Hostname: page-component-76fb5796d-skm99 Total loading time: 0 Render date: 2024-04-26T05:57:27.962Z Has data issue: false hasContentIssue false
  • English
  • Français

Torsion and bending of micron-scaled structures

Published online by Cambridge University Press:  31 January 2011

A. C. M. Chong ,
F. Yang ,
D. C. C. Lam  and
P. Tong
A. C. M. Chong*
Affiliation:
Department of Mechanical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, People's Republic of China
F. Yang
Affiliation:
Institute of Computational Engineering and Science, Southwest Jiaotong University, Chengdu 610031, Sichuan, People's Republic of China and Department of Mechanical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, People's Republic of China
D. C. C. Lam
Affiliation:
Department of Mechanical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, People's Republic of China
P. Tong
Affiliation:
Department of Mechanical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, People's Republic of China
*
a)Address all correspondence to this author.mearthur@ust.hk
Get access

Abstract

Typical microelectromechanical systems (MEMS) devices and packages are composed of micron-scaled structures. Experimental investigations on the effect of size on the deformation behavior of simple structures have shown that the deformation behavior of metals and polymers is size dependent. The size dependence in small structures is attributed to the contribution of nonnegligible strain gradients. In this work, torsion and bending of micron-sized rods and plates were analyzed by using a two-parameter model of strain-gradient plasticity. Microrod torsion and microplate bending experimental data were analyzed to determine the magnitude of the strain-gradient material parameters. The parametric analyses showed that conventional analysis is applicable only when the size of the structure is significantly larger than the material parameters, which are typically in the micron range. Strain-gradient analysis of micron-sized rod revealed that the presence of strain gradient increased the torque by three to nine times at the same twist. For MEMS structures with micron-sized features, conventional structural analysis without strain gradient is potentially inadequate, and strain-gradient analysis must be conducted to determine the elastoplastic behavior in the micron scale.

Type
Articles
Information
Journal of Materials Research , Volume 16 , Issue 4 , April 2001 , pp. 1052 - 1058
Copyright
Copyright © Materials Research Society 2001

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.Fleck, N.A., Muller, G.M., Ashby, M.F., and Hutchinson, J.W., Acta Metall. Mater. 42, 475 (1994).CrossRefGoogle Scholar
2.Iken, J.S.St. and Evans, A.G., Acta Mater. 46, 5109 (1998).Google Scholar
3.Nix, W.D. and Gao, H., J. Mech. Phys. Solids 46, 411 (1998).CrossRefGoogle Scholar
4.Stelmashenko, N.A., Walls, M.G., Brown, L.M., and Milman, Y.V., Acta Metall. Mater. 41, 2855 (1993).CrossRefGoogle Scholar
5.Ma, Q. and Clarke, D.R., J. Mater. Res. 10, 853 (1995).CrossRefGoogle Scholar
6.Poole, W.J., Ashby, M.F., and Fleck, N.A., Scripta Mater. 34, 599 (1996).CrossRefGoogle Scholar
7.Lam, D.C.C and Chong, A.C.M., J. Mater. Res. 14, 3784 (1999).CrossRefGoogle Scholar
8.Chong, A.C.M. and Lam, D.C.C., J. Mater. Res. 14, 4103 (1999).CrossRefGoogle Scholar
9.Toupin, R.A., Arch. Ration. Mech. Anal. 11, 385 (1962).CrossRefGoogle Scholar
10.Mindlin, R.D. and Tiersten, H.F., Arch. Ration. Mech. Anal. 11, 415 (1962).Google Scholar
11.Koiter, W.T., Proc. Ned. Akad. Wet. (B) 67, 17 (1964).Google Scholar
12.Mindlin, R.D., Arch. Ration. Mech. Anal. 16, 51 (1964).CrossRefGoogle Scholar
13.Fleck, N.A. and Hutchinson, J.W., J. Mech. Phys. Solids 41, 1825 (1993).CrossRefGoogle Scholar
14.Fleck, N.A. and Hutchinson, J.W., Adv. Appl. Mech. 33, 295 (1997).CrossRefGoogle Scholar
15.Mindlin, R.D., Int. J. Solids Struct. 1, 417 (1965).CrossRefGoogle Scholar
16.Smyshlyaev, V.P. and Fleck, N.A., J. Mech. Phys. Solids 44, 465 (1996).CrossRefGoogle Scholar
17.Hwang, K.C. and Inone, T., Mat. Sci. Res. Int. 4, 227 (1998).Google Scholar
18.Yang, F., Chong, A.C.M., Lam, D.C.C., and Tong, P. (to be submitted) (2000).Google Scholar
19.Gao, H., Huang, Y., Nix, W.D., and Hutchinson, J.W., J. Mech. Phys. Solids 47, 1239 (1999).CrossRefGoogle Scholar