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{Zhang:2018:10.1016/j.ijfatigue.2018.03.030,
author = {Zhang, Z and FPE, D},
doi = {10.1016/j.ijfatigue.2018.03.030},
journal = {International Journal of Fatigue},
pages = {324--334},
title = {Phase morphology, variants and crystallography of alloy microstructures in cold dwell fatigue},
url = {http://dx.doi.org/10.1016/j.ijfatigue.2018.03.030},
volume = {113},
year = {2018}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - This paper examines microscale crystal slip accumulation, cold creep, and stress redistribution (load shedding) related to dwell fatigue in a range of α–β Ti alloy microstructures. The role of basal slip and prism slip is evaluated in load shedding in a rogue grain combination. The results enrich the Stroh dislocation pile up interpretation of dwell by accounting for the anisotropic rate dependence of differing slip systems together with morphology.Microstructural morphology has been found to play an essential role in cold creep and load shedding in dwell fatigue. Basketweave structures with multiple α variants have been shown to give the lowest load shedding for which the mechanistic explanation is that the β lath structures provide multiple, small-scale α variants which inhibit creep and hence stress relaxation, thus producing more uniform, diffuse stress distributions across the microstructure through microscale kinematic confinement, imposed by multi (α)-to-single (β) BOR relations (i.e. multiple α variants sharing the same parent β grain). The critical consequence of this is that alloys typically having multi-variant basketweave structure (e.g. Ti-6246), remain free of dwell fatigue debit whereas those alloys associated with globular colony structures (e.g. Ti-6242) suffer significant dwell debit. This understanding is important in microstructural design of titanium alloys for resisting cold dwell fatigue.
AU  - Zhang,Z
AU  - FPE,D
DO  - 10.1016/j.ijfatigue.2018.03.030
EP  - 334
PY  - 2018///
SN  - 0142-1123
SP  - 324
TI  - Phase morphology, variants and crystallography of alloy microstructures in cold dwell fatigue
T2  - International Journal of Fatigue
UR  - http://dx.doi.org/10.1016/j.ijfatigue.2018.03.030
UR  - http://hdl.handle.net/10044/1/58548
VL  - 113
ER  -
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