Structure and Properties of NbMoCrTiAl High-Entropy Alloy Coatings Formed by Plasma-Assisted Vacuum Arc Deposition

Abstract

The paper analyzes the structure and properties of metal, cermet, and ceramic NbMoCrTiAl high-entropy alloy (HEA) coatings formed on solid substrates by plasma-assisted vacuum arc deposition (from multicomponent gas-metal plasma through Nb, Mo, Cr, and TiAl cathode evaporation in argon and/or a mixture of argon and nitrogen). The analysis shows that all coatings represent a nanocrystalline (3–5 nm) multilayer film. The metal coating has a bcc lattice (a = 0.3146 nm). The ceramic coating has an fcc lattice (an uncertain lattice parameter due to highly smeared diffraction peaks). The coating hardness increases in the order of metal, cermet, and then ceramic, reaching 43 GPa at Young’s modulus equal to 326 GPa. When heated in air, the metal and cermet coatings start to oxidize at 630–640 °C, and the ceramic coating at 770–780 °C.

Analysis and Optimization of Contact Material Ablation under the Cumulative Effect of the Number of Breakings of OLTC

“…The simulation model employs the method of adding heat flux density to the anode contact surface to simulate the continuous heating process of the arc on the anode contact in the vacuum interrupter chamber [ 17 , 18 , 19 , 20 ]. The mathematical expression for the heat flux density is as follows: …”

CoxCrFeNiTi High-Entropy Alloys Prepared via Mechanical Alloying and Spark Plasma Sintering for Magnetron Sputtering Coatings

“…In addition to HEAs' elemental compositions and the chosen processing route, the deposition technique also influences the properties of the final coatings. In recent experiments involving HEA synthesized coatings, the most used deposition technologies include electrodeposition, magnetron sputtering, electrochemical vapour deposition, laser cladding, arc coating, thermal spraying, and plasma transfer arc coating [11][12][13][14]. Among these methods, magnetron sputtering offers some advantages for deposition of HEA coatings in form of thin films due to its precise control over film chemistry, microstructure, and physical and mechanical properties [15].…”