Phase stability in the Hf-N and Zr-N systems

Li, Jonathan [Univ. of California, Santa Barbara, CA (United States)] (ORCID:0000000326320080); Ober, Derick [Univ. of California, Santa Barbara, CA (United States)] (ORCID:0000000170719406); Van der Ven, Anton [Univ. of California, Santa Barbara, CA (United States)]

doi:10.1103/physrevmaterials.8.123603

DOE OSTI · 2872738

Phase stability in the Hf-N and Zr-N systems

Li, Jonathan [Univ. of California, Santa Barbara, CA (United States)] (ORCID:0000000326320080)·Ober, Derick [Univ. of California, Santa Barbara, CA (United States)] (ORCID:0000000170719406)·Van der Ven, Anton [Univ. of California, Santa Barbara, CA (United States)]

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Abstract

Hf and Zr nitrides are promising compounds for many technologically important areas, including high-temperature structural applications, quantum computing, and solar and optical applications. Here, this article reports on a comprehensive first-principles statistical mechanics study of phase stability in the Hf-N and Zr-N binary systems. A high solubility of nitrogen in the hcp forms of Hf and Zr is predicted. The rocksalt forms of HfN and ZrN can also tolerate a high degree of off-stoichiometry through the introduction of nitrogen and metal vacancies. The Hf-N binary favors a family of stacking faulted parent crystal structures at intermediate nitrogen concentrations that host a unique form of short-range order among nitrogen interstitials and vacancies. These phases can accommodate some degree of configurational entropy and remain ordered to temperatures as high as 1200 K.

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Monte Carlo methods electronic structure first-principles calculations nitrides phase diagrams transition metals

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Li, Jonathan [Univ. of California, Santa Barbara, CA (United States)] (ORCID:0000000326320080), Ober, Derick [Univ. of California, Santa Barbara, CA (United States)] (ORCID:0000000170719406), Van der Ven, Anton [Univ. of California, Santa Barbara, CA (United States)]. 2024-12-06. Phase stability in the Hf-N and Zr-N systems. https://doi.org/10.1103/physrevmaterials.8.123603

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