A new model-based creep equation for dispersion strengthened materials
Joachim Rösler,Eduard Arzt +1 more
TLDR
In this paper, a new creep equation is developed which considers as the rate-controlling event the thermally activated detachment of dislocations from dispersoid particles exerting an attractive force.Abstract:
The strongly stress-sensitive and temperature-dependent creep behaviour of dispersion strengthened materials cannot be described satisfactorily by current creep laws. In this paper a new creep equation is developed which considers as the rate-controlling event the thermally activated detachment of dislocations from dispersoid particles exerting an attractive force. The approach is motivated by recent TEM observations and theoretical calculations which strongly suggest that the “classical” view, according to which particles merely force dislocations to climb around them, is inadequate. The creep equation is applied to a dispersion-strengthened superalloy, two aluminium alloys and bubble-strengthened tungsten. Practical conclusions, regarding the optimum dispersoid size and alloy development, are drawn.read more
Citations
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References
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Book
Dislocations in solids
TL;DR: In this article, Bertotti, Ferro, and Mazetti proposed a theory of dislocation drag in covalent crystals and formed a model of the formation and evolution of dislocations during irradiation.
Journal ArticleDOI
Theory of Steady‐State Creep Based on Dislocation Climb
TL;DR: In this article, a theory of steady-state creep is developed using Mott's mechanism of dislocation climb, which is assumed in the analysis that the rate-controlling process is the diffusion of vacancies between dislocations which are creating vacancies and those which are destroying them.
Journal ArticleDOI
Threshold stresses for dislocation climb over hard particles: The effect of an attractive interaction
Eduard Arzt,David Wilkinson +1 more
TL;DR: In this paper, the authors present a model for the effect of an attractive interaction between dislocations and hard spherical particles on the process of dislocation bypass by local climb, treating the interaction by assigning a line tension to the dislocation which is lower in the vicinity of the particle than in the matrix.
Journal ArticleDOI
The kinetics of dislocation climb over hard particles—II. Effects of an attractive particle-dislocation interaction
Eduard Arzt,Joachim Rösler +1 more
TL;DR: In this paper, a model for the high-temperature creep strength of dispersion strengthened materials is presented based on part I of this paper which treated dislocation climb over non-interacting particles.
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