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Nuclear reactors operating at high temperatures and in harsh environments can benefit significantly from the use of 316L Oxide Dispersion Strengthened (ODS) steel. This steel is particularly suitable due to its excellent machinability, ductility and ability to maintain mechanical integrity at temperatures above 1000 °C. ODS 316L steel achieves its excellent performance through the dispersion of fine, stable oxide particles in the steel matrix. In addition, ODS 316L steel exhibits excellent corrosion and oxidation resistance, further extending its life and reliability under prolonged exposure to high temperatures and radiation. This study aimed to enhance the corrosion resistance of 316L steel by incorporating yttrium oxide (Y2O3) into its matrix. Samples differed in the way the powders were prepared by mechanical alloying (MA). Powder preparation parameters included time: 5, 10 and 50 hours, rotational speed: 250 rpm, with grinding cycles of 15 minutes and 15-minute intervals for diversion. The materials were manufactured using pulse plasma sintering (PPS) and then compared with standard 316L steel rods. The corrosion resistance of the 316L+Y2O3 was investigated, with Y2O3 added in concentrations of 1 wt.% and 3 wt.% in both nano and micro sizes. Electrochemical techniques including corrosion potential measurements, electrochemical impedance spectroscopy (EIS) and potentiodynamic tests in various solutions (0.5M NaCl, 0.5M H2SO4, 0.5M H2SO4+0.5MNaCl) were performed to assess the corrosion properties. Additionally, the surfaces affected by corrosion were analyzed using scanning electron microscopy (SEM) and optical profilometry. [ABSTRACT FROM AUTHOR]

Magnesium (Mg) alloys are used as biomaterials because of their biocompatibility and stiffness which is similar to that of human bone tissue. This reduces the stress shielding complications associated with bone resorption. Mg is one of the fundamental divalent ions that have an effect on bone-forming cells and also plays an important role in bone metabolism. This is supported by the results of in vivo studies, which indicate that Mg degradation does not damage surrounding tissue and promotes bone remodelling [1]. One of the main drawbacks limiting the wide use of Mg alloys in biomedicine is their low corrosion resistance, and associated high hydrogen release in the surrounding environment which causes pain in the area of implant placement [1-3]. Additive manufacturing is an attractive alternative to conventional manufacturing of Mg alloys, and researchers have so far studied the properties of the following Mg-based alloys:Mg-Al-Zn, Mg-Zn-Zr, and REE-containing alloys [4]. In this research, we propose to develop degradation of Mg-based alloys enriched with Li and Ca which will decrease the density of the alloys and simultaneously improve mechanical properties of the alloys. It is expected to create refined microstructure which should lead to the lowering of the intensity of the occurring corrosion mechanisms. We decided to focused on the Mg-4Li-0.5Ca with single a (Mg) phase. As a reference cast material with the same composition was used. Micro-computed tomography was used to check the porosity of the materials produced. The microstructure of alloys was analyzed through electron back scattered diffraction and phase composition was analyzed using X-ray. Corrosion resistance of both alloys were performed using various electrochemical techniques in phosphate-buffered saline solution (PBS). The materials corrosion rate was investigated by hydrogen evolution tests, and corroded specimens were characterized by SEM and optical profilometer. [ABSTRACT FROM AUTHOR]

SiO(x)-like coatings were deposited on glass slides from a hexamethylsiloxane precursor by plasma-assisted CVD (PACVD). Surface energies (23.1-45.7 mJ m(-1)) were correlated with the degree of surface oxidation and hydrocarbon contents. Tapping mode AFM revealed a range of surface topologies with Ra values 1.55-3.16 nm and RMS roughness 1.96-4.11 nm. Settlement of spores of the green alga Ulva was significantly less, and detachment under shear significantly more on the lowest surface energy coatings. Removal of young plants (sporelings) of Ulva under shear was positively correlated with reducing the surface energy of the coatings. The most hydrophobic coatings also showed good performance against a freshwater bacterium, Pseudomonas fluorescens, significantly reducing initial attachment and biofilm formation, and reducing the adhesion strength of attached bacterial cells under shear. Taken together the results indicate potential for further investigation of these coatings for applications such as heat exchangers and optical instruments.

Fouling-release coatings were prepared from blends of a fluorinated/siloxane copolymer with a poly(dimethyl siloxane) (PDMS) matrix in order to couple the low modulus character of PDMS with the low surface tension typical for fluorinated polymers. The content of the surface-active copolymer was varied in the blend over a broad range (0.15-10 wt % with respect to PDMS). X-ray photoelectron spectroscopy depth profiling analyses were performed on the coatings to establish the distribution of specific chemical constituents throughout the coatings, and proved enrichment in fluorine of the outermost layers of the coating surface. Addition of the fluorinated/siloxane copolymer to the PDMS matrix resulted in a concentration-dependent decrease in settlement of barnacle, Balanus amphitrite, cyprids. The release of young plants of Ulva, a soft fouling species, and young barnacles showed that adhesion strength on the fluorinated/siloxane copolymer was significantly lower than the siloxane control. However, differences in adhesion strength were not directly correlated with the concentration of copolymer in the blends.