Creep deformation mechanisms in tin, and Sn-3.SAg and Sn-5Sb electronic solder alloys, have been studied at various temperatures between ambient and 473 K. Power-law relationships between strain rate and stress were generally observed. Stress exponent n = 7.6 + - 0.2 5.0 + - 0.2 and 5.0 + - 0.3. and activation energy for creep Qc.= 60.3 + - 3.8, 60.7 + 16.6 and 44.7 + - 3.7 kJ/mole were obtained in the case of tin, Sn- 3.SAg and Sn-5Sb respectively. It is suggested that the rate controlling deformation mechanism is dislocation climb controlled by lattice diffusion in pure tin and Sn- 3.SAg alloy, and viscous glide controlled by pipe diffusion in Sn-SSb alloy. Sn-5Sb alloy is found to be more creep resistant than Sn-3.5Ag alloy. -
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