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/

Global: Zendy Plus annual

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

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Creep in single crystal Nickel-based superalloys has been a topic of interestsince decades, and nowadays simulations are more and more able to complementexperiments. In these alloys, the $\gamma/\gamma'$ phase microstructureco-evolves with the system of dislocations under load, and understanding themutual interactions is essential for understanding the resulting creepproperties. Predictive modeling thus requires multiphysics frameworks capableof modeling and simulating both the phase and defect microstructures. To do so,we formulate a coupled model of phase-field evolution and continuum dislocationdynamics which adequately accounts for both statistically stored andgeometrically necessary dislocations. The simulated $\gamma/\gamma'$ phasemicrostructure with four $\gamma'$ variants and co-evolving dislocationmicrostructure is found to be in good agreement with experimental observations.The creep strain curve is obtained as a natural by-product of themicrostructure evolution equations without the need for additional parameterfitting. We perform simulations of $\gamma/\gamma'$ evolution for differentdislocation densities and establish the driving forces for microstructureevolution by analyzing in detail the changes in different contributions to theelastic and chemical energy density. Together with comparisons betweensimulated and experimental creep curves this investigation reveals themechanisms controlling the process of directional coarsening (rafting) anddemonstrates that the kinetics of rafting significantly depends oncharacteristics of the dislocation microstructure. In addition to rafting underconstant load, we investigate the effect of changes in loading conditions andexplore the possibility of improving creep properties by pre-rafting along adifferent loading path.

A continuum approach to combined $\gamma/\gamma'$ evolution and dislocation plasticity in Nickel-based superalloys