Chromium nitride (CrNx) thin films were deposited by DC magnetron sputtering under increasing N2 flow to investigate their suitability for piezoresistive sensing applications. Structural, morphological, and electrical properties were systematically studied as a function of nitrogen incorporation. SEM and AFM analyses revealed a transition from coarse columnar metallic Cr to dense, nanocrystalline CrNx films as N2 flow increased, with a temporary amorphous-like regime at low nitrogen content (10 sccm). XRD confirmed the formation of the FCC-CrN phase for N2 flows >= 20 sccm, accompanied by an increase in crystallite size. Electrical resistivity similarly evolved from metallic behavior to semiconducting characteristics, driven by Cr-N bonding and reduced carrier density. Piezoresistive testing under cyclic bending demonstrated stable, repeatable, and linear responses for CrNx films at higher nitrogen content, yielding gauge factors of 3.9 +/- 0.3 (20 sccm) and 4.5 +/- 0.3 (25 sccm), outperforming pure Cr and comparable to high-performance metallic strain gauges. Thermoresistive evaluation revealed negative TCR values, typical of transition-metal nitrides, with improved thermal stability at higher nitrogen content. These findings establish sputtered CrNx thin films as promising candidates for multifunctional, mechanically robust, and thermally tolerant micro-scale pressure and temperature sensors, relevant for Industry 4.0/5.0 monitoring systems and flexible electronics.

The properties of a certain compound developed as a thin film can be influenced either by modifying the composition (mass ratio of the constituent elements) or, for a certain composition, by modifying the structural architecture. TiN compound, developed as a thin film, is well known, especially for its mechanical and tribological properties. For its stoichiometric aspect, it was found that modifying the structural design of the compound can expand its application area (from the perspective of thermal, electrical, optical properties). It is of particular interest to investigate the consequences of these structural architectural modifications taking into account the potential reduction in mechanical and tribological performance. This study focuses on the preparation of nanostructured thin films and the tailoring of their properties by employing inclined and zigzag-like growth architectures. To achieve this, TiN thin films were deposited on stainless steel and silicon substrates using Oblique Angle Deposition (OAD) with a DC reactive magnetron sputtering system. The mechanical and tribological properties of the films were found to be strongly influenced by their roughness and porosity values evolution, which resulted from the specific characteristics of the OAD geometry. As the deposition configuration shifted from conventional growth geometry (normal incidence) to OAD with inclined and zigzag geometries, both surface porosity and roughness values increased significantly due to the shadowing effect and comparatively low thermalization degrees. This led to a noticeable decrease in hardness and Young's modulus values, friction coefficient and wear rates, along with a reduced scratch resistance of the thin films. However, the values obtained were consistent with those reported in the literature, confirming the thin films' good applicability and suitability for a variety of applications. Hardness/Young's modulus values varied from about 27/260 GPa for the samples grown in the conventional geometry, reducing to approximately 13/210 GPa and about 10/190 GPa for the inclined and zigzag grown TiN films, respectively. The same reduction trend was also observed in the adhesion behaviour, where a decrease of about 50 % was observed for the critical loads (Lc2 and Lc3) when going from conventional to inclined and from this last to zigzag growth geometries. Finally, and keeping this tendency to a slight degradation of the mechanical and tribological behaviour, the friction coefficient, mu, increased from 0.20 for the conventional grown TiN sample to about 0.69 and 0.81 for the inclined and zigzag grown TiN sets.

