Fig. 5.
Turning off the hard phase network and its effect on fatigue behavior. (A) The experimental protocol to turn off the hard phase network: The unnotched PA-5 sample is first preloaded at λpre = 3.44 (>λaffine) for 1,000 cycles, then a notch is made and fatigue test is performed at λmax = 2.54 (<λaffine). For comparison, a sample with λpre = 2.74 (<λaffine) is also studied. The hollow arrows indicate cyclic loading. The single-line arrow indicates that fatigue test for notched sample is performed after the cyclic preloading. (B) Fatigue experimental results for samples experienced different preloading: blue, λpre = 3.44 (>λaffine) with ruptured hard phase network; red, λpre = 2.74 (<λaffine) with undamaged hard phase network; and black, pristine sample without preloading.