Novel antibacterial sodium alginate coatings incorporated with thyme oil and their monoterpenoids (carvacrol, thymol) were obtained in one-step and two-step electrophoretic deposition (EPD) processes on stainless steel substrates. An ecological and economical approach using a larger amount of distilled water instead of ethyl alcohol and the addition of hyaluronic acid in the oil-water emulsion utilized for EPD, while maintaining the high adhesion of obtained coatings to the etched substrate, was developed. The highest adhesion strength revealed coatings deposited in two-steps using a sodium alginate base layer and then a layer rich with a bactericide agent and/or hyaluronic acid. Coatings contained oil drops well distributed in the polymers. The study outlines possible interaction pathways between polymer chains and phytochemicals derived from thyme. The surfaces of the coatings were hydrophilic and their roughness was several times higher than that of the steel substrates. The coated samples demonstrated an improvement in the corrosion resistance of the substrates in Hanks' solution. All tested coated samples exhibited antimicrobial activity and antibiofilm properties. The potential cytotoxicity of the surfaces was confirmed. The developed coatings are promising for protecting temporary steel bone implants against bacterial biofilm formation.

The aim of this study was to develop multicomponent sodium alginate (SA)/curcumin (CURC) coatings enhanced with cellulose nanofibers (CNFs) on titanium substrates. Electrophoretic deposition (EPD) was employed to fabricate the coatings, and their microstructure, adhesion performance, surface properties and antibacterial activity were subsequently investigated. The suspension containing all of the coating components exhibited a highly negative zeta potential at the deposition pH, confirming its suitability for anodic EPD. It was possible to obtain coatings featuring uniformly distributed spherical CURC particles embedded within the polymeric matrix, along with CNFs of varying diameters and lengths. The coating roughness increased with the rise in the CURC content in the suspension used for the EPD. Additionally, all of the coated substrates demonstrated reduced water contact angle in comparison to that of the uncoated chemically etched titanium substrate. A significant reduction in current densities and an increase in impedance values for coated samples suggest an improvement in corrosion immunity in Hanks’ solution in contrast to the bare Ti substrate. Microbiological studies have also confirmed the superb antibacterial effect of elaborated coatings against the S. aureus strain. These findings highlight the potential of SA/CURC/CNF coatings as a promising natural strategy for mitigating biofilm growth on titanium bone implants.

This study aimed to investigate the influence of the synthesis parameters on the corrosion resistance of 3D-printed Inconel 718 components. Samples were fabricated using laser powder bed fusion (PBF-LB/M) with different angles of inclination. Corrosion tests were conducted by immersion for 1000 h in a 3.5% aqueous NaCl solution at 20 °C and 45 °C, and by the potentiodynamic polarization measurements. Detailed analysis of changes in morphology, chemical composition, and roughness of 3D prints was performed using scanning electron microscopy, combined with energy-dispersive X-ray spectroscopy, and optical profilometry. To quantify the dissolution of alloy components during the long-term measurements, the post-corrosion solutions were analyzed using microwave plasma-atomic emission spectroscopy. The obtained results demonstrate that inclination angle significantly affects corrosion rate and electrochemical kinetics, with measurable differences in mass loss, Icorr values, and surface degradation morphology observed between orientations. The findings indicate that build orientation governs microstructural anisotropy and surface characteristics, which in turn influence corrosion susceptibility. The novelty of this work lies in the systematic and multi-method evaluation of inclination angle as an independent structural parameter controlling corrosion kinetics in PBF-LB/M-fabricated Inconel 718, providing new insight into structure-corrosion relationships in additively manufactured nickel-based superalloys.