Work performed in confined and low-height spaces (NSLH) is relatively common across several industries, yet it has not been adequately addressed from an ergonomic perspective. Such activities require workers to adopt awkward postures, most often with the trunk bent and rotated, while handling loads positioned at varying distances from the body. These conditions lead to rapid fatigue, musculoskeletal strain, and, in the long term, may cause serious health disorders. Traditional ergonomic risk assessment methods, such as REBA, RULA, or QEC, were initially applied in these situations; however, the results were unsatisfactory. Their broad applicability and reliance on calculation tables that incorporate factors irrelevant to NSLH tasks prevent them from providing an accurate evaluation of ergonomic risks in these environments. To overcome these limitations, a new assessment method, RALH (Risk Assessment for Narrow Spaces with Low Height), was developed. The method aims to evaluate ergonomic risks in contexts where workers cannot maintain an upright posture, resulting in significant stress on the spinal column, particularly in the lumbar and cervical regions. The RALH methodology incorporates parameters such as trunk inclination, trunk rotation, load weight, distance between the body and the load, exposure duration, and the worker’s physical fitness. A dedicated software tool, ERGO Agent—RALH, was designed to implement this methodology, providing structured data collection, parameter normalization, and ergonomic risk calculation. Case studies, including distribution agents working inside van cargo compartments, demonstrated that the method produces accurate and objective results. Beyond diagnosis, RALH also supports the development of preventive strategies, such as equipment optimization, task allocation, worker training, and physical conditioning. Overall, the RALH method is a practical tool for improving occupational health and efficiency in NSLH environments, where traditional ergonomic approaches are insufficient.

Fiber-reinforced composites are gaining more importance across different fields such as aeronautics, automotives, high-performance sporting equipment, etc., where decreasing weight while improving mechanical properties of polymers is fundamental. This article explores the mechanical behavior of fiber-reinforced polyester composite materials, highlighting their advantages and applications in various industrial fields. Usually, composite materials consist of a polyester matrix reinforced with different types of fibers, such as glass, carbon, or Kevlar, which provide superior mechanical characteristics. This study analyzed the tensile strength, bending resistance, and resilience of glass fiber composites, emphasizing the importance of proper fiber selection and manufacturing processes. These materials stand out for their excellent strength-to-weight ratio and are widely used in the fabrication of tanks in various industries. Experimental results demonstrated tensile strength (Rm) around 115 MPa, Shore D hardness values of 88 units, and impact toughness (resilience) of 2.7 J/cm2. Based on the composite materials’ behavior in testing, the article further offers practical recommendations for the effective deployment of these composites in the fabrication of various types of industrial reservoirs.

In Romania, most workers' health problems are caused by work situations in which ergonomic principles and regulations are not respected. It was found that in many situations, not only the workers, but sometimes even those responsible for safety and health at work, do not know these ergonomic principles and rules, this fact reveals that, at the enterprise level, there is no management conscious, assumed and planned for the ergonomic risks. In this article, we propose a systematic, step-by-step approach to effective management of ergonomic risks. This methodology was implemented in several companies in Romania, and the results, both in terms of workers' health and work productivity, were excellent.

The comfort of a worker while performing any activity is extremely important. If that activity extends beyond a person’s capacity to withstand physical and psychological stress, the worker may suffer from both physical and mental ailments. Over time, if the stress persists, these conditions can become chronic diseases and can even be the cause of workplace accidents. In this research, a methodology was developed for the rapid assessment of ergonomic risks and for calculating the level of ergonomic comfort in the workplace. This methodology uses artificial intelligence through a specific algorithm and takes into account a number of factors that, when combined, can have a significant impact on workers. To achieve a more accurate simulation of a work situation or to evaluate an ongoing work situation, and to significantly correlate these parameters, we used logarithmic calculation formulas. To streamline the process, we developed software that performs these calculations, conducts a rapid assessment of ergonomic risks, estimates a comfort level, and proposes possible measures to mitigate the risks and effects on workers. To assist in diagnosing the work situation, we used a neural network with five neurons in the input layer, one hidden layer, and two neurons in the output layer. As a result, most work situations, in any industrial field, can be quickly analyzed and evaluated using this methodology. The use of this new analysis and diagnosis tool, implemented through this new research technology, is beneficial for employers and workers. Moreover, through further developments of this methodology, achieved by increasing the number of relevant input parameters for ergonomics and integrating advanced artificial intelligence systems, we aim to provide high precision in assessing ergonomic risk and calculating the level of ergonomic comfort.

