Analysis of Interface Stress of Sn3.5Ag0.75Cu Solder under Temperature Cycle QFP Device

Abstract:

Using elastoplastic finite element method study the interface stress distribution of Sn3.5Ag0.75Cu lead-free solder at different temperatures and different strain rate. Numerical analysis results show that: when strain-rate is identical, as the temperature rises, the interface stress increased rapidly of Sn3.5Ag0.75Cu lead-free solder and the substrate binding sites, from 11 °C when 2.6MPa rose to 90 °C in 49.7MPa, so the temperature is very large have effects of the interface stress of the lead-free solder and the substrate binding sites; when the temperature is constant, as the strain rate increases, Sn3.5Ag0.75Cu lead-free solder and the substrate binding sites of the interface stress showed a slight increase, from 0.005% / S when the 49.47MPa rose to 0.005% / S when the 50.08MPa, so strain rate on lead-free solder and the substrate binding sites of the interface stress effect is very small, indicating Sn3 .5Ag0.75Cu lead-free solder has strong rate-independent nature.

• Periodical: Applied Mechanics and Materials (Volumes 55-57)
• Pages: 1468-1472
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.55-57.1468
• Online since: May 2011
• Authors: Zhi Li, Cheng Ping Zhang, Mei Rong Zhao, Hai Jun Jin
• Keywords: Nature of Rate-Independent, Sn3.5Ag0.75Cu, Strain Rate, Stress Distribution, Thermal Cycling

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