Journal ArticleDOI
Consideration of the existence of surface wave (Rayleigh wave) solutions in anisotropic elastic crystals
David M. Barnett,Jens Lothe +1 more
TLDR
In this paper, it was shown that a proper surface wave may always occur in a stable linear anisotropic half space provided that a certain real symmetric 3*3 matrix B is not positive definite for all velocities less than a limiting velocity nu L, the velocity at which bulk wave solutions first appear.Abstract:
From a previous analysis it is known that a proper surface wave may always occur in a stable linear anisotropic half space provided that a certain real symmetric 3*3 matrix B is not positive definite for all velocities less than a limiting velocity nu L, the velocity at which bulk wave solutions first appear. B is also the lagrangian factor matrix for a particular straight dislocation moving uniformly in an infinite medium which is elastically identical to the half space. By examining the behaviour of the dislocation lagrangian and the eigenvalues of B at nu L, it is proved that proper surface waves may always occur except in cetain special cases. In each special case there always exists at least one bulk wave solution which satisfies the free surface condition on the half space boundary. Thus, there exist no forbidden directions for steady state propagation satisfying the free surface condition, i.e. either a proper (attenuated) surface wave and/or an unattenuated 'bulk surface wave' solution is possible. One simple numerical integration suffices to determine if a given propagation direction admits a proper surface solution.read more
Citations
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Journal ArticleDOI
Anisotropic continuum theory of lattice defects
Book ChapterDOI
Foundations of the Theory of Surface Waves in Anisotropic Elastic Materials
P. Chadwick,George Davey Smith +1 more
TL;DR: In this paper, it was shown that a free surface wave is intrinsically a subsonic phenomenon and that the set of directions on a particular anisotropic elastic half-space in which such waves can travel is determined by the slowness surface of the material.
Journal ArticleDOI
An image force theorem for dislocations in anisotropic bicrystals
David M. Barnett,Jens Lothe +1 more
TL;DR: In this paper, a simple image force theorem for a dislocated anisotropic bicrystal is derived using a formalism developed by Stroh (1962), and a formula is developed which allows one to obtain the prelogarithmic energy factor by simple numerical integration.
Journal ArticleDOI
Free surface (Rayleigh) waves in anisotropic elastic half-spaces: the surface impedance method
David M. Barnett,Jens Lothe +1 more
TL;DR: In this article, the existence of free surface waves in anisotropic linear elastic half-spaces has been investigated by appealing to the theory of uniformly moving dislocations, and an alternative framework relying on the surface impedance tensor is developed and fully exploited.
Journal ArticleDOI
On the existence of surface‐wave solutions for anisotropic elastic half‐spaces with free surface
Jens Lothe,David M. Barnett +1 more
TL;DR: In this article, it was shown that for a given direction of propagation on the free surface of a half-infinite anisotropic crystal, a surface wave solution with a certain phase velocity vR
References
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Journal ArticleDOI
Explicit Expressions for Dislocation Derivatives
K. Malen,Jens Lothe +1 more
TL;DR: In this paper, the velocity derivatives for uniformly moving dislocations are known to be related to such quantities as kinetic energy or mass, and the angular derivatives can be used for the calculation of the elastic field from a curved dislocation loop.
Journal ArticleDOI
Elastic surface waves in anisotropic crystals: a simplified method for calculating Rayleigh velocities using dislocation theory
TL;DR: In this article, a simplified method for determining the Rayleigh velocity of surface waves in arbitrarily anisotropic crystals is developed, which is the velocity at which the smaller of the eigenvalues of a certain 2*2 real symmetric matrix vanishes.
Journal ArticleDOI
Some Unifying Relations for Moving Dislocations
R. J. Beltz,T. L. Davis,K. Malén +2 more
TL;DR: In this article, the Lagrangian factor was used to extend Lothe's representation of the energy flow along a moving straight dislocation and to show the relationship between the mass, the back stress in acceleration, and the energy radiation from an oscillating straight dislocation.
Journal ArticleDOI
Dislocations at and near Planar Interfaces
J. Brækhus,Jens Lothe +1 more
TL;DR: In this article, it is shown that the energy factor for a dislocation at the interface can be expressed simply in terms of the K-matrices for the two anisotropic media.
Related Papers (5)
Foundations of the Theory of Surface Waves in Anisotropic Elastic Materials
P. Chadwick,George Davey Smith +1 more
On the existence of surface‐wave solutions for anisotropic elastic half‐spaces with free surface
Jens Lothe,David M. Barnett +1 more
Free surface (Rayleigh) waves in anisotropic elastic half-spaces: the surface impedance method
David M. Barnett,Jens Lothe +1 more