Journal of Materials Engineering and Performance

, Volume 22, Issue 4, pp 1186–1193 | Cite as

Nonlinear Viscoelastic Characteristics of Sn-Ag-Cu Solder Pastes Used in Electronics Assembly Applications

  • Sabuj MallikEmail author
  • Erica Hiu Laam Chan
  • Ndy Ekere


Sn-Ag-Cu solder pastes are widely used as the joining material in the electronic assembly process. The aim of this work was to evaluate the nonlinear viscoelastic behaviors of three different Sn-Ag-Cu solder pastes. Three novel rheological test methods were developed for this purpose. These include viscosity, thixotropic loop, and oscillatory amplitude sweep tests. The nonlinear flow curves obtained from the viscosity tests revealed the “shear-thinning” behavior of solder paste samples. Thixotropic loop test results explain the time-dependent structural breakdown and recovery of solder pastes. The viscoelastic properties of solder pastes were interpreted through oscillatory test parameters: storage modulus (G′), loss modulus (G″), and phase angle (δ). The discrepancies observed in the rheological behaviors of the paste samples were found to be related with flux composition (liquid phase in the solder paste) and particle size distribution.


nonlinear flow rheology suspension solder paste viscoelasticity 


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Copyright information

© ASM International 2012

Authors and Affiliations

  • Sabuj Mallik
    • 1
    Email author
  • Erica Hiu Laam Chan
    • 2
  • Ndy Ekere
    • 1
  1. 1.Manufacturing Engineering Research Group, School of EngineeringUniversity of GreenwichChathamUK
  2. 2.Department of Physics and Materials Science, College of Science and EngineeringCity University of Hong KongHong KongHong Kong

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