抄録
Crack propagation tests of lead-free solder were conducted using center-notched plates under cyclic tension-compression of five strain waveforms: pp waveform having fast loading and unloading, cc waveform with slow loading and unloading, cp waveform having slow loading and fast unloading, and pa waveform with fast loading and slow unloading, also th waveform with tension hold, and thch waveform with tension and compression holds. Fatigue and creep components of J integrals were evaluated from the load displacements relations using simple estimates. For fatigue loading of pp wavefonn, the crack propagation rate was expressed as a power function of the fatigue I integral. The creep component due to the hold time greatly accelerates the crack propagation rate. The creep crack propagation rate was expressed as a power function of the creep J integral for each case of cp and cc waveforms. The crack propagation rate for cp waveform is higher than that for cc waveform.