This study analyses the opinion of 200 employees who participated in the first online training in the field of occupational health and safety systems (OSHs) from Romania, for which an online platform was used, with the records on electronic files with a qualified electronic signature. The usefulness of this online training was analyzed based on the voluntary answers of the participants to a questionnaire related to 14 questionnaire items (QIs). In order to correctly interpret the results of the applied test, a statistical processing of the answers was carried out, and the following were calculated (using SPSS 23.0 software): the factor analysis, the Kaiser–Meyer–Olkin (KMO) test, the Bartlett’s test, the extraction method, the Principal Component Analysis (PCA), the Cronbach alpha test and the Kruskal–Wallis H-test. The calculations highlighted two essential strategies: “Availability for online training” (S1) and “Challenges of online training” (S2). The conclusion of this study provides an overview of the importance of online training strategies in OSH activity and can help researchers and practitioners to improve this activity, reducing the rejection of its use among managers and authorities, thus providing a new reference for future research.

Titanium-copper thin films were prepared by Glancing Angle Deposition (GLAD) to assess their suitability for temperature sensors, by measuring the temperature resistance coefficient (TCR). The films were deposited with zigzag and spiral architectures, while the substrate holder was maintained at a fixed angle of alpha = 20 degrees relative to the incident flux of the sputtered particles. The films were produced through DC co-deposition magnetron sputtering, using two targets of pure Ti and Cu. A wide range of compositions was achieved by varying the current on the Cu target from 6 mA up to 20 mA. The obtained architectures were stabilized through in-vacuum annealing treatments to minimize the hysteresis effects of the temperature on the electrical resistance of the films. The sheet resistance showed a direct correlation with the formation/precipitation of the Ti-Cu intermetallic phases in the film. The measured Temperature Coefficient of Resistance (TCR) values ranged from - 1.08x10- 3 to - 5.1x10- 3 degrees C- 1, closely resembling the absolute value of platinum's TCR (3.93x10- 3 degrees C- 1). Moreover, the elimination of hysteresis from the TCR plot and consistent results obtained during multiple cycles of heating and cooling highlight the potential of titanium copper thin films as promising alternatives for temperature sensors.

When training engineers and team leaders, it is crucial to focus on cultivating essential skills for safety at work, required in both theoretical design and practical application. One such crucial skill is the ability to assess professional risks across all engineering domains. To promote sustainable safety awareness in workplaces and to initiate the early education and training of engineering workers through training and testing, we developed a software application and tested it among Romanian workers. This software facilitates the management of the entire risk assessment process, further enhancing the training experience. The presented methodology used for learning, testing, and assessing the skills of engineering workers and for risk assessment, called EL-PRAI (Engineering Learning and Professional Risks Assessment in Industry), was tested on 238 workers (engineers and team leaders) from different engineering fields. The results obtained and the workers’ positive feedback support a broader use of the software application for educating engineers and team leaders on workplace safety. If the engineers and team leaders understand the risks at their workplaces well, they will be able to properly train their subordinate workers and order appropriate measures before starting activities.

This study investigated the impact of the nanostructure design of titanium nitride (TiNx) thin films on their optical, electrical and thermal properties. The growth designs of the films were tailored using conventional sputtering (series 1) and GLancing Angle Deposition (GLAD) geometries (series 2 and 3). The results showed the potential to modify the properties of thin films by adjusting their nanostructure design, rather than changing their composition. TiNx thin films prepared by GLAD, revealed wider and more significant variations in optical and electrical properties, while the thermal properties seemed to be more affected by the structural changes promoted by the N content in the films. GLAD geometries resulted in the reduction of the film's reflectivity, and colour coordinates, as well as an increase in the electrical resistivity. The thermal parameters of effusivity ratio and diffusivity were reduced as the N/Ti ratio increased.

