Creep deformation mechanisms in tin, and Sn-3.5Ag and Sn-5Sb electronic solder alloys, have been studied atvarious temperatures between ambient and 473 K. Power-lawrelationships between strain rate and stress were generallyobserved. Stress exponent n valence 7.6+-0.2 5.0+-0.2 and 5.0+-0.3, and activation energy for creep Q_c valence 60.3+-3.8,60.7+-6.6 and 44.7+-3.7 kJ/mole were obtained in the case of tin,Sn3.5Ag and Sn-5Sb respectively. It is suggested that the ratecontrolling deformation mechanism is dislocation climbcontrolled by lattice diffusion in pure tin and Sn3.5Ag alloy, andviscous glide controlled by pipe diffusion in Sn-5Sb alloy. Sn-5Sb alloy is found to be more creep resistant than Sn-3.5Ag alloy.
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