

A Kind of Physics Interpretations of Material Length Scales
Abstract
In the present research, a new mechanics model is presented and used to characterize the trans-scale mechanical behavior from nano-scale to macroscopic scale. In the mechanics model, both surface effect and strain gradient effect are considered. In order to interpret the physics meanings of the material length parameters included in the mechanics model, a new method will be used to represent the length parameters and a clear physics interpretation is obtained. Specifically, we use both the strain gradient theory and the Cauchy-Born rule to characterize the mechanics behaviors and then make a linkage for both kinds of results according to equivalence of strain energy densities. The values of the materials length parameters included in the strain gradient theory are expressed with the physics parameters included in the Cauchy-Born rule. As the example, for the face-centered cubic metals, the values and variation trends of the length scale parameters are obtained.
Keywords
Mechanical behavior; Length scale; Surface effect; Strain gradient effect; Cauchy-Born ruleText