Thermodynamics properties of crystals containing imperfections

Using thermodynamics and elasticity theory, a unified treatment of changes in the properties of crystals containing the major types of defects is given. Some previously derived results are recovered in the present calculations, such as the formula for volume changes of self-stressed media derived by Zener. However the present results are of a more general nature and the method is not restricted to static, isotropic, elastic systems at zero pressure. For defects described by elastic strains, it is shown that the required pressure and temperature dependence is given by using the known pressure and temperature dependent elastic constants in place of the zero pressure elastic constants in the linear elasticity results. The general results are specialized to a number of particular defects by using models to find expressions for the energy required to form the defect, so that the thermodynamic properties can be calculated. Also thermal properties are computed by treating phonons as defects on the same basis as other defects. A number of measurements of the properties of crystals containing defects are discussed in relation to the present calculations. For the case of dislocations, where the calculations are most soundly based~ there are relatively few measurements available. On the other hand, for the discussion of the large volume of measurements available of the effects of point defects, there is no generally acceptable model for the Gibbs free energy. For dislocated crystals, a number of specific predictions are made, some of which are partially confirmed by the available data. The extent to which the properties of crystals containing point defects could be correlated on the basis of one model is explored.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Year dc:date

2011

Author dc:creator

• Holder, Jon Thomas

Contributors dc:contributor

• Granato, A.V.

• thermodynamic properties
• cystals containing imperfections
• elasticity theory

Statement dc:rights

• 1968 Jon Thomas Holder

Language dc:language

en

Identifier

6079143

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/25734