Imperial College London
Alternate

ProfessorFionnDunne

Faculty of Engineering, Department of Materials

Principal Research Fellow
 
 
 
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Contact

 

+44 (0)20 7594 2884fionn.dunne

 
 
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Location

 

104Royal School of MinesSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Jun:2016:10.1016/j.actamat.2016.01.057,
author = {Jun, T and Zhang, Z and Sernicola, G and Dunne, F and BRITTON, TB},
doi = {10.1016/j.actamat.2016.01.057},
journal = {Acta Materialia},
pages = {298--309},
title = {Local strain rate sensitivity of single α phase within a dual-phase Ti alloy},
url = {http://dx.doi.org/10.1016/j.actamat.2016.01.057},
volume = {107},
year = {2016}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - We have performed in-situ micropillar compression to investigate the local strain rate sensitivity of single α phase in dual-phase Ti alloy, Ti-6Al-2Sn-4Zr-2Mo (wt%). Electron backscatter diffraction (EBSD) was used to identify two grains, anticipated to primarily activate ⟨a⟩ slip on the basal and prismatic plane respectively. Comparative micropillars were fabricated within single α laths and load-hold tests were conducted with variable strain rates (on the order of 10-2 to 10-4s-1). Local strain rate sensitivity exponent (i.e. m value) is determined using two types of methods, constant strain rate method (CSRM) and conventional stress relaxation method (SRM), showing similar rate sensitivity trends but one order higher magnitude in SRM. We thus propose a new approach to analyse the SRM data, resulting in satisfactory agreement with the CSRM. Significant slip system dependent rate sensitivity is observed such that the prism slip has a strikingly higher m value than the basal. Fundamental mechanisms differing the rate sensitivity are discussed with regards to dislocation plasticity, where more resistance to move dislocations and hence higher hardening gradients are found in the basal slip. The impact of this finding for dwell fatigue deformation modes and the effectiveness of the present methodology for screening new alloy designs are discussed.
AU  - Jun,T
AU  - Zhang,Z
AU  - Sernicola,G
AU  - Dunne,F
AU  - BRITTON,TB
DO  - 10.1016/j.actamat.2016.01.057
EP  - 309
PY  - 2016///
SN  - 1359-6454
SP  - 298
TI  - Local strain rate sensitivity of single α phase within a dual-phase Ti alloy
T2  - Acta Materialia
UR  - http://dx.doi.org/10.1016/j.actamat.2016.01.057
UR  - https://www.sciencedirect.com/science/article/pii/S1359645416300544
UR  - http://hdl.handle.net/10044/1/29031
VL  - 107
ER  -
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