A fracture surface

Figure C2.11.5. Scanning electron micrographs showing the microstmcture of an alumina ceramic spark-plug body (a) fracture surface and (b) polished and thennally etched cross section.

Fig. 11. Micrographs of (a) a hot-pressed alumina—TiC ceramic showing a white TiC phase and a dark alumina phase (3) and (b) a fracture surface of an...

Figure 6.18 A stereoscan of a fracture surface of a dental silicate cement. The debonded glass particle is to be identified by its pitted surface, the result of selective acid attack. Note the particulate nature of the matrix (Wilson et at., 1972).

Fig. 10. Scanning electron micrograph of a fracture surface parallel to the direction of extrusion of an extrudate of a 45 55 PS-HDPE blend with a viscosity ratio p 1. Fibrous PS is shown at different stages of breakup the diameter of the largest fiber is about 1 pm (Meijer el til., 1988).

To look for small voids, SEM was used. For the cracked sample, a fracture surface was examined, while a cut surface of the good sample was studied. This test showed large differences between the two samples with the cracked part showing significant voids. Figure 43(a) shows an SEM micrograph for the good... 

The presence of metal oxide on both sides of a fracture surface can be deceptive if the surface has microroughness (peaks less than 1 fim high), since the failure... 

Figure 7. ATR spectra using the 45° KRS-5 reflection element. (A) Fracture surface, primed sample (B) fracture surface, unprimed sample (C) difference between (A) and (B).

Ciyo-SEM methodology also facilitates the observation of highly hydrated systems. Harker and Sutherland [69] used the ability of cryo-SEM to preserve the structural integrity of the aqueous phase to characterize differences between mealy and non-mealy nectarines. The presence of juice on the surface of cells in non-mealy nectarines was observed after tensile tests produced a fractured surface. Such observations would not have been possible with conventional methods where dehydration and critical point drying are essential steps. A strong point to this study was the extensive use of other physical and chemical methodologies to help correlate textural difference based on storage parameters for nectarines. 

Internal cavitation was proved by comparison of the initial particle diameter with the diameter measured on a fracture surface (Huang et al., 1993b). An increase of about 20-70% of the initial volume was found, depending on the temperature. This voiding process participates in the energy consumption and is the cause of the stress whitening effect observed on deformed samples. 

Fracture surface of a three-layered tile (a) interface between B4C-30wt%SiC outer layer and pure B4C inner layer (b) a fracture surface of B4C layer (c) fracture surface of B4C-30wt%SiC ... 

SEM (secondary electrons) micrograph of a fracture surface from a Cu-Al203 nanocomposite. The Cu particles occupy intergranular positions and the fracture observed is mostly intergranular. 

Figure 1.8. Scanning electron micrograph of a fracture surface through crown dentin of a human tooth. Various tubules are viewed in cross section. The dense envelope around the tubules is composed of peritubular dentin (PT). Intertubular dentin (ID) is...

An electron micrograph of a fracture surface of a CTBN-toughened epoxy resin is shown in Figure 5. This CTBN is particular in that the in situ formed particles are less than 0.5 /zm in diameter. A tensile bar of this system also shows shear deformation which indicate that the small particles have not interfered with the shear deformation characteristic of the unmodified resin. The deformation bands are nearly parallel to the planes of maximum shear stress—i.e., roughly at 45° to the principal... 

All of the SAN samples, whether of 25% or 30% AN tested in fatigue at 21 Hz, displayed a fracture surface morphology that was in some respects akin to that of PS and in other respects quite different. Like PS, fracture developed from a surface source and the region surrounding the source was comparatively smooth but, unlike PS tested at this frequency, discontinuous growth bands were seen in this region. 

J. J. Berzelius said anhydrous potassium trisulphide appears in yellowish-brown masses which, said H, E. Schone, show the presence of prismatic crystals on a fractured surface. W. Biltz and E. Wilke-Dorfurt say the anhydrous... 

Figure 3. X-ray photoelectron spectra of a fractured surface of arsenopyrite after 8 hours reaction with distilled water. Narrow scan spectra are presented for (a) 0(ls), (b) S(2ps/p, (c), Fe(2pi/f), and (d), As(3d /2). XPS data are the black squares, the fit is the thick black line, the background and XPS peaks by thin solid lines, and peak doublets by dashed lines. Reprintedfrom Nesbitt et al. (1995) with permission.

Fig. 10 shows a fractured surface of autoclave-cured PAO composite and Fig. 11 shows one of autoclave-cured PA1. There appears smooth surface of A3 silica sand or FRP powder, which may suggest the same effect to multiple cracks in the early stage of bending. 

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