Fig. 9 Fractograph taken from 2024-Al fracture surface replica. Arrows identify small constituent particles at the bottom of dimples that are the origin of the fracture process. Courtesy of Martinus Nijhoff Publishers. Source: Ref 21 More

Fig. 13 Transparent tape replica of a fracture surface. See the article “Transmission Electron Microscopy” in this Volume for more information on replication techniques. More

Fig. 14 Comparison of replica fractographs of a fatigue fracture in an induction-hardened 15B28 steel shaft. Fracture was initiated at the large inclusion in the center of the views during rotating bending. (a) Oblique illumination from a point source lamp. (b) Same area as (a), photographed More

Fig. 8 Palladium-shadowed plastic-carbon replica of a fracture in nickel showing reticulated shadowing metal on dimples. Reticulation was caused by the melting of the shadowing metal in the microscope and the formation of globules. 22,500× More

Fig. 402 TEM p-c replica from deep within the impact fracture area, B, in Fig. 397 , showing the quasi-cleavage characteristics of this brittle, untempered specimen. No large facets are visible; this suggests that the specimen had a fine grain size. Many steps exist in the crack path. 6500× More

Fig. 407 TEM p-c replica of a region near the right edge of the fracture surface in Fig. 405 , showing a transition from intergranular facets (at right) to dimples (at left). This transition is typical of all cracks in the actuator shaft that originated near holes, in each instance More

Fig. 416 TEM p-c replica of the fracture surface in Fig. 414 , showing a region 0.25 mm (0.01 in.) below the outer surface. The mixture of intergranular facets and dimples shown here is typical of some plane-strain fracture surfaces in AISI 4340 steel. 2100× More

Fig. 417 TEM p-c replica of the fracture surface in Fig. 414 , showing a region at the bottom of a depression directly below the surface crack. In this entire area of projections and depressions (see Fig. 414 ), fracture was completely intergranular. 1000× More

Fig. 616 TEM p-c replica of an area near A, close to the notch, in the fracture in Fig. 618 , showing definite cleavage steps and essentially no evidence of fatigue striations. A thin oxide film is present. See also Fig. 617 . 6500× More

Fig. 619 TEM p-c replica of a third area near A in the fracture surface shown in Fig. 618 . Here, fatigue striations are present in rather narrow and somewhat irregular patches. Some evidence of surface oxidation can be seen. 6500× More

Fig. 620 TEM p-c replica of a fourth area near A in the fracture surface in Fig. 618 , showing flat facets quite suggestive of intergranular cleavage. The parallel marks may not be fatigue striations, but rather features associated with the oxide film. 6500× More

Fig. 621 TEM p-c replica of a fifth area near A in the fracture surface in Fig. 618 . This area is characterized by narrow patches of extremely sharp and distinct fatigue striations. Again, the oxide film is apparent. 6500× More

Fig. 622 TEM p-c replica of a sixth area near A in the fracture surface in Fig. 618 , showing distinct fatigue striations. The markings to the right of the dark region are believed to be cleavage steps, not fatigue striations. 6500× More

Fig. 626 TEM p-c replica of an area at D, in the region of final fast fracture and about 11.7 mm (0.46 in.) from the notch, in Fig. 618 . The elongated dimples confirm that final fracture was by shear. Fatigue striations ceased to form when this final stage of fracture began. 6500× More

Fig. 713 TEM p-c replica of the fracture surface in Fig. 710 , showing a region about 30 μm from a crack nucleus. Visible between the arrows are steps that separate fatigue patches. Fatigue striations are faintly visible within the patches. 3750× More

Fig. 714 TEM p-c replica of the fracture surface in Fig. 711 , showing a region about 30 μm from the inner edge. This view shows generally flat fatigue patches that are separated by steps, but no fatigue striations are visible within the patches. 3750× More

Fig. 715 TEM p-c replica of the fracture surface in Fig. 710 , showing a region in the fatigue zone, but near the zone of final tensile-shear fracture. This replica reveals fatigue patches separated by steps and containing faint fatigue striations. 6125× More

Fig. 716 TEM p-c replica of a portion of the shear lip in the fracture surface in Fig. 710 , showing shear dimples, which resulted when microvoid coalescence occurred during final tensile-shear fracture. The dark areas are probably rust or “dirt.” 18750× More

Fig. 842 TEM p-c replica of a fracture surface of one of the turbine-rotor blades in Fig. 840 . This view is typical of all the areas examined. A patch of fatigue striations is faintly visible at center between arrows. The fatigue crack is believed to have been initiated by hot corrosion More

Fig. 1066 TEM p-c replica of an area of the fracture surface in Fig. 1060 near the edge at which fracture was initiated, showing corrosion debris on a very flat intergranular surface. The original separated-grain facets have been corroded away. 3000× More