grant/Contract Number:
- AC02-07CH11358
- OSTI ID:
- 1441005
- Report Number(s):
- IS-J--9667; PII: 2851
- Journal Information:
- JOM. Journal of the Minerals, Metals & Materials Society, Journal Name: JOM. Journal of the Minerals, Metals & Materials Society Journal Issue: 7 Vol. 70; ISSN 1047-4838
- Publisher:
- SpringerCopyright Statement
- Country of Publication:
- United States
- Language:
- English
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