Anomalous diffusion along metal/ceramic interfaces.

ABSTRACT: Interface diffusion along a metal/ceramic interface present in numerous energy and electronic devices can critically affect their performance and stability. Hole formation in a polycrystalline Ni film on an ?-Al2O3 substrate coupled with a continuum diffusion analysis demonstrates that Ni diffusion along the Ni/?-Al2O3 interface is surprisingly fast. Ab initio calculations demonstrate that both Ni vacancy formation and migration energies at the coherent Ni/?-Al2O3 interface are much smaller than in bulk Ni, suggesting that the activation energy for diffusion along coherent Ni/?-Al2O3 interfaces is comparable to that along (incoherent/high angle) grain boundaries. Based on these results, we develop a simple model for diffusion along metal/ceramic interfaces, apply it to a wide range of metal/ceramic systems and validate it with several ab initio calculations. These results suggest that fast metal diffusion along metal/ceramic interfaces should be common, but is not universal.

SUBMITTER: Kumar A 

PROVIDER: S-EPMC6286315 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature