Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-05T04:46:43.675Z Has data issue: false hasContentIssue false

Room-temperature creep of nanoporous silica

Published online by Cambridge University Press:  24 January 2011

S.O. Kucheyev*
Affiliation:
Lawrence Livermore National Laboratory, Livermore, California 94551
K.A. Lord
Affiliation:
Lawrence Livermore National Laboratory, Livermore, California 94551
A.V. Hamza
Affiliation:
Lawrence Livermore National Laboratory, Livermore, California 94551
*
a)Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

We show that low-density nanoporous silica monoliths (aerogels), in contrast to the case of full-density silica, exhibit pronounced time-dependent deformation during indentation at room temperature. Logarithmic indentation creep and stress relaxation are revealed, with an exponential dependency of the creep constant on the applied stress. Such time-dependent deformation is attributed to stress corrosion fracture of nanoligaments that have a large surface-to-bulk atomic fraction.

Type
Articles
Copyright
Copyright © Materials Research Society 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1.Pekala, R.W., Alviso, C.T., and LeMay, J.D.: Organic aerogels: Microstructural dependence of mechanical-properties in compression. J. Non-Cryst. Solids 125, 67 (1990).CrossRefGoogle Scholar
2.Gross, J., Fricke, J., Pekala, R., and Hrubesh, L.W.: Elastic nonlinearity of aerogels. Phys. Rev. B 45, 12774 (1992).Google Scholar
3.Woignier, T., Reynes, J., Alaoui, A.H., Beurroies, I., and Phalippou, J.: Different kinds of structure in aerogels: Relationships with the mechanical properties. J. Non-Cryst. Solids 241, 45 (1998).Google Scholar
4.Moner-Girona, M., Roig, A., Molins, E., Martinez, E., and Esteve, J.: Micromechanical properties of silica aerogels. Appl. Phys. Lett. 75, 653 (1999).Google Scholar
5.Lucas, E.M., Doescher, M.S., Ebenstein, D.M., Wahl, K.J., and Rolison, D.R.: Silica aerogels with enhanced durability, 30-nm mean pore-size, and improved immersibility in liquids. J. Non-Cryst. Solids 350, 244 (2004).Google Scholar
6.Kucheyev, S.O., Baumann, T.F., Cox, C.A., Wang, Y.M., Satcher, J.H. Jr., and Hamza, A.V.: Nanoengineering mechanically robust aerogels via control of foam morphology. Appl. Phys. Lett. 89, 041911 (2006).CrossRefGoogle Scholar
7.Fan, H., Hartshorn, C., Buchheit, T., Tallant, D., Assink, R., Simpson, R., Kissel, D.J., Lacks, D.J., Torquato, S., and Brinker, C.J.: Modulus-density scaling behavior and framework architecture of nanoporous self-assembled silicas. Nat. Mater. 6, 418 (2007).CrossRefGoogle ScholarPubMed
8.Leonard, A., Blacher, S., Crine, M., and Jomaa, W.: Evolution of mechanical properties and final textural properties of resorcinol-formaldehyde xerogels during ambient air drying. J. Non-Cryst. Solids 354, 831 (2008).Google Scholar
9.Worsley, M.A., Kucheyev, S.O., Satcher, J.H. Jr., Hamza, A.V., and Baumann, T.F.: Mechanically robust and electrically conductive carbon nanotube foams. Appl. Phys. Lett. 94, 073115 (2009).Google Scholar
10.Kucheyev, S.O., Hamza, A.V., Satcher, J.H. Jr., and Worsley, M.A.: Depth-sensing indentation of low-density brittle nanoporous solids. Acta Mater. 57, 3472 (2009).Google Scholar
11.Angell, C.A.: Perspective on the glass-transition. J. Phys. Chem. Solids 49, 863 (1988).CrossRefGoogle Scholar
12.Kucheyev, S.O., Toth, M., Baumann, T.F., Hamza, A.V., Ilavsky, J., Knowles, W.R., Saw, C.K., Thiel, B.L., Tileli, V., van Buuren, T., Wang, Y.M., and Willey, T.M.: Structure of low-density nanoporous dielectrics revealed by low-vacuum electron microscopy and small-angle x-ray scattering. Langmuir 23, 353 (2007).Google Scholar
13.Oliver, W.C. and Pharr, G.M.: An improved technique for determining hardness and elastic-modulus using load and displacement sensing indentation experiments. J. Mater. Res. 7, 1564 (1992).Google Scholar
14.Abramoff, B. and Klein, L.C.: Elastic properties of silica xerogels. J. Am. Ceram. Soc. 73, 3466 (1990).Google Scholar
15.Daughton, D.R., MacDonald, J., and Mulders, N.: Acoustic properties of silica aerogels between 400 mK and 400 K. J. Non-Cryst. Solids 319, 297 (2003).CrossRefGoogle Scholar
16.Basu, S., Radovic, M., and Barsoum, M.W.: Room temperature constant-stress creep of a brittle solid studied by spherical nanoindentation. J. Appl. Phys. 104, 063522 (2008).Google Scholar
17.Orowan, E.: The fatigue of glass under stress. Nature 154, 341 (1944).CrossRefGoogle Scholar
18.Lawn, B.R.: Fracture of Brittle Solids (Cambridge University Press, Cambridge, MA, 1998).Google Scholar
19.Michalske, T.A. and Freiman, S.W.: A molecular interpretation of stress-corrosion in silica. Nature 295, 511 (1982).Google Scholar
20.Michalske, T.A. and Bunker, B.C.: Slow fracture model based on strained silicate structures. J. Appl. Phys. 56, 2686 (1984).CrossRefGoogle Scholar
21.Kucheyev, S.O., Worsley, M.A., Satcher, J.H. Jr., Hamza, A.V., and Baumann, T.F.(2009).Google Scholar