This study aimed to investigate the electrophoretic deposition (EPD), microstructure, properties, and microbiological activity of multi-component curcumin/chitosan coatings strengthened with cellulose nanofibers (CNF) and carboxymethylcellulose (CMC) on titanium substrates. The findings indicated that pure cellulose dispersed systems had a negative zeta potential, indicating the mechanism of chitosan molecules being adsorbed on the surface of dispersed additives and co-depositing with them on the cathode. CMC and chitosan form a hydrogellike polyelectrolyte complex structure in a dispersed system, preventing the possibility of obtaining homogeneous coatings via EPD regardless of the process parameters. However, coatings containing CNFs proved to be homogeneous and exhibited high adhesion strength and enhanced scratch resistance, and thus have been selected as the most promising. Their microstructure consisted of submicrometric spherical curcumin particles and CNFs of various sizes homogeneously embedded in the chitosan matrix. Elaborated materials exhibited increased surface roughness compared to the uncoated substrate, as well as moderate hydrophobicity (water contact angle 92.4 degrees +/- 1.2 degrees). Electrochemical studies confirmed that the CNF/curcumin/chitosan coatings improved corrosion resistance compared to the bare titanium substrate and the coating without CNF. The CNF/ curcumin/chitosan surface also showed significant activity against S. aureus ATCC (R) 25,923 in terms of bactericidal activity and against biofilm formation.

The objective of this study was to investigate the influence of additive manufacturing parameters, specifically using laser powder bed fusion (LPBF), and surface finishing methods on the corrosion rate and behavior of maraging steel M350 components. Samples were fabricated via LPBF employing varying laser powers (80 W, 100 W, and 120 W) and subsequently subjected to mechanical polishing. Corrosion performance was evaluated through 450 h immersion tests in a 3.5% aqueous NaCl solution and potentiodynamic polarization measurements. Microstructural characterization and surface topography assessments were performed using optical microscopy, scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM-EDS), and profilometry. The results demonstrate a strong influence of temperature, manufacturing parameters, and polishing on corrosion processes. At room temperature, higher laser power reduced corrosion rates due to better powder consolidation and lower porosity, whereas at 45 °C, the trend reversed, with the highest corrosion rates observed for samples produced at 120 W. Mechanical polishing significantly reduced surface roughness (Ra from ~7–10 μm to ~0.6–1 μm) but did not improve corrosion resistance; in some cases, it increased corrosion rates, likely due to stress redistribution and exposure of subsurface defects. Potentiodynamic tests confirmed that higher laser power reduced corrosion current density for unpolished surfaces, but polishing increased current density at 80 W more than twofold. The findings indicate that optimizing LPBF process parameters is crucial for improving the corrosion resistance of M350 steel. High laser power (≥120 W) is beneficial at ambient conditions, while lower powers (80–100 W) perform better at elevated temperatures. Mechanical polishing alone is insufficient for enhancing resistance and should be combined with stress-relief and porosity-reduction treatments. These results provide guidelines for tailoring additive manufacturing strategies to ensure reliable performance of M350 steel in chloride-rich environments.

Glass wool waste constitutes a large amount of waste both in the production process and after the demolition of buildings. The storage of these materials in landfills is associated with their large volume and low mass which results from their low density. Considering the principle of a life cycle assessment, the possibility of recycling this type of waste should be ensured. The basic problem with the recycling process is the removal of the binder that connects the glass wool fibres before returning it to the production process. The paper presents the results of research on the process of heat treatment of glass wool with various temperatures and heating rates. The process of sinter formation and the possibilities of avoiding their formation were analysed. For this purpose, a series of tests in the field of thermal analysis were carried out, in which the temperature ranges in which heat was released were identified. Furthermore, a series of tests were carried out on cube samples with dimensions of 20 × 20 × 20 mm in a chamber furnace. Based on the research conducted, assumptions were developed for the heat treatment process of glass wool waste, which allows the removal of organic substances and prevents the formation of sinters.

