Micromechanics definition

The micromechanical definitions of and (Eq. (165)) then yield, after simple calculations ... 

N. P. Krayt and L. Rothenburg, Micromechanical definition of strain tensor for granular materials. ASME Journal of Applied Mechanics 118,706,1996. 

Micromechanics — The study of composite material behavior wherein the interaction of the constituent materials is examined in detail as part of the definition of the behavior of the heterogeneous composite material. 

Definitive studies of composite material tensile strength from a micromechanics viewpoint simply do not exist. Obviously, much work remains in this area before composite materials can be accurately designed, i.e., constituents chosen and proportioned to resist a specified tensile stress. 

The next problem area of micromechanics is initially very attractive in some respects. We look to the fundamental definition of a composite material made up in this case of, say, a fiber and a matrix and attempt to actually design that material. Let us change the proportions of fibers and matrix so that we get the kind of material behavior characteristics we want. That objective is admirable, but achieving that objective in all cases is not entirely realistic. 

Therefore, often main attention in studying chemical oscillations is paid to their formal description on the macroscopic level rather than to an attempt to understand in detail the micromechanism of oscillations. It often results in necessity to make a choice between several alternative models suggested for a particular chemical system. It is difficult to restrict ourselves in theory to a definite universal basic model since it can turn out to be either too complicated for studying a particular kind of the autowave processes or, on the other hand, of a limited use due to its inability to reproduce all types of auto-wave processes. 

Estimates for the macroscopic drained stiffness tensor Chom(f) as a function of the morphological parameter can be derived from various micromechanical techniques. The micromechanical approach classically refers to the concept of strain concentration tensor, denoted here by A. By definition, in an evolution... 

Thermoplastic cracking develops under certain conditions of stress and environment, sometimes on a microscale. Because there are no fibrils to connect surfaces in the fracture plane (except possibly at the crack tip), cracks do not transmit stress across their plane. Cracks result from embrittlement, which is promoted by sustained elevated temperatures and ultraviolet, thermal, and chemical environments existing in the presence of stress or strain. There appears to be no practical definition that can sufficiently distinguish between environmental and other stress cracking, although the micromechanics of the two types of cracking may be quite different. 

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