Fig. 24 Extensive surface cracking was observed at the crack origin More

Fig. 27 Near-surface cracking present on a heavily abraded mining component. Continued abrasion after intergranular crack formation has deflected the perpendicular cracks. Unetched. 30× More

Fig. 4 Optical micrographs showing ingress of surface cracks in the transverse section of the failed bearing sample. (a) Contour of surface crack, 100×; (b) Crack contour with angular alumina inclusions, 500×; (c) Crack region with alumina particles, 1000× More

Fig. 3 Hardened structure associated with surface cracks. (×100). More

Fig. 6 Surface cracks in loop. 10 × More

Fig. 15 Surface cracks on bent section of Rod “A”; black arrows indicate longitudinal direction; red arrow indicates an incipient crack More

Fig. 3 Surface cracks on the thread of the screw: without metallo-graphic etching More

Fig. 4 Closer view of Fig. 3 . Gaping surface crack. Typical dimensions of this decohesion of material were 3 mm in circumferential direction and 2.5 mm crack depth More

Fig. 5 Cross section of failed edge, showing penetration of surface cracks and scale buildup. 42.2×. More

Fig. 2 Brittle transgranular fracture surface crack produced by inservice failure. More

Fig. 111 Microstructure of chain with intergranular surface crack. Nital etch. Original magnification: 1000× More

Fig. 112 Scanning electron microscope image of surface crack indicating intergranular fracture. Original magnification: 350× More

Fig. 74 Deep surface cracks that developed during a bending operation of a low-carbon steel. Courtesy of Worthington Industries Inc. More

Fig. 42 Fully pearlitic steel fatigue fracture surfaces. Crack growth direction is from left to right in both images. (a) Intermediate crack growth rate (∼0.1 ∼m/cycle), and (b) low crack growth rate (∼0.001 ∼m/cycle). No fatigue striations were resolved by SEM at any crack growth rate More

Fig. 3 SEM fractograph of spalled surface showing brittle intergranular cracking. 1000× More

Fig. 3 Form of cracking from internal surface (× 50). More

Fig. 16 Cracking, deformation, and a white hardened layer at the journal surface of Crank #1 More

Fig. 7 Cracking from undulations of bore surface. (×400). More

Fig. 8 Cracking from undulations of bore surface. (×400). More

Fig. 5 Cracking from surface corrosion pit. (×100) More