In this work, we show the in vitro anticancer potential of surgical wires, obtained from zinc (ZnMg0.004) or magnesium (MgCa0.7) alloys by spatial technology comprising casting, extrusion, and final drawing processes. We also present the selective anticancer effects of applied soluble multilayer nanocoatings of zinc and magnesium onto titanium surfaces using the pulse laser deposition method. In the latter, the titanium samples were produced via 3D printing using the selective laser melting method and coated with various combinations of zinc and magnesium layers. For cytotoxicity studies, human dental pulp-derived stem cells (hDPSCs) and human osteosarcoma SaOS-2 cell line were used as representatives of healthy and cancer cells. Cells were examined against the 0.3–3.0 cm2/mL material extract ratios obtained from experimental and steel surgical wires, the latter being the current clinical industry standard. The MgCa0.7 alloy wires were approx. 1.5 times more toxic to cancer cells at all examined extract ratios vs. the extracts from steel surgical wires that exhibited comparable toxicity towards healthy and cancer cells. The ZnMg0.004 alloy wires displayed increased toxicity towards cancer cells with decreasing extract ratios. This was also reflected in the increased anticancer effectiveness, calculated based on the viability ratio of healthy cells to cancer cells, from 1.1 to 4.0 times. Healthy cell viability remained at 80–100%, whereas cancer cell survival fluctuated at 20–75%, depending on the extract ratio. Furthermore, the culture of normal or cancer cells on the surface of Zn/Mg-coated titanium allowed us to select combinations of specific coating layers that yielded a comparable anticancer effectiveness to that observed with the experimental wires that ranged between 2 and 3. Overall, this work not only demonstrates the substantial anticancer properties of the studied wires but also indicates that similar anticancer effects can be replicated with appropriate nanocoatings on titanium samples. We believe that this work lays the groundwork for the future potential development of the category of new implants endowed with anticancer properties.

Additive manufacturing of Inconel 625 components attracts great interest due to its ability to produce parts with complex geometries that are needed for high-temperature applications in the aerospace, energy, automotive and chemical industries. To take full advantage of the potential of additive manufacturing, an in-depth understanding of the effects of prolonged high-temperature annealing on microstructure and hardness evolution is needed. Previous research in this field has mainly focused on a limited range of temperature and time. This study aims to determine the effect of prolonged high-temperature annealing on the evolution of intermetallic phases and carbides, as well as changes in the dislocation substructure of Inconel 625 superalloy additively manufactured by laser powder bed fusion subjected to stress relief annealing and subsequent isothermal annealing at a temperature up to 800 °C for 5–500 h. The microstructure development is correlated with hardness behaviour. It is determined that the microstructure evolution proceeds in four stages with temperature and time increase. In the initial stress-relieved condition, a cellular microstructure with nano-sized precipitates of the Laves phase and NbC carbides at the cell walls occurs, and hardness is equal to 300 HV10. In the 1st stage of the microstructure evolution, the γ'' phase particles precipitate on the cell walls, which results in hardening up to 383 HV10 in the specimen annealed at 700 °C for 5 h. The 2nd stage involves the precipitation of the γ'' phase both on the cell walls and inside the cells, as well as the formation of dislocation networks, which contribute to the softening effect and hardness drop to 319 HV10. In the 3rd stage, at temperature 700 and 800 °C, the δ phase, M 23 C 6 carbides, and the Laves phase precipitate and grow, and the subgrain boundaries are formed. The hardness is in the range of 340–350 HV10 and is higher than in the 2nd stage. In the 4th stage, as the annealing time is increased at a temperature of 800 °C, the δ phase and M 23 C 6 carbides coagulate, and the Laves phase particles spheroidize or partially dissolve. Very intense precipitation and growth of the hard δ phase particles provide an increase in hardness to 402 HV10. As a result of systematic studies, the various strengthening and softening mechanisms acting during high-temperature annealing are determined. Graphical abstract

Currently used TEG modules have low efficiency of about 5%. The energy generated by the TEG module depends on the temperature difference between the module surfaces. Heat exchange between the heat source and the module surface takes place through the contact between two rough solid surfaces. This creates contact resistance. It can be reduced by using a substance filling the empty spaces between the contact surfaces and applying pressure. During the tests, the efficiency of electricity generation with a thermoelectric generator was measured (TEG) at various pressure forces. The tests were carried out at a pressure force of 250 N, 500 N, 750 N and 1000 N. The selected values of pressure do not exceed the limit value arising from the thermoelectric generator (TEG) design. A copper element constituting the heat source was heated in a furnace. Next, it was pressed at an adequate force to the generator, which was placed on a water cooler. The impact of conductive materials placed between the faces of the heat source and the TEG on the generation of electricity was examined. At low forces, the use of a thermal pad as an intermediary substance does not result in improved heat transfer in the heat source—TEG generator system. Better filling of voids is provided by thermally conductive paste due to its properties.

