Showing papers by "Oleg D. Sherby published in 1973"
TL;DR: In this paper, it was shown that under high stresses polycrystalline nonmetals obey the equation eασn, where e is the steady-state creep rate, σ the applied stress, and n a constant which is usually either 3 or 5.
Abstract: Published results on the high-temperature creep of polycrystalline nonmetals indicate that under high stresses many of them obey the equation eασn, where e is the steady-state creep rate, σ the applied stress, and n a constant which is usually either 3 or 5. A fifth-power stress dependence is observed in most pure metals; the creep rate is thought to be controlled by a slip creep process involving dislocation climb. Third-power dependence is not merely a combination of fifth-power-dependent slip creep and first-power-dependent Nabarro-Herring creep but appears to be controlled by a separate mechanism. This mechanism may be associated with Nabarro's dislocation climb model or with Weertman's microcreep model involving charged dislocations. It appears that the ratio of the anion radius to the cation radius is usually >2 in nonmetals for which n=3 and >2 in those for which n=5.
49 citations
TL;DR: In this article, an activation energy of 3 eV was obtained from the resistivity annealing studies, which is in good agreement with the presently accepted activation energy for vacancy migration in ψ-tungsten.
17 citations
TL;DR: In this paper, a plain carbon steel of eutectoid composition was treated with thermal mechanical treatments to improve the ductility and strength of the fine spheroidized structure.
17 citations
TL;DR: In this article, the high temperature mechanical properties of high purity α-, β- and γ-uranium were investigated by compression testing, from which steady state creep parameters were obtained.
11 citations