Imperial College London
Alternate

ProfessorFinnGiuliani

Faculty of Engineering, Department of Materials

Professor in Structural Ceramics
 
 
 
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Contact

 

+44 (0)20 7594 1249f.giuliani

 
 
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Location

 

RSM LM04DRoyal School of MinesSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Waheed:2018:1361-651X/aa9ba2,
author = {Waheed, S and Hao, R and Zheng, Z and Wheeler, J and Michler, J and Balint, D and Giuliani, F},
doi = {1361-651X/aa9ba2},
journal = {Modelling and Simulation in Materials Science and Engineering},
title = {Temperature-dependent plastic hysteresis in highly confined polycrystalline Nb films},
url = {http://dx.doi.org/10.1088/1361-651X/aa9ba2},
volume = {26},
year = {2018}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - In this study, the effect of temperature on the cyclic deformation behaviour of a confined polycrystalline Nb film is investigated. Micropillars encapsulating a thin niobium interlayer are deformed under cyclic axial compression at different test temperatures. A distinct plastic hysteresis is observed for samples tested at elevated temperatures, whereas negligible plastic hysteresis is observed for samples tested at room temperature. These results are interpreted using planar discrete dislocation plasticity incorporating slip transmission across grain boundaries. The effect of temperature-dependent grain boundary energy and dislocation mobility on dislocation penetration and, consequently, the size of plastic hysteresis is simulated to correlate with the experimental results. It is found that the decrease in grain boundary energy barrier caused by the increase in temperature does not lead to any appreciable change in the cyclic response. However, dislocation mobility significantly affects the size of plastic hysteresis, with high mobilities leading to a larger hysteresis. Therefore, it is postulated that the experimental observations are predominantly caused by an increase in dislocation mobility as the temperature is increased above the critical temperature of body-centred cubic niobium.
AU  - Waheed,S
AU  - Hao,R
AU  - Zheng,Z
AU  - Wheeler,J
AU  - Michler,J
AU  - Balint,D
AU  - Giuliani,F
DO  - 1361-651X/aa9ba2
PY  - 2018///
SN  - 0965-0393
TI  - Temperature-dependent plastic hysteresis in highly confined polycrystalline Nb films
T2  - Modelling and Simulation in Materials Science and Engineering
UR  - http://dx.doi.org/10.1088/1361-651X/aa9ba2
UR  - http://hdl.handle.net/10044/1/53777
VL  - 26
ER  -
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