Theoretical Investigations of the Behavior of Brittle Materials at Various Ranges of Temperature.

Abstract

A general non-linear law of material behavior was developed with the assumptions that the energy density of an isotropic material is invariant under the orthogonal group of transformations and that hydrostatic pressure produces only a volume change. For materials with crystal lattices, the energy density is assumed to be invariant under the crystalline group. This general law allows for the effects of thermal processes. Equations which are generalizations of the Beltrami equations and of the equation of heat conduction are stated to permit the determination of the unknown displacements and the temperature. These laws are very important in the use of brittl materials. As a part of the research, a non-linear thermodynamic theory for materials is established. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1971
Accession Number
AD0730352

Entities

People

  • E. H. Udo Wegner

Organizations

  • University of Stuttgart

Tags

DTIC Thesaurus Topics

  • Crystal Lattices
  • Crystals
  • Displacement
  • Dynamic Pressure
  • Equations
  • Hydrostatic Pressure
  • Materials
  • Static Pressure

Readers

  • Calculus or Mathematical Analysis
  • Materials Science and Engineering.
  • Thermal Physics or Thermal Science.