Hostname: page-component-848d4c4894-x5gtn Total loading time: 0 Render date: 2024-05-02T05:26:01.649Z Has data issue: false hasContentIssue false

Determination of Residual-Stress-Free State and Mapping of Residual Stress Fields Using Speckle Interferometry and Thermal Relaxation

Published online by Cambridge University Press:  01 February 2011

Dong-Won Kim
Affiliation:
National Research Lab. for NanoAssessment & MicroReliability, School of Materials Science and Engineering, Seoul National University, San 56–1, Shilim-dong, Kwanak-Gu, 151–742, Seoul, Korea.
Jong-jin Kim
Affiliation:
National Research Lab. for NanoAssessment & MicroReliability, School of Materials Science and Engineering, Seoul National University, San 56–1, Shilim-dong, Kwanak-Gu, 151–742, Seoul, Korea.
Dongil Son
Affiliation:
National Research Lab. for NanoAssessment & MicroReliability, School of Materials Science and Engineering, Seoul National University, San 56–1, Shilim-dong, Kwanak-Gu, 151–742, Seoul, Korea.
Nak-Kyu Lee
Affiliation:
Micro Machining Technology Team, Industrial Technology Center, Korea Institute of Industrial Technology, 539–1, Gajwadong, Seogu, Incheon City, 404–253, Korea.
Kyung-Hoan Na
Affiliation:
Korea Institute of Industrial Technology, 35–3, HongChonRi, IbjangMyun, ChonAnsi, ChungNam, 330–32, Korea.
Dongil Kwon
Affiliation:
National Research Lab. for NanoAssessment & MicroReliability, School of Materials Science and Engineering, Seoul National University, San 56–1, Shilim-dong, Kwanak-Gu, 151–742, Seoul, Korea.
Get access

Abstract

We used an electronic speckle pattern interferometer (ESPI) for nondestructive measurement in-situ displacement fields in microsystems. A four-step phase-shift technique and magnifier with long working distance were adopted to increase displacement resolution to ∼10−2 μm and spatial resolution to ∼2 μm. A thermal vacuum chamber was designed to induce thermal treatments, including annealing. From the identification of the residual-stress-free state, we quantitatively modeled thermal strains/stress fields, relaxation stresses during annealing, and residual stress fields. Thermoelasticity theory was applied to model the relationship between the relaxation stresses and the displacements measured by ESPI during the evolution of the residual-stress-free state. We assessed the surface residual stress fields of indented bulk Cu; a Fe-Ni lead frame of 100 μm width; and 0.5 μm Au film. In the indented Cu, the normal and shear residual stresses around the indented point range from –1.7 GPa to 700 MPa and –800 MPa to 600 MPa, respectively, and the residual stress in the bending area of the Fe-Ni lead frame was estimated at 148 MPa and verified using beam-bending theory. In the Au film, tensile residual stresses are uniformly distributed from 500 MPa to 800 MPa as verified by X-ray diffraction.

Type
Research Article
Copyright
Copyright © Materials Research Society 2004

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. Nelson, D.V. and Makino, A., Opt. Lasers Eng. 27, 3 (1997).Google Scholar
2. Lira, I.H., Vial, C. and Robinson, K., Meas. Sci. Technol. 8, 1250 (1997).Google Scholar
3. Kämpfe, B., Mater. Sci. Eng. A, 288(2), 119 (2000).Google Scholar
4. Tanala, E., Bourse, G., Fremiot, M. and De Belleval, J.F., NDT & E Int. 28(2), 83 (1995).Google Scholar
5. Webster, G.A. and Wimpory, R.C., J. Mater. Process. Technol. 117(3), 395 (2001).Google Scholar
6. Gauthier, J., Krause, T.W. and Atherton, D.L., NDT&E Int. 31(1), 23 (1998).Google Scholar
7. Cloud, G.L., “Optical Methods of Engineering Analysis,” (Cambridge University Press, 1995).Google Scholar
8. Creath, K., Appl. Opt. 24, 3053 (1985).Google Scholar
9. Timoshenko, S.P. and Goodier, J.N., “Theory of elasticity (3rd-ed)” (McGraw-Hill, 1970) pp. 433484.Google Scholar
10. Fuchiyama, T. and Noda, N., JSAE Review, 16, 263 (1995).Google Scholar