English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

A continuum theory based on thermodynamics has been developed for modelingdiffusional creep of polycrystalline solids. It consists of a coupled problemof vacancy diffusion and mechanics where the vacancy generation/absorption atgrain boundaries is driven by grain boundary dislocations climb. The model isstated in terms of general balance laws and completed by the choice ofconstitutive equations consistent with classical non-equilibriumthermodynamics. The kinetics of diffusional creep is derived fromphysically-based mechanisms of climb of dislocations at grain boundaries, thusintroducing a dependence of diffusional creep on the density and mobility ofboundary dislocations. Several representative examples have been solved usingthe finite element method and assuming representative volume elements made upof an array of regular-shaped crystals. The effect of stress, temperature,grain size, and grain boundary dislocation mobility is analyzed and comparedwith classical theories of diffusional creep. The simulation resultsdemonstrate the ability of the present model to reproduce the macroscopicstress and grain size dependence observed under both diffusion and interfacecontrolled regimes as well the evolution of this dependency with thetemperature. In addition, the numerical implementation of the model allows topredict the evolution of microscopic fields through the microstructure.

A coupled model of diffusional creep of polycrystalline solids based on climb of dislocations at grain boundaries