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Strain-destruction relationship

Such information offers an opportunity to study details of the fibrillation mechanism. The fibers formed by stretching the spherulitic polymer representing nothing other than ribbon formations plastically deformed and oriented towards the mechanical stress that is released by comparatively weak mutual interconditions existing in an earlier formation (Figure 3). This behavior points to the existence of some weak surfaces in the crystalline polymers. Elements of the super-molecular structure detached by action of the external mechanical forces can slide on the weak surfaces. Evidence for the strain-destruction relationship must come from studies of the modification of the contact surfaces of two neighboring spherulites under mechanical stress. [Pg.83]

Using solid-state physics and physical metallurgy concepts, advanced non-destructive electronic tools can be developed to rapidly characterize material properties. Non-destructive tools operate at the electronic level, therefore assessing the electronic structure of the material and any perturbations in the structure due to crystallinity, defects, microstructural phases and their features, manufacturing and processing, and service-induced strains.1 Electronic, magnetic, and elastic properties have all been correlated to fundamental properties of materials.2 5 An analysis of the relationship of physics to properties can be found in Olson et al.1... [Pg.201]

Because this kind of reaction takes place at low temperatures, thermal oscillations do not essentially contribute to backbone stretching. In fact, Ea is zero in this case. When Ea of bond scission is less than that required to form the active particles, cracking exhibits the character of a mechanically activated chemical reaction—chain scission in active particles takes place. There is a cause-and-effect relationship between the strain processes (which are cumulative in the deformed fragment to activate the backbone) and the destruction processes. [Pg.81]

The use of the electric field has been proposed and demonstrated to perform very well in defining various other properties. For example, electrical measurements have been used to monitor the foaming process and polymerization of polymeric foams [74], while dielectric measurements have been used for measuring the density of polymer foams [75]. Brady et al. [76] developed electrically conductive polypyrrole-coated PUR foam. The conductance of the foam was found to change linearly with the compressive load applied single and repeated. For aluminum foams, Kim et al. [77] developed a set of mathematical relationships based on experimental data to obtain mechanical properties (elastic modulus, compressive strength, and densification strain), using electrical conductivity as a non-destructive inspection method. [Pg.87]


See other pages where Strain-destruction relationship is mentioned: [Pg.28]    [Pg.198]    [Pg.23]    [Pg.1609]    [Pg.403]   
See also in sourсe #XX -- [ Pg.71 ]




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