Degradation mechanisms of Si/Nb/Zr/NbZr-modified TiCN coatings under 200 keV He+ ion irradiation: surface morphology and defect structure
Journal of Materials Science, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Basım Tarihi: 2026
- Doi Numarası: 10.1007/s10853-026-14029-4
- Dergi Adı: Journal of Materials Science
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Applied Science & Technology Source, Chemical Abstracts Core, Chimica, Compendex, INSPEC, MEDLINE, Public Affairs Index, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO), Materials Science & Engineering Collection (ProQuest), Technology Collection (ProQuest)
- Ankara Yıldırım Beyazıt Üniversitesi Adresli: Evet
Özet
Transition-metal carbonitride coatings are candidate barrier materials for components subjected to helium generation in advanced fission and fusion systems, yet the role of cation chemistry in setting their radiation tolerance remains poorly defined. Four TiMCN coatings (M = Si, Nb, Zr, NbZr), approximately 3 µm thick and deposited on Ti–6Al–4V by cathodic arc deposition, were irradiated with 200 keV He+ ions at fluences of 1.0 × 1013–1.0 × 1016 ions/cm2. Surface and microstructural evolution was followed by scanning and transmission electron microscopy and by white-light interferometry, and pit diameter, pit depth, and the depth-to-diameter ratio were evaluated in a two-way analysis of variance with composition and fluence as factors. Depth distributions of the implanted helium and the associated displacement damage were obtained from SRIM-2013, while the electron momentum densities of cation monovacancies and cation–anion divacancies containing up to four helium atoms were computed within a two-component density functional scheme. Composition, fluence, and their interaction were significant for all three descriptors (p < 0.05), so no common dose–response law applies across the series; the niobium-bearing compositions limited defect growth most effectively and the zirconium coating least. The implanted helium remains confined to the outer 0.7 µm of the layer at subpercent concentrations and sub-dpa damage levels, an order of magnitude in fluence below the blistering threshold reported for comparable nitride coatings. The calculated momentum distributions link this composition dependence to the type, size, and helium occupancy of the trapping defect.