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Various boron contents of AlCrNbTiBN coatings were prepared by radiofrequency reactive magnetron cosputtering on both 304 stainless steel and 100 silicon substrates. Boron-doped AlCrNbTiN coatings resulted in a dense structure and a decrease in the grain size. As compared to boron-free coatings, the hardness of AlCrNbTiBN coatings increased from 25.8 to 31.1 GPa at a boron content of 3.3 at. %. The AlCrNbTiBN coatings exhibited favorable hardness due to the increased dense structure, defect density, grain refinement, and solid solution strengthening. The wear test at 700 °C showed that coatings without boron reveal three times the wear rate than those coatings doped with boron. In this study, the multicomponent (AlCrNbTiBN) coating demonstrated favorable mechanical and tribological properties. This implies that AlCrNbTiBN coatings might provide promising applicability in the wear-resistant field at high temperatures. Furthermore, boron-doped multicomponent nitride coating appears to enhance coating’s mechanical properties and wear resistance, indicating potential development in the near future.

This study aims at investigating the potential application of plasma-activated soy waste solution in plasma agriculture-related fields. The pH value, conductivity, and nitrate concentration as a function of treating time and post-treatment time are presented. The results show that argon plasma could react with soy waste solution and enhance the nitrate concentration, which is considered beneficial for plant growth. Moreover, a small increase in acidity makes the treated solution more suitable for plant growth, which is another advantage of the plasma-activated soy waste solution. In short, plasma-activated soy waste solution could be a potential candidate for additional nitrate-enhanced sources in organic fertilizer due to its eco-friendly and low-cost characteristics.

The high entropy nitride coatings (Cr0.35Al0.25Nb0.12Si0.08V0.20)Nx with different nitrogen concentrations were fabricated via varying the N2/(Ar + N2) ratio in a RF magnetron reactive sputtering system. The effect of the N2/(Ar + N2) ratio on the crystal structure, chemical composition variation, deposition rate, residual stress, and hardness were investigated in details and revealed in this work. The crystal structure of the metallic coating was amorphous, while the nitride coating exhibited the B1–NaCl structure as the nitrogen concentration of coating exceeded 43 at%. The residual stress was compressive in all coatings, ranging from −0.95 GPa to −3.61 GPa. As the coating nitrogen concentration reached 50 at%, the maximum hardness of this high entropy nitride coating was around 35 GPa and the appealing H/E and H3/E2 value of 0.12 and 0.52, respectively, was also revealed. Finally, a new indicator “composition variation degree” was proposed and employed in this study. This indicator provided a rather effective usage as it could reduce the complexity of defining the composition difference between the deposited coating and the designed value in a multi-component system, especially when the coating nitrogen concentration was varied.

In recent years, high entropy alloy (HEA) nitrides have shown outstanding properties in the field of protective hard coatings. However, for monolayer HEA nitride thin film, low adhesion strength and high residual stress lead to poor anti-wearing capabilities. This study aims at investigating the effect of metallic layer thickness in superelastic Ni51.3Ti48.7 on adhesion strength and wear resistance of HEA (Cr0.35Al0.25Nb0.12Si0.08V0.20) nitride coating. The results showed that the high compressive residual stress of top nitride layer was relieved by introducing NiTi metallic layer. The adhesion strength, wear track morphology and surface fracture were associated with the metallic layer thickness. Adding a proper thickness of NiTi metallic layer can improve the wear resistance of HEA nitride coating. Nevertheless, it was also observed that if the metallic layer thickness was not well controlled, the wear resistance enhancement was insignificant. The findings of this study are suggestive to provide a feasible approach for fabricating anti-wearing HEA nitride coatings.

