{
  "abstract": "Dissimilar Al/Cu joints are essential to battery-pack assemblies; however, their mechanical strength is limited by brittle Al-Cu intermetallic compounds (IMCs) such as Al2Cu and Al4Cu9. Interlayer strategies to suppress these phases remain largely empirical, lacking a predictive framework linking interlayer chemistry to the phases that form and to their intrinsic mechanical character. Here an Ag interlayer is introduced and combines computational thermodynamics, first-principles calculations, microstructural characterization, and mechanical testing into a single self-consistent description of the joint. CALculation of PHAse Diagrams (CALPHAD) equilibrium and Scheil simulations predict the solidification path of the Al-rich Al-Ag fusion zone and explain why Cu incorporation is limited when Ag is present; energy-dispersive X-ray spectroscopy (EDS) and electron backscatter diffraction (EBSD) confirm an FCC Al-Ag solid solution as the dominant constituent. First-principles phonon calculations within the quasiharmonic approximation yield finite-temperature entropy and Gibbs energy, benchmarked against CALPHAD, while elastic constants assess ductility via the Pugh criterion (i.e., the bulk/shear (B/G) modulus ratio). All Al-Ag phases, including the observed solid solution, exceed the Pugh threshold of 1.75, whereas the targeted Al-Cu IMCs do not, giving a mechanistic basis for the interlayer's effectiveness. This microstructural change translates into improved performance: nominal strength rises from 47.9 to 67.4 MPa. Nanoindentation gives a fusion-zone reduced modulus of 82.8 GPa (Young's modulus 82.0 GPa), versus a calculated 0 K Voigt-Reuss-Hill value of 71.4 GPa. The present work establishes a transferable CALPHAD, first-principles, and experiment workflow for rational interlayer selection in dissimilar-metal joining.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.09364",
  "author_total": 9,
  "authors": [
    {
      "name": "Shuang Lin"
    },
    {
      "name": "Kyubok Lee"
    },
    {
      "name": "Jiahui Ye"
    },
    {
      "name": "Ho Kwon"
    },
    {
      "name": "Shun-Li Shang"
    },
    {
      "name": "Allison M. Beesea"
    },
    {
      "name": "Xun Liu"
    },
    {
      "name": "Jingjing Li"
    },
    {
      "name": "Zi-Kui Liu"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/anfszeptxvkb3.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.09364",
  "fulltext_url": null,
  "id": "anfszeptxvkb3",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.09364",
  "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"
    ],
    [
      "arxiv",
      "physics.comp-ph"
    ],
    [
      "openalex",
      "2210|Advanced Welding Techniques Analysis"
    ]
  ],
  "openalex": "W7212125891",
  "pdf_url": "https://arxiv.org/pdf/2609.09364",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-08",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/anfszeptxvkb3.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:20:12Z",
      "native_id": "2609.09364",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.09364"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.comp-ph",
      "subfield": "computational"
    },
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Phase stability and mechanical response of Ag-interlayered Al/Cu resistance spot-welded joints",
  "title_text": "Phase stability and mechanical response of Ag-interlayered Al/Cu resistance spot-welded joints",
  "type": "preprint",
  "updated_at": "2026-10-30T12:20:12Z",
  "url": "https://research.draconitic.com/paper/anfszeptxvkb3",
  "venue": "arXiv",
  "versions": []
}