As the defect amounts increase, we see a larger build up of stress on the right hand side with both higher level stress covering more area and darker red stress regions present. As the crack grows towards the end of the Yaxis of the material for 15 and 17 defects, a build up of stress is present due to no more material for the crack to propagate through. This explains the much darker red region present at the higher defect amounts. Along with this, we see how the stress is much more separated at Above we observe an overall comparison of the 25 • at 0.04 Interface Toughness cases with the only changing variable being that of the defect density. We have included each of the defect densities ranging from 5-17 Fig. : Elastic Energy Peak is for differing defect cases from 0 -17 defects.