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Publication Date

Summer 2014

Degree Type

Thesis - Campus Access Only

Degree Name

Master of Science (MS)


Biomedical, Chemical & Materials Engineering


Guna Selvaduray

Subject Areas

Biomedical engineering


An experimental investigation was conducted to characterize and measure the contributions of shear and tensile strain components to the overall creep behavior of solder joints. Each copper substrate test vehicle consisted of two halved dog-bone shaped coupons and formed a butt joint at 0°, 30°, 45°, 60°, and 90° angles. Eutectic Pb-63Sn solder and Sn3.0Ag0.5Cu (SAC 305) lead-free solder alloy were used to solder the coupons. The specimens were subjected to 5.2 MPa tensile stress for three days in a thermal chamber at 25°C, 37°C, and 100°C. The experimental results revealed that both tensile creep strains and shear creep strains contribute to the combined creep curves. For both Pb-63Sn and SAC 305 solder joints, the contributions of both tensile strains and shear strains to combined strains were found to be significant. Thus, the orientations of angles have a significant impact on the creep behavior of solder joints. The creep resistance of the SAC 305 solder joints was greater than that of the Pb-63Sn solder joints for all the conditions tested.