High-entropy transition metal nitride thin films alloyed with Al: Microstructure, phase composition and mechanical properties

Materials & Design

L. Hultman¹  B. Bakhit²  A. Vasylenko³  P. Schweizer⁴  G. Greczynski⁵  A.V. Pshyk⁶  J. Michler⁷  T.E.J. Edwards⁷ 

[1] Corresponding author.;Empa — Swiss Federal Laboratories for Materials Testing and Research, Laboratory for Mechanics of Materials and Nanostructures, Thun CH-3602, Switzerland;Thin Film Physics Division, Department of Physics (IFM), Linkoping University, SE-581 83 Linkoping, Sweden;Department of Chemistry, University of Liverpool, Liverpool, United Kingdom;Empa — Swiss Federal Laboratories for Materials Testing and Research, Laboratory for Mechanics of Materials and Nanostructures, Thun CH-3602, Switzerland;NanoBioMedical Centre, Adam Mickiewicz University, Poznań, Poland;Thin Film Physics Division, Department of Physics (IFM), Linkoping University, SE-581 83 Linkoping, Sweden;

关键词: High-entropy nitride;    HiPIMS;    Mechanical properties;    Hardness;    Yield strength;   

DOI  :  

来源: DOAJ

【 摘 要 】

Deviation from equimolar composition in high-entropy multielement ceramics offers a possibility of fine-tuning the materials’ properties for targeted application. Here, we present a systematic experimental and theoretical study on the effects of alloying equimolar pentanary (TiHfNbVZr)N and hexanary (TiHfNbVZrTa)N high-entropy nitrides with Al. Although being predicted to be metastable by ab initio density-functional theory calculations, single-phase fcc NaCl-structured solid solution thin films with Al solubility limits as high as x ∼ 0.51–0.61 in (TiHfNbVZr)1-xAlxN and x ∼ 0.45–0.64 in (TiHfNbVZrTa)1-xAlxN are synthesised utilizing a hybrid deposition technique that offers dynamic mixing of film atoms from Al+ subplantation and non-equilibrium growth conditions leading to quenching of the desired film structure. In experimental studies supplemented with density-functional theory calculations, it is demonstrated that Al concentration in alloys with the multielement compositions of high-entropy nitride thin films determine hardness, yield strength, toughness, and ability to deform plastically up to fracture due to different deformation mechanisms arising from the electronic structure and phase compositions.

【 授权许可】

Unknown