Strain-mapping

QCBED (determination of space-group, cell constants, strain mapping, charge-density measurement)... 

Key words Electron Diffraction, CBED, Charge Density, Strain Mapping... 

The ability to obtain overall strain maps of specimens that are too distorted for individual defects to be distinguished. 

Enabled by the high resolution of spectra, which is enhanced by the use of spatial filter assembly having a small (200 pm) pin hole, the principle of the strain-induced band shift in Raman spectra has been further extended to the measurement of residual thermal shrinkage stresses in model composites (Young et al., 1989 Filiou et al., 1992). The strain mapping technique within the fibers is employed to study the... 

Galiotis C., Melanitis, N., Batchelder D.N., Robinson I.M. and Peacock J.A. (1988). Residual strain mapping in carbon fiber PEEK composites. Composites 19, 321-324. 

Kanzaki H, Bazaz R, Schwartzman D, Dohi K, Sade LE, Gorcsan J, III. A mechanism for immediate reduction in mitral regurgitation after cardiac resynchronization therapy insights from mechanical activation strain mapping. J. Am. Coll. Cardiol. 2004 44 1619-25. 

Fig. 17.4. Typical near-surface oxidation maps as measured in the non-wear and main wear zones, and strain maps as measured in the wear zone of UHMWPE-retrieved acetabular cups (a) 25 years and 3 months exposure in vivo and (b) 17 years and 9 months exposure in vivo. The linear dimensions of the map and the collection depth of the focal plane in confocal probe configuration are also explicitly shown...

Strain mapping and deformation analysis of "L " type joints. 

Figure 6a, b. Strain maps for the specimen with a fillet from Figure 5. Load P3 = 20N/inm.

Figure 7. Strain maps for specimen without a fillet and with a 0.5 mm crack (effective crack length a = 4.8 mm). Load P3 = lON/mm.

The tensile tests have been accompanied by acoustic emission (AE) registration, fuU-field surface strain-mapping (SM), progressive crack imaging at different load levels and micrographic inspection of the cross-sections of samples. The results of testing have been reported in [108,109]. 

Ivanov DS, Ivanov SG, Lomov SV, Verpoest I. Strain mapping analysis of textile composites. Opt Lasers Eng 2009 47 360-70. 

Most of the experimental results obtained confirm the stress or strain profile along the fibre length in agreement with Cox approach (Figure 7). However, interfacial failure at the fibre ends modifies the strain profile and thus can be directly evidenced by Raman spectrometry. Moreover, the state of strain (strain mapping) of fibres into real composite due to residual thermal stresses can also be determined. 

The application of Raman spectroscopy to the study of semiconductors is an area of interest with a long history from the perspective of both QC and failure analysis. The general applicability of Raman spectroscopy to semiconductors is covered in depth in Chapter 12 and has been the subject of a number of articles and reviews [154-157]. During the last 10 years, the opportunity to move beyond the research Raman microscopes for materials research to Raman analyzers for QC analysis has been explored. Some of the major areas of interest from a quality control/failure analysis standpoint are contamination, defect identification, materials characterization, and strain mapping at interfaces (between components and between silicon and attached circuitry). 

Various examples of using these materials for surface strain mapping have been presented in a recent publication [69]. The determination of stress concentrations around defects such as holes or notches in a deformed plate of the copolyurethane is shown in Figure 8.11. A circular hole and a notch of predetermined dimensions were accurately machined into a 3 mm thick specimen of the copolymer. The specimen was deformed in tension in the Raman spec-... 

Ulvestad A, Singer A, Cho H-M et al (2014) Single Particle Nanomechanics in operando batteries via lensless strain mapping. Nano Lett. doi 10.1021/nl501858u... 

Fig. 12 Contour maps of strain mapped over the graphene monolayer in a model composite. Maps are shown for the original flake before coating with the top polymer layer and then after coating with the top polymer layer at different levels of matrix strain indicated. (After ref 132.)... 

Wernle J, Gilbert JL. Three dimensional strain mapping of single asperity wear in UHMWPE effects of load and material on surface mechanical properties. Biomaterials 2008. In Press. 

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