Abstract

The initial oxidation process of refractory alloy ceramics is closely related to their intrinsic properties such as surface adsorption or diffusion of oxygen atoms. We devise a machine learning model that predicts the full spectrum of adsorption energies for an oxygen atom on HfC1−xNx ceramic surfaces with quantum accuracy. With this approach, we show that the chemical complexity of carbonitride makes HfC1−xNx ceramics exhibit multiple types of adsorption sites with competing oxygen adsorption energies, leading to fewer preferable adsorption sites. In particular, we find that heavily doped N can change the stable adsorption site from the 3-fold hollow between metals and C atoms (MMC) to the top of Hf atoms (top-Hf), and the total number of preferable adsorption sites is regulated by their competing energies. In this scenario, we predict HfC0.76N0.24 has superior anti-oxidation performance, consistent with existing experimental measurements. Our findings can stimulate new strategies to enhance the oxidation resistance of refractory alloy ceramics.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.