Hostname: page-component-84b7d79bbc-5lx2p Total loading time: 0 Render date: 2024-07-29T08:45:39.819Z Has data issue: false hasContentIssue false

Presence of Anelastic Strains in High Lead Solders at Ambient and High Temperatures

Published online by Cambridge University Press:  26 February 2011

J.K. Tien
Affiliation:
Strategic Materials R&D LaboratoryThe University of Texas at Austin Austin, TX 78712-1063
A.I. Attarwala
Affiliation:
Strategic Materials R&D LaboratoryThe University of Texas at Austin Austin, TX 78712-1063
Get access

Abstract

We had reported last year that cyclically tested Pb/Sn solders of different compositions exhibited a complicating anelastic effect. The storage and recovery of anelastic strains suppresses damaging creep strain from being stored thus causing non-conservative life prediction estimates and results in complications with respect to accelerated testing. These complications were at that time believed to be characteristic of only eutectic solders at near ambient temperatures. We now find that said complications exist for high end Pb solders and at higher temperatures. Strain rate behavior of high lead solders indicate that a different failure mechanism might exist at temperatures where the material exists as a two phase and in regimes where it exists as a solid solution. Experiments conducted to determine the effect of grain size on accelerated cycling indicated that recrystallization of large grains occurs due to cycling at high temperatures. At ambient temperature, which is greater than half the absolute melting temperature of 90/10 Pb/Sn, it was observed that large grains suppress creep.

Type
Research Article
Copyright
Copyright © Materials Research Society 1991

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

1. Tien, J.K., Hendrix, B.C., Attarwala, A.I., “Creep-Fatigue Interactions In Solders,” IEEE Trans. CHMT, vol. 12, No.4, Dec 1989 Google Scholar
2. Enke, N. F., Kilinski, T.J., Schroeder, S.A., Lesniak, J.R., “Mechanical Behavior of 60/40 Tin-Lead Solder Lap Joints,” Proceedings. 39th Electronic Components Conference, 1989, pp. 264272.Google Scholar
3. Solomon, H.D., , Creep, “Strain Rate Sensitivity, and Low-Cycle fatigue of 60/40 Solder,” Brazing and Soldering, vol. 11, pp. 6875 (1986).Google Scholar
4. Engelmaier, W., “Functional Cylces and Surface Mounting Attachment Reliability,” Circuit World, vol. 11, pp. 6169 (1985).Google Scholar
5. Tien, J.K., Hendrix, B.C., Attarwala, A.I., “Creep-Fatigue Damage and Anelastic Recovery of Solder,” Proceedings NEPCON WEST '90, vol. II, pp 13531360.Google Scholar
6. Weinbel, R.C., Tien, J.K., Pollak, R.A., Kang, S.K., “Creep Fatigue Interaction in Eutectic Lead-Tin Solder Alloy,” J. Mat. Sci., vol. 22, pp. 39013906 (1987).Google Scholar