Failure properties, definitions

The indentation confidence depth was determined to be a function of the coating to substrate yield strength ratio for three different substrate configurations. Tilbrook et al. (2007) incorporated microstructural failure mechanisms into finite element simulations of nanoindentation of TiN thin films on elastic—plastic substrates. Intergranular sliding that occurs as a result of the columnar grain structure is incorporated into the model via anisotropic property definitions and nodal coupling. 

Jenike (1964, 1970) has published a fundamental and widely used definition and shear testing protocol on the flowabiUty of powders. The failure properties of powders and thus flow are measured and calculated from a family of yield loci obtained from a number of shear tests. 

A precise definition of the term reinforcement is difficult because it depends somewhat on the experimental conditions and the intended effects of the filler addition...it appears preferable to regard reinforcement broadly as the modification of the viscoelastic and failure properties of a rubber by a filler to produce one or more favorable results... 

In many applications we consider the yield point of a polymer to be its point of failure. We base this definition on whether the material is still fit for its end use once it has yielded. Thus, if the teeth on a polymer gear wheel yield, they will change shape and may become useless. Alternatively, packaging film may yield, but still maintain its barrier properties and be fit for continued use. 

These examples indicate that it is necessary to keep the possible effect of point defects on bulk and mechanical properties in mind. Although less definitive than electronic and optical properties, they may make the difference in the success or failure of device operation. 

Failure occurs when the component ceases to perform its required function. In the case of catastrophic failure, such as the rupture of a pipe or electrical breakdown of an insulator, this is obvious, but in many cases there is no such clear end of life. For example, is the end point when a small amount of environmental stress cracking has occurred, or when cracks have reached 5 mm in length Broadly, the definition of end point is that a property has reached a level at which safety, performance or market acceptance dictate that the component or product can no longer be used. 

The appropriate definition of nonspecific binding is essential prior to characterization of the kinetic and equilibrium properties of the binding interaction. As a rule, nonspecific binding can be defined using a concentration of the unlabelled ligand that is 100 times its Ka value for the sites of interest. Failure to appropriately define nonspecific binding will invalidate the determination of the binding parameters. 

This document gives definitions of terms related to the non-ultimate mechanical behaviour or mechanical behaviour prior to failure of polymeric materials, in particular of bulk polymers and concentrated solutions and their elastic and viscoelastic properties. 

According to this definition, the failure to qualify as macroscopic can be traced to one or more properties that lack intensive or extensive character. This failure can usually be attributed to surface effects, i.e., to properties that still depend on the shape or size of the system in a nonextensive manner. We know that, for sufficiently large systems, the surface effects (which scale as r2) eventually become negligible compared with the bulk volume effects (which scale as r3). (Although the preceding remarks are specific to ordinary 3-dimensional systems, similar remarks apply to edge effects in 2-dimensional systems or end effects in 1-dimensional systems.) Empirically, we know that macroscopic character, once established, persists for all larger sizes. Hence, the operational definition above allows us to determine the smallest sample of S that still qualifies as macroscopic in a particular experimental framework. 

Fracture properties arguably are not rheological properties, but mechanical properties, given the standard definition of rheology (see above). However, failure of structure in foods, especially high-fat foods, usually begins at strains below the actual fracture point, the point at which the... 

In phenomenological non-equilibrium thermodynamics a complicated system is described by taking each flux as dependent on each of the forces within the system. On the other hand, common sense tells us that some processes will in practice not depend noticeably on some of the forces. In fact, it could almost be considered a definition of an independent process that it is independent of driving forces other than its own driving force. Thus, we can simplify the description by splitting it up into independent processes. It should always be remembered, however, that such independence of processes remains a postulate of the description failure to fit the properties of the system with the equations may be the result of an unnoticed coupling. 

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