Multi-component low and high entropy metallic coatings synthesized by pulsed magnetron sputtering

This paper presents the findings of the synthesis of multicomponent (Al, W, Ni, Ti, Nb) alloy coatings from mosaic targets. For the study, a pulsed magnetron sputtering method was employed under different plasma generation conditions: modulation frequency (10 Hz and 1000 Hz), and power (600 W and 1000 W). The processes achieved two types of alloy coatings, high entropy and classical alloys. After the deposition processes, scanning electron microscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy techniques were employed to find the morphology, thickness, and chemical and phase compositions of the coatings. Nanohardness and its related parameters, namely H3.Er2, H.E, and 1.Er2H ratios, were measured. An annealing treatment was performed to estimate the stability range for the selected coatings. The results indicated the formation of as-deposited coatings exhibiting an amorphous structure as a single-phase solid solution. The process parameters had an influence on the resulting morphology-a dense and homogenous as well as a columnar morphology, was obtained. The study compared the properties of high-entropy alloy (HEA) coatings and classical alloy coatings concerning their structure and chemical and phase composition. It was found that the change of frequency modulation and the post-annealing process contributed to the increase in the hardness of the material in the case of HEA coatings

High-mass metal ion irradiation enables growth of high-entropy sublattice nitride thin films from elemental targets

Synthesis of high-entropy sublattice nitride (HESN) coatings by magnetron sputtering is typically done using custom-made alloyed targets with specific elemental compositions. This approach is expensive, requires long delivery times, and offers very limited flexibility to adjust the film composition. Here, we demonstrate a new method to grow HESN films, which relies on elemental targets arranged in the multicathode configuration with substrates rotating during deposition. TiVNbMoWN films are grown at a temperature of similar to 520(degrees)C using Ti, V, Nb, and Mo targets operating in the direct current magnetron sputtering mode, while the W target, operated by high power impulse magnetron sputtering (HiPIMS), provides a source of heavy ions. The energy of the metal ions EW+ is controlled in the range from 80 to 620 eV by varying the amplitude of the substrate bias pulses V-s, synchronized with the metal-ion-rich phase of HiPIMS pulses. We demonstrate that W(+ )irradiation provides dynamic recoil mixing of the film-forming components in the near-surface atomic layers. For EW+ >= 320 eV the multilayer formation phenomena, inherent for this deposition geometry, are suppressed and, hence, compositionally uniform HESN films are obtained, as confirmed by the microstructural and elemental analysis.(c) 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license(http://creativecommons.org/licenses/by/4.0/

High-mass metal ion irradiation enables growth of high-entropy sublattice nitride thin films from elemental targets

Synthesis of high-entropy sublattice nitride (HESN) coatings by magnetron sputtering is typically done using custom-made alloyed targets with specific elemental compositions. This approach is expensive, requires long delivery times, and offers very limited flexibility to adjust the film composition. Here, we demonstrate a new method to grow HESN films, which relies on elemental targets arranged in the multicathode configuration with substrates rotating during deposition. TiVNbMoWN films are grown at a temperature of similar to 520(degrees)C using Ti, V, Nb, and Mo targets operating in the direct current magnetron sputtering mode, while the W target, operated by high power impulse magnetron sputtering (HiPIMS), provides a source of heavy ions. The energy of the metal ions EW+ is controlled in the range from 80 to 620 eV by varying the amplitude of the substrate bias pulses V-s, synchronized with the metal-ion-rich phase of HiPIMS pulses. We demonstrate that W(+ )irradiation provides dynamic recoil mixing of the film-forming components in the near-surface atomic layers. For EW+ >= 320 eV the multilayer formation phenomena, inherent for this deposition geometry, are suppressed and, hence, compositionally uniform HESN films are obtained, as confirmed by the microstructural and elemental analysis.(c) 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license(http://creativecommons.org/licenses/by/4.0/

Carbon ion self-sputtering attained by sublimation of hot graphite target and controlled by pulse injection of a neon-helium gas mixture

The operation of graphite targets with an increased temperature (HT - hot target) is studied for the case of gas injection magnetron sputtering (GIMS) of: 1) diamond-like carbon (DLC), and 2) carbon-silicon carbide (C-SiC) films. A purposely-thinned graphite target with a reduced thermal conductivity is applied for DLC deposition, extending its high temperature sputtering range up to 1636 degrees C. For the purpose of C-SiC synthesis four sockets with a silicon carbide powder are designed within graphite target. In this approach, the C-SiC target surface can be heated up to 1443 degrees C due to a greater energy input from impulse plasma, in the range 322-932 J. The HT sputtering is energy-controlled by a pulsed injection of a neon-helium gas mixture. High-energy Ne+ and He+ ions extend the length of pulsed GIMS discharge due to the self-sputtering effect observed during the deposition of DLC and C-SiC films. These conditions result in an almost 5-fold increase in the film growth rate (up to 185 nm/min) with respect to the operation with a cold target, which is due to the assisting vapour sublimation from custom-designed graphite-based targets. The temperature boosted HT GIMS discharge, proves to be an efficient tool for reaching relatively high (similar to 35 %) sp(3)-hybridized C content in both carbon-based materials. It also allows for tailoring the energy bandgap of DLC-based optical structure, in the range from 1.7 to 2.75 eV, due to the formation of the (C-C) and (C-O) bonds. Higher content of silicon oxide (SiO2-x) and silicon carbide (SiC) phases (15 - 23 %) in the case of C-SiC films results in hardness increase from 21.8 to 30.1 GPa.Funding Agencies|National Science Centre of Poland [2018/31/B/ST8/00635]; National Science Centre of Poland under PRELUDIUM project [2017/27/N/ST8/00454]; Warsaw University of Technology within the Excellence Initiative: Research University [1820/151/Z09/2021]; Swedish Research Council VR [2018-03957]; Swedish Energy Agency [51201-1]</p