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Measuring Local Mechanical Properties using FIB Machined Cantilevers

Published online by Cambridge University Press:  31 January 2011

David Edward John Armstrong
Affiliation:
[email protected], University of Oxford, Department of Materials, Oxford, United Kingdom
Angus Jonathan Wilkinson
Affiliation:
[email protected], University of Oxford, Department of Materials, Oxford, United Kingdom
Steve George Roberts
Affiliation:
[email protected], University of Oxford, Department of Materials, Oxford, United Kingdom
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Abstract

Micro-scale Focused Ion Beam (FIB) machined cantilevers were manufactured in single crystal copper, polycrystalline copper and a copper-bismuth alloy. These were imaged and tested in bending using a nanoindenter. Cantilevers machined inside a single grain of polycrystalline copper were tested to determine their (anisotropic) Young's modulus: results were in good agreement with values calculated from literature values for single crystal elastic constants. The size dependence of yield behavior in the Cu microcantilevers was also investigated. As the thickness of the specimen was reduced from 23μm to 1.7μm the yield stress increased from 300MPa to 900MPa. Microcantilevers in Cu-0.02%Bi were manufactured containing a single grain boundary of known character, with a FIB-machined sharp notch on the grain boundary. The cantilevers were loaded to fracture allowing the fracture toughness of grain boundaries of different misorientations to be determined.

Type
Research Article
Copyright
Copyright © Materials Research Society 2009

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References

1. Maio, D. Di and Roberts, S.G., Measuring fracture toughness of coatings using focusedion-beam-machined microbeams, Journal of Materials Research, 20(2): p. 299302. 2005.10.1557/JMR.2005.0048Google Scholar
2. Kiener, D., Grosinger, W., Dehm, G., and Pippan, R., A further step towards an understanding of size-dependent crystal plasticity: In situ tension experiments of miniaturized single-crystal copper samples, Acta Materialia, 56(3): p. 580592. 2008.10.1016/j.actamat.2007.10.015Google Scholar
3. Uchic, M.D. and Dimiduk, D.A., A methodology to investigate size scale effects in crystalline plasticity using uniaxial compression testing, Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing, 400: p. 268278 .2005.10.1016/j.msea.2005.03.082Google Scholar
4. Halliday, F.M., Armstrong, D.E.J., Murphy, J.D., and Roberts, S.G., Nanoindentation and micromechanical testing of iron-chromium alloys implanted with iron ions, Adavnced Materials Research, 59: p. 304307. 2009.10.4028/www.scientific.net/AMR.59.304Google Scholar
5. Armstrong, D.E.J., Wilkinson, A.J., and Roberts, S.G., Measuring Anisotropy in Young’s Modulus of Copper Using Microcantilever Testing, Journal of Materials Research (submitted). 2009.10.1557/jmr.2009.0396Google Scholar
6. Sigle, W., Chang, L.S., and Gust, W., On the correlation between grain-boundary segregation, faceting and embrittlement in Bi-doped Cu, Philosophical Magazine a-Physics of Condensed Matter Structure Defects and Mechanical Properties, 82(8): p. 15951608. 2002.Google Scholar
7. Keast, V.J., Fontaine, A. La, and Plessis, J. du, Variability in the segregation of bismuth between grain boundaries in copper, Acta Materialia, 55(15): p. 51495155. 2007.10.1016/j.actamat.2007.05.034Google Scholar
8. Ledbetter, H. and Naimon, E.R., Elastic Properties of Metals and Alloys. II. Copper, Journal of physical and chemical reference data, 3: p. 897. 1974.10.1063/1.3253150Google Scholar
9. Kiener, D., Motz, C., Schoberl, T., Jenko, M., and Dehm, G., Determination of mechanical properties of copper at the micron scale, Advanced Engineering Materials, 8(11): p. 11191125. 2006.10.1002/adem.200600129Google Scholar
10. Wang, J.S. and Anderson, P.M., Fracture-Behavior of Embrittled Fcc Metal Bicrystals, Acta Metallurgica Et Materialia, 39(5): p. 779792. 1991.10.1016/0956-7151(91)90278-9Google Scholar
11. Armstrong, D.E.J., Rogers, M., and Roberts, S.G., Micromechanical Testing of Stress Corrosion Cracking of Individual Grain Boundaries, Journal of Materials Research (submitted). 2009.Google Scholar