Deciphering the mechanical strengthening mechanism: soft metal doping in ceramic matrices - a case study of TiN-Ag films

Luan, Jing (author), Kong, Fanlin (author), Xu, Junhua (author), Fernandes, Filipe Daniel (author), Evaristo, Manuel (author), Dong, Songtao (author), Cavaleiro, Albano (author), Ju, Hongbo (author)

Soft metals have been widely added into ceramic-based films for fully meeting the demanding requirements of green tribological applications. However, the resulting considerable increase of the mechanical strength by adding a soft metal below 5 at.%, which reversed the rule-of-mixture, was still not fully revealed. In this paper, a case study of TiN-Ag films was carried out to investigate the strengthening mechanism induced by adding soft metal in TiN-Ag composite/multilayered films deposited by magnetron sputtering. The results showed that dual-phases of fcc-TiN and fcc-Ag co-existed in the composite films with the Ag particles embedded in the matrix. In some areas of the Ag particles, with a size below 4 nm, epitaxial growth with the TiN template was detected, which obliged the lattice to be distorted and shrunken. Consequently, both hardness and elastic modulus were enhanced from 21 and 236 GPa, for the reference TiN film, to 26 and 323 GPa for the TiN-Ag composite film with 2.4 at.% Ag. The possibility of having the epitaxial growth of Ag within TiN were also confirmed by designing a TiN/Ag multilayered film with an Ag layer thickness of ∼3 nm.

• Language: English
• Keywords: magnetron sputtering, soft metal, ceramic-based films, epitaxy structure, strengthening mechanism
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2024
• Number of pages: 6 str.
• Numbering: Vol. 248, art. 113489
• PID: 20.500.12556/RUL-180478
• UDC: 621.89:669.018.26
• ISSN on article: 0264-1275
• DOI: 10.1016/j.matdes.2024.113489
• COBISS.SI-ID: 271107843
• Publication date in RUL: 10.03.2026

Record is a part of a journal

• Title: Materials & design
• Shortened title: Mater. des.
• Publisher: Scientific and Technical Press
• ISSN: 0264-1275
• COBISS.SI-ID: 10626075

Licences

• License: CC BY-NC 4.0, Creative Commons Attribution-NonCommercial 4.0 International
• Link: http://creativecommons.org/licenses/by-nc/4.0/
• Description: A creative commons license that bans commercial use, but the users don’t have to license their derivative works on the same terms.

Secondary language

• Language: Slovenian
• Keywords: magnetronsko razprševanje, mehke kovine, epitaksijska struktura, mehanizem utrjevanja