Аннотации:
Рассмотрено моделирование кинетики вакансий при термомеханическом нагружении, которое включает циклические напряжения растяжения
и воздействие температуры. Кинетика вакансий определяется диффузионным уравнением с учетом диффузионных и термических напряжений. По-
лучена система уравнений для неоднородной концентрации вакансий для
одномерной задачи, решаемая численными методами. The evolution of vacancy system and pore emergence under the influence of cyclic thermomechanical
loading determines the durability of the nanocrystalline two-phase alloys such as
superalloys, which are composite materials. The emergence of excess non-equilibrium vacancies, the
activation of diffusion processes and the pore growth occur under the influence of thermo-mechanical
loading. However, kinetics of the emergence and evolution of the excess vacancy concentration at
various kinds of thermo-mechanical loading arising during the operation process have not been
investigated yet. In this paper, the vacancy concentration in the one-dimensional model for thermomechanical
loading including cyclic tensile stresses, thermal stresses and heating to high temperature
taking into account microstructure is calculated. The considerable supersaturation of non-equilibrium
vacancies arises in nanostructured alloys under the influence of thermo-mechanical loading. The rising
of diffusion may occur at a critical value of excess vacancies as part of the diffusion-deformation
stability mechanism, when small local fluctuation of excess vacancy concentration begins to grow. The
growth occurs due to a Gibbs energy decrease in the increased vacancy concentration caused by the
influence of thermo-mechanical stresses.
Описание:
А.В. Галактионова, А.К. Емалетдинов
Уфимский государственный авиационный технический университет, г. Уфа,
Российская Федерация
E-mail: g-arina@yandex.ru. A.V. Galaktionova, A.K. Emaletdinov
Ufa State Aviation Technical University, Ufa, Russian Federation
E-mail: g-arina@yandex.ru