Solder-joint reliability in electronics under shock and vibration using explicit finite-element sub-modeling

• Published in: 56th Electronic Components and Technology Conference 2006 p. 8 pp.
• Main Authors: Lall, P., Gupte, S., Choudhary, P., Suhling, J.
• Format: Conference Proceeding
• Language: English
• Published: IEEE 2006
• Subjects: Assembly; Computational modeling; Displacement measurement; Electric shock; Finite element methods; History; Predictive models; Solid modeling; Strain measurement; Testing
• ISBN: 1424401526; 9781424401529
• ISSN: 0569-5503
• DOI: 10.1109/ECTC.2006.1645682

In this paper, the modeling approaches for first-level solder interconnects in shock and drop of electronics assemblies have been developed without any assumptions of geometric-symmetry or loading symmetry. The problem involves multiple scales from macro-scale transient-dynamics of electronic assembly to micro-structural damage history of interconnects. Previous modeling approaches include, solid-to-solid sub-modeling (Zhu et. al., 2001) using a half test PCB board, shell-to-solid sub-modeling technique using a quarter-symmetry model (Ren et. al., 2003; 2004). Inclusion of model symmetry in state-of-art models saves computational time, but targets primarily symmetric mode shapes. The modeling approach proposed in this paper enables prediction of both symmetric and anti-symmetric modes, which may dominate an actual drop-event. Approaches investigated include, smeared property models, Timoshenko-beam element models, explicit sub-models, and continuum-shell models. Transient dynamic behavior of the board assemblies in free and JEDEC-drop has been measured using high-speed strain and displacement measurements. Model predictions have been correlated with experimental data