In order to carry out an ergonomic assessment of the entire working situation in the industrial field, we have created and implemented an ergonomic risk assessment methodology—Ergonomics Risk Assessment Methodology in Industry (ERAI)—which takes into account a number of aspects that have a major impact on the physical condition and health of workers as well as on their efficiency. This study was conducted on 18 assembly line workers. ERAI identifies the level of exposure of the neck, trunk, shoulders/arms, wrists/hands and feet and can be used using printed forms, but it is preferred to use software that implements this method, thus avoiding errors. For this purpose, we have developed the ERAI software application that allows the management of the entire evaluation project. The main activities, the sub-activities carried out by the worker, together with the anthropometric characteristics are entered into the application, evaluating the posture of each part of the body, the effort exerted, the physical condition, etc. ERAI highlights the possible problems related to the physical condition of workers, e.g., there are three workers with a weaker physical condition, and the score for them is between 258 and 282, which is very high compared to the score of the other workers, which varies between 43 and 141. The results obtained with ERAI provide a correct diagnosis, facilitating effective ergonomic interventions to reduce the level of exposure.

The continuous development of modern industries rises the necessity for functionally graded materials. This research starts from the consideration that the incorporation of SiC particles in the molten aluminum alloy can be difficult due to the very low wettability of SiC particles. In order to increase their wettability, SiC particles were covered with a layer of metallic copper. The incorporation of SiC particles into the aluminum alloy mass was performed by centrifugal casting. The secondary hypoeutectic Al-Si alloy used in this study was elaborated within the crucible of a resistors heated furnace. The metallic coating of SiC particles, in addition to the effect of increasing their wettability by molten metal, also has a role in preventing the formation of aluminum carbide in case of heating above 700 °C. A great amount of attention was paid to the parameters used during the centrifugal casting process. The results showed that adjusting the proportion of SiC particles within the composite allows us to obtain values of the thermal expansion coefficient within previously established limits. The present work demonstrates that the coating of SiC particles covered with a thin layer of metallic Cu creates the conditions to easily incorporate them into the molten Al mass, thus obtaining FGMs with controlled properties.

An improvement in the hardness, wear and corrosion resistance of a thermal-sprayed nickel-aluminium coating has been described in this paper, by using a post-deposition annealing treatment in a vertical concentrated solar radiation furnace at Plataforma Solar de Almeria, Spain. Annealing temperatures between 900 and 970 degrees C were used. It has been determined that the heat treatment leads to a 56% increase in hardness, 65% increase in scratch resistance and coating adhesion to the substrate, coupled with a 20% improvement in wear resistance, compared to the non-annealed reference. The improvement in mechanical properties has been related to increased heating gradient, formation of intermetallic NixAl compounds in the structure of coatings, as well as to a better compacting of coated assembly. The solar annealing treatment leads also to an improvement in the properties of coatings, with up to 87% in terms of corrosion resistance, and 20% in terms of wear resistance, comparing to the reference.

Abstract Study on the tool wear of cutting white marble by multi-layer diamond coated tool, and discussion of the wear characteristics and failure mechanism of the tool are presented in this paper. Multi-layer diamond coating was prepared by hot filament chemical vapor deposition (HFCVD). It was deposited on the surface of cemented carbide ball-end milling tool. The surface appearance of the tool was analyzed by an optical microscope. The grain state was analyzed by scanning electron microscopy. Comparing the surface morphology of the cutting for 1h, the area where the coating peeled off became larger when the cutting tool was cut for 2 hours, and the falling range was expanded along the cutting-edge direction while the flank surface was expanded, and the tool joint wear was severe. The composition of diamond grains was investigated by Raman spectroscopy. Comparing the surface morphology of the cutting for 1h, the area where the coating peeled off became larger when the cutting tool was cut for 2 hours, and the falling range was expanded along the cutting-edge direction while the flank surface was expanded, and the tool joint wear was severe.