This research explores the welding process of a high-entropy CrMnFeCoNi alloy with iron, unraveling the intricate chemical compositions that materialize in distinct regions of the weld joint. A mid-wave infrared thermal camera was deployed to monitor the cooling sequences during welding. A thorough analysis of the metallographic sample from the weld joint, along with measurements taken using a nano-hardness indenter, provided insights into the hardness and Young's modulus. The element distribution across the weld joint was assessed using a scanning electron microscope equipped with an EDS spectrometer. Advanced techniques such as X-ray diffraction and Mössbauer spectroscopy underscored the prevalence of the martensitic phase within the weld joint, accompanied by the presence of bcc (iron) and fcc phases. In contrast, Young's modulus in the base metal areas displayed typical values for a high-entropy alloy (202 GPa) and iron (204 GPa). The weld joint material displayed substantial chemical heterogeneity, leading to noticeable concentration gradients of individual elements. The higher hardness noted in the weld (up to 420 HV), when compared to the base metal regions (up to 290 HV for CrMnFeCoNi alloy and approximately 150 HV for iron), can be ascribed to the dominance of the martensitic phase. These findings provide valuable insights for scenarios involving diverse welded joints containing high-entropy alloys, contributing to our understanding of materials engineering.

In the production of beverage cans, “short can” defects in the form of material discontinuities can occur during the deep drawing of cylindrical thin-walled aluminium products. These defects have a significant impact on production efficiency and scrap generation, and their occurrence is influenced by material and process properties. To determine the main influence of material on defect occurrence, two approaches were used: deterministic analysis of mechanical properties and microstructure, as well as statistical processing of production data using decision tree models. The latter approach was found to be more efficient, and a numerical tool was developed based on this approach to predict and reduce defect occurrence in the production process.

The aim of this work was to investigate the features of microstructure, phase composition, mechanical properties, and thermal stability of the two-component melt-spun Ni55Fe20Cu5P10B10 alloy. The development of the microstructure after heating to elevated temperatures was studied using scanning electron microscope and in situ high temperature X-ray diffraction. The high-temperature behavior of the two-component melt-spun Ni55Fe20Cu5P10B10 alloy and Ni40Fe40B20, Ni70Cu10P20, and Ni55Fe20Cu5P10B10 alloys melt-spun from single-chamber crucible was investigated using differential scanning calorymetry at different heating rates and by dynamic mechanical thermal analysis. The results show that band-like microstructure of the composite alloy is stable even at 800 K, although coarsening of bands forming the microstructure of the ribbons is observed above 550 K. Plastic deformation is observed in the composite previously heated to temperatures of 600–650 K. The properties of the composite alloy are generally different than the properties obtained for the melt-spun alloy of the same average nominal composition produced traditionally. Additionally, the mechanical and the thermal properties in this composite are inherited from the amorphous state of alloys that are precursors for two-component melt spinning (TCMS) processing.

Nanotechnology is a very attractive tool for tailoring the surface of an orthopedic implant to optimize its interaction with the biological environment. Nanostructured interfaces are promising, especially for orthopedic applications. They can not only improve osseointegration between the implant and the living bone but also may be used as drug delivery platforms. The nanoporous structure can be used as a drug carrier to the surrounding tissue, with the intention to accelerate tissue–implant integration as well as to reduce and treat bacterial infections occurring after implantation. Titanium oxide nanotubes are promising for such applications; however, their brittle nature could be a significantly limiting factor. In this work, we modified the topography of commercially used titanium foil by the anodization process and hydrothermal treatment. As a result, we obtained a crystalline nanoporous u-shaped structure (US) of anodized titanium oxide with improved resistance to scratch compared to TiO2 nanotubes. The US titanium substrate was successfully modified with hydroxyapatite coating and investigated for bioactivity. Results showed high bioactivity in simulated body fluid (SBF) after two weeks of incubation.