High entropy alloy nitride coatings (HEAN), showing superior mechanical strength, high oxidation resistance, and thermal stability, have often been used in protective hard coatings field. However, the high temperature tribological field of novel HEA nitride films has not yet been well studied. The correlations among tribological properties, compressive residual stress, mechanical properties, and self-lubricating oxide are still limited. In this research, the novel (AlCrNbSiTiMo)N coatings were fabricated on both Inconel-718 and Si (100) substrate by radio frequency (RF) magnetron sputtering via tuning both substrate bias at 300 °C deposition temperature. The (AlCrNbSiTiMo)N coatings with a specific substrate bias exhibit an outstanding hardness of 34.5±0.8 GPa. In the wear test at 700 °C, the films deposited at −100 V revealed the lowest wear rate around 1.2 × 10−6 mm3N−1 m−1. With Molybdenum doping, the MoO3 Magneli phase was observed on the surface at elevated temperature wearing process, and the friction coefficient at high temperature decreased significantly due to a lubricating surface. The coating exhibited the average friction coefficient value of 0.48 in the wear test of 700 °C. The high temperature tribological performance was addressed and related to the mechanical properties, the plastic deformation resistance H3/E2, and the excess residual stress of the films. This study provides a new design for hard coatings applied to severe wearing conditions. By tuning substrate bias, the (AlCrNbSiTiMo)N coatings exhibit outstanding mechanical and tribological characteristics, which will be a promising candidate for high temperature tribological protective film.

This study aimed to investigate the influence of oxygen flow rate on magnetic and high-frequency properties of as-deposited FeHfO thin films, which were fabricated by DC reactive magnetron sputtering in an Ar + O2 atmosphere. These films exhibited mixed phases of α-Fe nanograins and amorphous HfO2 phase, showing nanocrystalline structure and soft magnetic properties. The dispersion character of FeHfO films changed from relaxation-type to resonance-type when the oxygen flow rate varied from 1.0 to 1.2 sccm. Furthermore, the Fe58.8Hf13.1O28.1 film with the optimum O2 flow rate of 1.2 sccm exhibited high saturation magnetization of 10.6 kG, a high resistivity of 258 µΩ cm, a real component of permeability (µ′) of 250 up to 1 GHz and a high ferromagnetic resonance frequency of 2.5 GHz. It is expected that this film should be promising for practical applications as a high-frequency ferromagnetic material.

Effects of the Hf content in Co–Hf–Ta thin films on the microstructure and magnetic properties were investigated in this study. It was found that appropriate Hf addition can effectively refine the Co grain size. Co grain sizes sharply decreased from 50 nm down to 2.3 nm with increasing the Hf content from 1.02 at.% to 2.81 at.%, leading to the reduced magneto-crystalline anisotropy. The Co–Hf–Ta thin films with small Co grains reveal low anisotropy field, low coercivity, and high resistivity. By optimizing the Hf content, the film with Hf concentration of 2.81 at.% exhibits excellent soft magnetic properties: high saturation magnetization (4 πM S ∼ 13.6 kG), and low coercivity ( H C ∼ 0.6 Oe). The effective permeability of the film reaches 800 and remains constant up to 1 GHz.

SrCaSiAl2O7:xEu2+ (x = 0.00—0.05) phosphors are synthesized by solid state reaction of stoichiometric mixtures of SrCO3, CaCO3, Al2O3, and Eu2O3 using an excess of 6 wt.% H3BO3 as a flux (alumina crucible, 15%H2/N2, 1573 K, 8 h).

The crystal structure of a Eu2+-activated SrCaSiAl2O7 phosphor was refined and determined as a tetragonal structure with the refinement converged to Rp = 7.05%, Rwp = 10.67%, and χ2 = 2.637 by Rietveld refinement using a synchrotron light source. By doping different contents of Eu2+, the emission peaks gives a range between 526 nm and 535 nm. The estimated Stokes shifts and Commission International de l’Eclairage (CIE) chromaticity coordinates are 16576–16896 cm−1 and (0.3155, 0.5073) to (0.3685, 0.5284), respectively. By tuning the ratio of phosphors and silicone, the optical properties of the three-band white LEDs could be tuned, changing the CIE chromaticity coordinates from yellow (0.4343, 0.4857) to white-light (0.3311, 0.3460), the correlated color temperature (CCT) between 3599 K and 5558 K, and color rendering index (Ra) in the range 83.1 to 79.1, under a forward bias current of 350 mA.