A low-temperature prismatic slip instability in Mg understood using machine learning potentials

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{
  "revision": 2, 
  "id": "1614", 
  "created": "2023-01-16T17:40:13.656516+00:00", 
  "metadata": {
    "doi": "10.24435/materialscloud:3f-w3", 
    "status": "published", 
    "title": "A low-temperature prismatic slip instability in Mg understood using machine learning potentials", 
    "mcid": "2023.10", 
    "license_addendum": null, 
    "_files": [
      {
        "description": "Neural network potentials NNP63 and NNP77", 
        "key": "Potentials.zip", 
        "size": 267256, 
        "checksum": "md5:363d7d85af875592dee8df1d45ba2c62"
      }, 
      {
        "description": "Input files for lammps and vasp", 
        "key": "Code.zip", 
        "size": 95021, 
        "checksum": "md5:2dc31d8e27817ddd3b2d3d4ce580ff76"
      }
    ], 
    "owner": 875, 
    "_oai": {
      "id": "oai:materialscloud.org:1614"
    }, 
    "keywords": [
      "Magnesium", 
      "Prismatic slip", 
      "Neural Network potential", 
      "Minimum energy path", 
      "MARVEL"
    ], 
    "conceptrecid": "1613", 
    "is_last": true, 
    "references": [
      {
        "type": "Journal reference", 
        "doi": "10.1016/j.actamat.2022.118490", 
        "citation": "X. Liu, M. RahbarNiazi, T. Liu, B. Yin, W.A. Curtin, Acta Materialia 243, 118490 (2023)"
      }
    ], 
    "publication_date": "Jan 17, 2023, 10:48:54", 
    "license": "Creative Commons Attribution 4.0 International", 
    "id": "1614", 
    "description": "Prismatic slip in magnesium at temperatures T \u2272 150 K occurs at \u223c 100 MPa independent of temperature, and jerky flow due to large prismatic dislocation glide distances is observed; this athermal regime is not understood. In contrast, the behavior at T \u2273 150 K is understood to be governed by a thermally-activated double-cross-slip of the stable basal screw dislocation through an unstable or weakly metastable prism screw configuration and back to the basal screw. Here, a range of neural network potentials (NNPs) that are very similar for many properties of Mg including the basal-prism-basal cross-slip path and pro- cess, are shown to have an instability in prism slip at a potential-dependent critical stress. One NNP, NNP-77, has a critical instability stress in good agreement with experiments and also has basal-prism-basal transition path energies in very good agreement with DFT results, making it an excellent potential for understanding Mg prism slip. Full 3d simulations of the expansion of a prismatic loop using NNP-77 then also show a transition from cross-slip onto the basal plane at low stresses to prismatic loop expansion with no cross- slip at higher stresses, consistent with in-situ TEM observations. These results reveal (i) the origin and prediction of the observed unstable low-T prismatic slip in Mg and (ii) the critical use of machine-learning potentials to guide discovery and understanding of new important metallurgical behavior.", 
    "version": 1, 
    "contributors": [
      {
        "email": "xin.liu@epfl.ch", 
        "affiliations": [
          "Laboratory for Multiscale Mechanics Modeling, \u00c9cole Polytechnique F\u00e9d\u00e9rale de Lausanne, 1015 Lausanne, Switzerland"
        ], 
        "familyname": "Liu", 
        "givennames": "Xin"
      }, 
      {
        "affiliations": [
          "Laboratory for Multiscale Mechanics Modeling, \u00c9cole Polytechnique F\u00e9d\u00e9rale de Lausanne, 1015 Lausanne, Switzerland"
        ], 
        "familyname": "Rahbar Niazi", 
        "givennames": "Masoud"
      }, 
      {
        "affiliations": [
          "Institute of Applied Mechanics and Center for X-Mechanics, Zhejiang University, 310027 Hangzhou, China"
        ], 
        "familyname": "Liu", 
        "givennames": "Tao"
      }, 
      {
        "affiliations": [
          "Institute of Applied Mechanics and Center for X-Mechanics, Zhejiang University, 310027 Hangzhou, China"
        ], 
        "familyname": "Yin", 
        "givennames": "Binglun"
      }, 
      {
        "affiliations": [
          "Laboratory for Multiscale Mechanics Modeling, \u00c9cole Polytechnique F\u00e9d\u00e9rale de Lausanne, 1015 Lausanne, Switzerland"
        ], 
        "familyname": "Curtin", 
        "givennames": "William"
      }
    ], 
    "edited_by": 576
  }, 
  "updated": "2023-01-17T09:48:54.324878+00:00"
}