Here, we demonstrate heteroepitaxial growth of MgO/TiN thin films on flexible metal foil of copper substrates using pulsed laser deposition. X-ray and electron diffraction measurements revealed that the epitaxial MgO/TiN bilayer was oriented along [002] direction. The large mismatch between TiN film and Cu substrate was effectively reduced by the 5/6 and 6/7 variations of domains. Despite the local irregularity of misfit dislocations at TiN/Cu, the domain-matching epitaxy paradigm is a remarkably accurate theory. MgO/TiN bilayer is chemically homogeneous and Mg, Ti, or Cu atoms do not segregate into the low-angle grain boundaries regardless of MgO/TiN films thickness. Thus, it appears that thickness may be reduced up to the value in which TiN fully covers the rough surface of Cu tape. Unfortunately, issues related to the presence of in-plane TiN contraction, probably generated by the difference in thermal expansion coefficient, and the origin of misfit dislocations irregularity at TiN/Cu interface remain unresolved. Our findings can make a substantial contribution to further research on Cu-based coated conductors and help in better understanding the ways that MgO/TiN bilayer are grown on Cu tape.

The aim of the work was to obtain thin bismuth oxide films containing, at room temperature, the Bi1,5Er0,5O3 phase. This phase corresponds to the structure of the high-temperature δ-Bi2O3 phase, in pure bismuth oxide, characterized by the highest ionic conductivity of all known solid state ionic conductors. The high-temperature δ-Bi2O3 phase with the face centered cubic structure, in pure bismuth oxide, occurs only at temperature above 730°C. Stabilization of the δ-Bi2O3 phase at room temperature was achieved by an addition of the erbium together with the employment of the Pulsed Laser Deposition (PLD) technique. The influence of an amount of Er alloying and the film thickness on surface morphology, microstructure, phase composition of thin films were investigated. The velocity of deposition of thin layers of bismuth stabilized with erbium in the PLD process using the Nd: YAG laser was about 0.5 nm/s. The investigation results of erbium doped bismuth oxide thin films deposited onto (0001) oriented Al2O3 monocrystalline substrate are presented. Thin films of uniform thickness, without cracks, and porosity were obtained. All deposited thin films (regardless of the film thickness or erbia (Er2O3) content) exhibited a columnar structure. In films stabilized with erbium, up to approx. 250 nm thickness, the columns have a diameter at the base from 25 to 75 nm. The columns densely and tightly fill the entire volume of the films. With increasing of the film thickness increases, porosity also significantly increases. In thin layers containing from 20 to 30 mole % Er2O3 the main identified phase at room temperature is Bi1.5Er0.5O3. It is similar to the defective fluorite-type structure, and belongs to the Fm-3m space group. This phase corresponds to the structure of the high-temperature δ-Bi2O3 phase in pure bismuth oxide.

Preliminary studies on the sediments collected from water meters of Krakow water supply system were performed in the cooperation with the Municipal Water Supply and Sewage.Creation and deposition of sediments on the measuring devices installed in the water supply system is a serious technological and economical problem for water companies, defectively operating for this reason water meters must be replaced.It is evident that knowledge of the chemical and phase composition of sediments is an important step towards resolving the problem of impurities in water supply systems.Four different samples of sediments, coming from water meters, were investigated using the proton-induced X-ray emission, the X-ray diffraction, the Fourier transform infrared and Raman spectroscopy.The X-ray methods revealed presence of amorphous and fine-crystalline phases as well as high content of iron-based compounds.As a crystalline phase, the most frequently appeared: goethite, lepidocrocite, iron oxides (hematite, maghemite, magnetite), calcium carbonate, and quartz.In one of the samples, the nanocrystalline phase was found and identified as hydrous iron oxyhydroxide ferrihydrite.Vibrational spectroscopy methods confirmed the composition of crystalline phases as well as enabled to estimate the abundance of amorphous phase in samples.

