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Crack propagation tests of lead-free solder were conducted using centercrackedplates for cyclic tension-compression and thin-walled tubular specimens forcyclic torsion. Both specimens have an initial notch as a crack starter. In fatigueloading with fast loading rates, the path of crack propagation under tensioncompressionwas macroscopically straight, perpendicular to the maximum principalstress direction. In tubular specimens under cyclic torsion, at the high strain range, thecrack propagate in shear mode II along the maximum shear direction. At low strainrange, four cracks are formed from the initial silt and propagate showingmacroscopically tensile mode. The introduction of creep components by tension holdpropromoted shear-mode crack propagation under tension compression. For fatigueloading, the crack propagation rate was expressed as a power function of the fatigue Jintegraland the relation was not much different between tension-compression andcyclic torsion. The tension hold, or the creep component, during tension-compressionloading greatly accelerates the crack propagation rate. Both cycle-dependent fatiguepropagation and time-dependent creep-fatigue propagation of cracks took place byjoining microcracks formed along the maximum shear planes ahead of the crack tip