In situ x-ray diffraction of fast compressed iron: Analysis of strains and stress under non-hydrostatic pressure
IR@NAL: CSIR-National Aerospace Laboratories, Bangalore
View Archive Info| Field | Value | |
| Title |
In situ x-ray diffraction of fast compressed iron: Analysis of strains and stress under non-hydrostatic pressure
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| Creator |
Konopkova, Z
Rothkirch, A Singh, AK Speziale, S Liermann, HP |
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| Subject |
Chemistry and Materials (General)
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| Description |
Series of high-pressure x-ray diffraction patterns of iron and its high-pressure polymorphs were collected with
0.1ā0.2-s exposure time utilizing a membrane diamond anvil cell (DAC) for compression at various loading and
unloading rates to a maximum pressure of 70 GPa. Strain rates of 10ā2 sā1 at a maximum pressurization rate
of 4.1 GPa/s were achieved in non-hydrostatic compression of hcp Fe. Linewidth analysis was used to retrieve
strain and uniaxial stress of Fe as a function of pressure upon both compression and decompression. Analysis of
the lattice parameters ratio c/a of hcp Fe indicates the presence of complex non-hydrostatic stress states, which
developed as a function of strain rate, relaxation time, and various levels of hydrostaticity. Our results emphasize
the importance of a controlled pressurization in DACs because the experimental loading rate strongly influences
the stress state of the sample, particularly on decompression. Our time-resolved x-ray diffraction of the phase
transition from bcc Fe to hcp Fe reveals residual grains of bcc Fe capable of surviving to very high pressures
(>35 GPa) for a few minutes after the transition.
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| Publisher |
The American Physical Society
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| Date |
2015
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| Type |
Journal Article
PeerReviewed |
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| Format |
application/pdf
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| Identifier |
http://nal-ir.nal.res.in/12096/1/fast_compress.pdf
Konopkova, Z and Rothkirch, A and Singh, AK and Speziale, S and Liermann, HP (2015) In situ x-ray diffraction of fast compressed iron: Analysis of strains and stress under non-hydrostatic pressure. Physical Review B, 91 (14). pp. 144101-1. ISSN 1098-0121 |
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| Relation |
http://dx.doi.org/10.1103/PhysRevB.91.144101
http://nal-ir.nal.res.in/12096/ |
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