A diffusion, oxidation reaction and large viscoelastic deformation coupled model with applications to SiC fiber oxidation

A chemo‐mechanical coupled constitutive model applied to the oxidation simulation of SiC/SiC composite

“…Furthermore, the introduction of the diffusion parameter prohibits the entrance of O 2 molecules into the fibers, which not only satisfies the real physical processes but also realizes the automatic capture of the reaction interface during the calculation process. It is assumed that the SiC material oxidation reaction rate linearly depends upon the concentration of the reactant 25 : $$\begin{equation}{\xi _f} = {R_f}{c_{{O_2}}}{c_{SiC}}\end{equation}$$where $${\xi _f}$$ is the reinforcement material oxidation rate, and R f is the oxidation reaction rate constant of the reinforcement material, which satisfies the Arrhenius equation: $$\begin{equation} {R_f} = {R_{f0}}\exp \left(\frac{{ - {Q_{f\xi }}}}{{RT}}\right)\end{equation}$$where $${R_{f0}},{Q_{f\varsigma }}$$ are the pre‐exponential coefficient and activation energy of the reinforcement material oxidation reaction, respectively. The mass conservation equations of O 2 molecules and SiC in the reinforcement elements are: $$\begin{equation}\frac{{\partial {C_{{O_2}}}}}{{\partial t}} = - \nabla \cdot {{\bm j}_{{O_2}}} - \frac{3}{2}{\xi _f}\end{equation}$$ $$\begin{equation}\frac{{\partial {C_{SiC}}}}{{\partial t}} = - {\xi _f}\end{equation}$$…”

“…Furthermore, the introduction of the diffusion parameter prohibits the entrance of O 2 molecules into the fibers, which not only satisfies the real physical processes but also realizes the automatic capture of the reaction interface during the calculation process. It is assumed that the SiC material oxidation reaction rate linearly depends upon the concentration of the reactant 25 :…”

Large Dense Periodic Arrays of Vertically Aligned Sharp Silicon Nanocones

“…Considering that different SiNW arrays were presented, we suggest that rat-IBE combined with thermal oxidation can be applied to different nanowire structures for sharpening purposes. We also would like to mention that numerical modeling of the 3D growth of the t-SiO 2 may answer the question of whether there is a significant influence of the internal angle on the film growth, where recent models considering fully coupled chemo-mechanical interaction might prove beneficial [67,[74][75][76]. A correct model may facilitate the choice of a temperature where oxidation self-limits at the desired diameter, taking the initial pre-shaped SiNC top diameter as an input.…”

A continuum electro-chemo-mechanical gradient theory coupled with damage: Application to Li-metal filament growth in all-solid-state batteries

“…Currently, continuum electro-chemomechanics theories for energy storage materials in the literature have been largely developed for diffusion of a conserved species across the host (i.e. no chemical reactions) [67][68][69][70][71], with some recent efforts capturing diffusion-reaction in solids [72][73][74]. While rigorous, current diffusion-reaction-deformation frameworks do not consider transport of charged species across the host in the presence of electric field, and thus are limited to modeling chemical rather than electro-chemical reactions.…”