“…The challenge, however, is that damage is a multiscale process particularly when the incubation and initiation phases are concerned, as shown for example in recent investigations on crack formation in metals undergoing fatigue loading [1][2][3]. Detailed considerations of the material's actual microstructure are shown to be crucial to their mechanical behavior during loading, as reported recently in steel [4], aluminum [5][6][7][8][9][10][11], magnesium [12][13][14][15][16], and titanium alloys [17,18] among others [2,3,19,20]. These materials span a range of crystalline structures and contain a number of initial defects from material processing [11], some of which include voids, precipitates, dislocations, and microcracks that can propagate and lead to damage at multiple length scales.…”