... solders are sparse, especially regarding performance at cold temperatures. We report Garofalo creep data for 83Pb/10Sb/5Sn/2Ag (Indalloy 236) and 91.5Sn/8.5Sb (Indalloy 264). Indalloy 236 exhibits an activation energy of 54.5 kJ/mol, n = 4.5, and α = 0.043 while Indalloy 264 exhibits an activation energy...

... affecting the fatigue life of solder joints, which are: plastic strain-based fatigue models, creep damage-based fatigue models, energy-based fatigue models, and damage accumulation-based fatigue models. The models that do not fit any of the above categories are grouped into “other models.” Applications...

...Yongchang Lee; Cemal Basaran Demand for long-term reliability of electronic packaging has lead to a large number of studies on viscoplastic behavior of solder alloys. Various creep models for solder alloys have been proposed. They range from purely empirical to mechanism based models where...

... in the tensile region is different from that in the compressive region is employed for the fatigue test. Different fatigue lives due to different strain rates in the tensile and compression regions originate from the difference of development behaviors of creep strain generated in the cyclic loading. This paper...

...Ken-ichi Ohguchi; Katsuhiko Sasaki We previously proposed an elastic-plastic-creep model to estimate the fatigue strength of lead-free solder joints subjected to cyclic thermal loading. The proposed model requires detailed experimental data regarding the time-independent plastic strain and the time...

...Ken-ichi Ohguchi; Katsuhiko Sasaki; Setsuo Aso This paper proposes a method to estimate basic material constants in an elasto-plastic-creep constitutive model for lead-free solders by conducting only a tensile test. The test employs a stepped ramp wave loading, which repeats instantaneous strain...

...Min Pei; Jianmin Qu In this paper, a microstructure-dependent creep model is developed that accounts for the hierarchal microstructure at multiple length scales. The model considers three distinguishable phases in the solder alloy at two different length scales: at the larger scale Sn dendrites...

... such as the Coffin–Manson rule have helped us identify reliable choices among package design alternatives. However, for the currently popular Pb-free choice of SnAgCu solder joints, designing accelerated thermal cycling tests and estimating the fatigue life are challenged by the significantly different creep...

..., which focuses on the details of damage initiation and propagation in the individual solder ball. The local model is error seeded with voids based on cases selected in experiment. The damage propagation rate is monitored for all the cases. The technique used to quantify cyclic creep-fatigue damage...

...David M. Pierce; Sheri D. Sheppard; Arlo F. Fossum; Paul T. Vianco; Mike K. Neilsen A unified creep plasticity damage (UCPD) constitutive model was developed to predict the fatigue of 95.5Sn–3.9Ag–0.6Cu solder joints. Compression, stress-strain and creep properties were generated in previous...

... simulated analyses of creep, plastic, and plastic-creep behavior on the WLCSP assemblies. It is found that the temperature dwell is the most significant factor on the effects of shear strain range from these analyses. The effect of high temperature dwell on the shear strain range is larger than that of low...

...David M. Pierce; Sheri D. Sheppard; Paul T. Vianco; Jerome A. Regent; J. Mark Grazier A general fatigue life prediction methodology, based on a unified creep plasticity damage (UCPD) model, was developed for predicting fatigue cracks in 95.5Sn–3.9Ag–0.6Cu (wt %) solder interconnects...

... material testing system, with solder alloys subjected to a variety of complex load conditions: pure shearing at strain rates between 6.7 × 10 − 7 ∕ s and 1.3 × 10 − 1 ∕ s , creep at temperatures ranging from room temperature up to 125 ° C , and cyclic loading with frequencies of 0.001 Hz to 3 Hz . Biaxial...

...-parameter Weibull distributions with life test data of an 1657-pin CCGA package with the 95.5 wt %Sn3.9 wt %Ag0.6 wt %Cu lead-free solder paste on lead-free printed circuit boards under thermal cycling conditions. The other part of this study is to determine the time-history creep strain energy density...

...Ahmad Abu Obaid; Jay G. Sloan; Mark A. Lamontia; Antonio Paesano; Subhotosh Khan; John J. Gillespie, Jr. The objective of this work was to experimentally determine the in situ creep behavior and constitutive model equations for a commercial area array package and printed wiring board assembly...

... data. The developed mapping methodology is employed to design alternate accelerated thermal cycles by matching the creep and plastic strain contributions to total inelastic strain accumulation in solder under military field-use and accelerated thermal cycling environments, while reducing the time...

... thermodynamics. A series of uniaxial tension, tensile creep, and strain-controlled fatigue experiments are performed to obtain material parameters for the solder damage model. The solder damage model is then implemented into a finite element code and used to simulate a uniaxial tension test on a miniature...

...S. Wiese; E. Meusel The creep and crack propagation behavior of SnAg3.5, SnAg4Cu0.5, and SnPb37 (as reference) was investigated on flip chip solder joints V = 1 × 10 − 12 m 3 . The test specimen consisted of two silicon chips (3.3×3.3 mm), bonded to each other by four flip chip joints (one on each...

...) simulations using isotropic and anisotropic properties of the die are carried out, respectively, and the results are compared. Creep experiments were performed at different temperatures ranging from −65°C to 230°C to obtain the long-term master curves and the related shift factors for the creep compliance...

..., assumptions concerning the homogeneity of the cyclic temperature fields, simplified creep characterization of solder, and the related application of Manson-Coffin failure criteria, are discussed in the paper. The packages chosen for detailed analyses are a PBGA 272 and a FC-CSP 230. Coefficients...