A comparative DFT study on physical properties of metal-substituted niobium carbide

ÇATIKKAŞ B., AYDIN S.

Physica B: Condensed Matter, cilt.716, 2025 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 716
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1016/j.physb.2025.417748
  • Dergi Adı: Physica B: Condensed Matter
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Chemical Abstracts Core, Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
  • Anahtar Kelimeler: Hardness, Mechanical properties, Niobium carbide, Transition metal carbides
  • Gazi Üniversitesi Adresli: Evet

Özet

The structural and mechanical properties, and the stability characteristics of the metal-substituted niobium carbides (Nb3MC4) have been investigated by using density functional first-principles calculations. The effect of metal on fcc-niobium carbide (NbC) properties is discussed comparatively. Among the compounds, only Nb3MC4 (M = Sc, Ti, Zr, Hf, and Ta) compounds are dynamically stable, and the stability of NbC including the different calculation scheme is presented. The metal substitution makes the structure more thermodynamically stable for M = Sc, Ti, Zr, and Hf compounds than NbC. The bonding of the metal-substituted niobium carbides is a mixture of covalent, ionic, and metallic components. The mechanical parameters such as bulk, shear, and Young's moduli, the tetragonal shear modulus, Pugh's ratio, Cauchy pressure, Kleinman parameter, and machinability index are evaluated. The hardnesses of the compounds are calculated by different models including metallicity and machine learning predictor. A comprehensive and comparative study of the metal-substituted stable niobium carbides is presented.