{
  "abstract": "Grain growth kinetics and grain-boundary (GB) properties in uranium mononitride (UN) are investigated through an integrated multiscale framework combining molecular dynamics (MD), phase-field modeling, and surrogate-assisted uncertainty quantification. MD simulations yield GB energies for 27 symmetric tilt boundaries from 0--2000~K, which are consistent with available DFT values. The average GB energy is nearly temperature-independent below 1000~K and increases at higher temperatures. A mechanistic pore-drag model applied to the only available grain growth dataset for actinide nitrides yields a mobility reduction factor of $s \\approx 0.93$--$0.99$, statistically indistinguishable from unity, confirming that pore drag is negligible under the experimental conditions. The intrinsic GB mobility is therefore extracted directly from the effective mobility, yielding $M_0 = 2.05\\times10^{-15}$~m$^4$/(J$\\cdot$s) and $Q_M = 0.89$~eV. Phase-field simulations conducted from 1500--2000~K confirm normal curvature-driven grain growth, with grain size distributions converging to the Hillert-like form. A surrogate-assisted global sensitivity analysis---combining principal component analysis, Gaussian process regression, and Sobol decomposition---reveals that the mobility prefactor $M_0$ dominates output variance at all times, followed by the activation energy $Q_M$, while the GB energy $γ$ contributes minimally. These results establish the first quantitative grain growth framework for UN and identify the reduction of uncertainty in $M_0$ and $Q_M$ as the highest-priority target for future experimental efforts.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.10977",
  "author_total": 5,
  "authors": [
    {
      "name": "Mohamed AbdulHameed"
    },
    {
      "name": "Fadel M. Nasr"
    },
    {
      "name": "Wen Jiang"
    },
    {
      "name": "Mahmoud Yaseen"
    },
    {
      "name": "Benjamin Beeler"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2rn53mqemrnp7.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.10977",
  "fulltext_url": null,
  "id": "2rn53mqemrnp7",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.10977",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "cond-mat.mtrl-sci"
    ],
    [
      "openalex",
      "2505|Nuclear Materials and Properties"
    ]
  ],
  "openalex": "W7212303016",
  "pdf_url": "https://arxiv.org/pdf/2609.10977",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-10",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2rn53mqemrnp7.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:20:26Z",
      "native_id": "2609.10977",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.10977"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "A model of grain growth in UN integrating molecular dynamics, phase-field modeling, and uncertainty quantification",
  "title_text": "A model of grain growth in UN integrating molecular dynamics, phase-field modeling, and uncertainty quantification",
  "type": "preprint",
  "updated_at": "2026-10-30T12:20:26Z",
  "url": "https://research.draconitic.com/paper/2rn53mqemrnp7",
  "venue": "arXiv",
  "versions": []
}