Dislocation-loop-length distribution and frequency-dependent damping for small impurity concentrations
- 1 February 1980
- journal article
- research article
- Published by Taylor & Francis in Philosophical Magazine A
- Vol. 41 (2) , 219-224
- https://doi.org/10.1080/01418618008236137
Abstract
For calculating effects such as Granato-Lücke dislocation damping, a distribution function for loop lengths of dislocation bowing out under an external stress is needed. Koehler's equation for a statistical distribution of pinning points ignores the nodes of the dislocation network. This means that it becomes inapplicable for small concentrations of impurity pinning points. In this paper a new equation is derived which takes into account a statistical distribution of pinning points and equally spaced nodes. A second equation with the vibrational entropy allowed for will hold only approximately. Both equations are applicable for all impurity concentrations down to zero. Granato-Lücke frequency-dependent internal friction, and the modulus defect as calculated from the first equation, are compared to that calculated from Koehler's distribution. A distribution of network lengths may easily be included.Keywords
This publication has 3 references indexed in Scilit:
- Calculation of granato-lücke frequency dependent internal friction as influenced by prolonged vibrationPhilosophical Magazine, 1966
- The free energy of a pinned dislocationPhilosophical Magazine, 1965
- Theory of Mechanical Damping Due to DislocationsJournal of Applied Physics, 1956