Roles of imposed cyclic strain amplitude and cyclic strain rate on the stress relaxation behaviour of pre‐strained eutectic Sn‐3.5Ag solder joints
Abstract
Purpose
To understand the roles of service‐related parameters, such as imposed cyclic strain amplitude and cyclic strain rate, on the stress relaxation behaviour of eutectic Sn‐Ag solder joints.
Design/methodology/approach
Cyclic shear straining with associated stress relaxation at the shear strain extremes imposed was carried out on pre‐strained eutectic Sn‐Ag solder joints with various cyclic shear straining conditions. Results from such experiments were compared with previously reported findings from monotonic shear straining and stress relaxation tests.
Findings
At higher testing temperatures with a larger cyclic strain amplitude, stress states realized at the subsequent cycle are comparable with, or even gradually increase on, those experienced at the previous cycle, especially after few cycles. The maximum shear stress obtained at each cycle and residual stress during stress relaxation are strongly affected by cyclic strain rate. Stress relaxation during subsequent cycles of straining was found to be strongly dependent on the test temperature, and the imposed cyclic strain amplitude and cyclic strain rate.
Originality/value
In this paper, the experiments were carried out on eutectic Sn‐Ag solder joints with about a 100 μm joint thickness, which are, therefore, representative of those used in microelectronics. Also, there is no systematic study reporting the effects of cyclic straining conditions on the stress relaxation behaviour of eutectic Sn‐Ag solder for this joint configuration in the published literature.
Keywords
Citation
Rhee, H. and Subramanian, K.N. (2006), "Roles of imposed cyclic strain amplitude and cyclic strain rate on the stress relaxation behaviour of pre‐strained eutectic Sn‐3.5Ag solder joints", Soldering & Surface Mount Technology, Vol. 18 No. 1, pp. 19-28. https://doi.org/10.1108/09540910610647080
Publisher
:Emerald Group Publishing Limited
Copyright © 2006, Emerald Group Publishing Limited