Naukowym i technologicznym celem badań było wytworzenie nanostrukturalnych powłok FeCuAl-Al2O3, WC-CoAl, Ni-Sn, TiC/Ti o grubości od 45 do 500 µm

Nanostructured, biocompatible, TiC/Ti Supersonic Cold Gas Sprayed coatings were deposited onto a Ti6Al4V alloy and their microstructure, wear resistance and hardness were investigated. The starting nanostructured powder, containing a varied mixture of Ti and TiC particles, was produced by high energy ball milling. Scanning and transmission electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction were used for structural and chemical analyses of powder particles and coatings. Coatings, 250-350 μm thick, preserving the nanostructure and chemical powder composition, with low porosity and relatively high hardness (~850 HV), were obtained. These nanostructured TiC/Ti coatings exhibited better tribological properties than commonly used biomedical benchmark materials, due to an appropriate balance of hard and soft nano-phases.

We studied changes of morphology and magnetic properties of Co/Cu multilayered nanowires, electrodeposited in polycarbonate membranes, as a function of Cu layer thickness. The morphology and structure of wire assemblies with an average diameter of 200 nm and length of 10 mu m, investigated by X-ray diffraction and scanning electron microscopy techniques, revealed polycrystalline structure of Cu and Co layers with smooth lateral surface of nanowires. Overdeposited nanowires created caps which showed flower-like dendrites with shape changing as a function of Cu thickness and electrodeposition parameters. Chemical composition of Co and Cu nanowires analysed by energy dispersive spectroscopy and proton induced X-ray emission showed Cu nanowires free from Co atoms while in Co nanowires, Cu contamination with concentration below 10% was observed. The oxidation traces observed in single-component Cu nanowires did not appear in multilayered nanowires. Magnetic measurements indicated easy axis of magnetization in membrane plane for nanowires with Cu thickness smaller than 20 nm, whereas for larger Cu thicknesses isotropic orientation of magnetization was observed. The presence of Cu atoms in single-component Co nanowires resulted in the appearance of magnetic anisotropy with easy axis along nanowire axis and the increase of coercivity value.

SiO2/Ni nanocomposite coatings containing well-dispersed SiO2 nanoparticles were electrodeposited from a sulphate bath with and without the addition of polyethylenimine (PEI) as a cationic surfactant. The surface morphology and microstructure in the cross-sections of the deposited nanocomposites were examined by scanning electron microscopy. More detailed microstructure characterization was performed using transmission, scanning-transmission and high resolution transmission electron microscopy. It was determined that the addition of 0.05 g/L and 0.1 g/L of PEI allows the incorporation of SiO2 nanoparticles in the nickel matrix to be increased in comparison with the nanocomposite deposited without a surfactant. Based on high spatial resolution microanalysis, performed using high count rate energy dispersive spectroscopy of characteristic X-rays in the scanning-transmission mode, the distribution of SiO2 nanoparticles in the nanocomposite was visualized on elemental maps. Image analysis of the electron microscopy images enabled the mean equivalent circle diameters of grains in the nickel matrix to be determined, together with the volume fraction of SiO2 nanoparticles in the nanocomposites. The volume fraction of SiO2 clusters in the SiO2/Ni + PEI nanocomposites with the addition of 0.05 g/L and 0.1 g/L of PEI is equal to 18.4% and 13.3%, respectively. Furthermore, the PEI addition allows the nickel grain size in the matrix to be reduced. The combination of different imaging techniques confirmed that PEI is not only present as a surfactant in the electrolytic bath, but also incorporates into the microstructure of the nanocomposite. Nanocomposites electrodeposited in the presence of 0.05 g/L of PEI exhibit higher hardness, good tribological properties and improved corrosion resistance. Although increasing the PEI concentration in the bath up to 0.1 g/L strongly promotes grain size reduction and increase of the SiO2 volume fraction, it also causes an increase in the PEI fraction embedded in the microstructure, which results in deterioration of the properties of the SiO2/Ni + PEI nanocomposites.