This study reports the assessment of the mechanical properties of intermetallic titanium thin films, doped with different amounts of aluminium, copper, silver, and gold, aiming their use as biopotential electrodes for non-invasive physiological monitoring. The four binary thin film systems, Ti-Me (Me = Al, Cu, Ag, Au), were prepared by DC magnetron sputtering, placing different number of Me pellets on a pure Ti target. The use of a Ti-composed target gave rise to a wide range of compositions, resulting in three distinctive zones of (micro) structural features, identified in all the prepared systems. In the first zone, a Ti-rich one, the films behaved like solid solutions, developing Ti-like microstructures. As the Me/Ti atomic ratio increased, the formation of intermetallic phases played the leading role and it became possible to observe two different microstructural trends, clearly related to the Me type. This zone was identified as an intermetallic region. In the third zone, a Me-rich one, the microstructures displayed by the different films (Me/Ti > 1.0) showed to be dependent on the Ti solubility into Me. The assessment of the mechanical properties revealed an improved hardness and stiffness with the Me addition, directly related to the formation of intermetallic compounds in different degrees of crystallinity. Moreover, the adhesive strength between the substrate and the coating was higher for the films deposited in the intermetallic zone, more evident in the films prepared with Au, Cu and Ag, in this order. The hardness enhancement was especially evident for the thin films presenting microstructures typical of thin film metallic glasses (TFMGs), Ti-Au and Ti-Cu, about twice the values exhibited by the Ti-Al and Ti-Ag ones. Furthermore, the toughness of these metallic glass-like thin film systems was remarkable, more evident within the Ti-rich zone, presenting H/E ratios close to 0.1 and good elastic recoveries. In contrast, the typical columnar morphologies, combined with the brittle intermetallic structures of the Ti-Ag and Ti-Al films, proved to be less resistant to the plastic deformation (H/E < 0.04), despite the improved elasticity presented by the Ag-rich films.

Additive manufacturing (AM) is a type of production technology which consists of stacking and unifying individual layers, to form a three-dimensional part with complex geometry, usually unobtainable by other means of production. Due to its working principle, i.e. stacking layers, the mechanical characteristics of the built part could be influenced by the construction angle. For metallic additively manufactured parts, it was reported that the mechanical behavior, cyclic deformation and fatigue behaviors are clearly influenced by the build orientation. To date, the number of reports concerning the mechanical behavior of polymer AM parts is relatively limited. Hence, the aim of this study was to assess whether the build orientation will have an impact on the traction and compression characteristics of standard samples built by FFF (Fused Filament Fabrication), from polylactic acid filament. Samples were built at various inclination degrees. It was observed that the build orientation has a significant effect on the mechanical properties of parts, better behavior being observed for the specimens printed at 0 degrees building orientation

This paper presents an evaluation regarding the influence of substrate material characteristics and deposition parameters on the tribological behaviour of carbon-based coatings. Chromium nitride ceramic interlayers and carbon-based thin films were deposited by magnetron sputtering on hardened AISI 5115 (16MnCr5) case hardening steel. The physical vapour deposition (PVD) deposition was performed at three different temperatures: 180 degrees C, 200 degrees C and 250 degrees C. The chemical composition of the samples was assessed by Rutherford Backscattering Spectroscopy (RBS), the structure by X-ray Diffraction (XRD), and the surface morphology by Atomic Force Microscopy (AFM). The surface chemistry was analysed by X-ray Photoelectron Spectroscopy (XPS) and Raman Spectroscopy. The coatings are homogeneous, amorphous, with a smooth surface. The mechanical behaviour has been assessed on a pin-on disk rotational tribometer (wear characteristics), on a micro scratch tester (adhesion to the substrate), by ball-cratering (film thickness) and by nanoindentation (hardness and the modulus of elasticity). A strong correlation has been observed between the substrate characteristics and, more importantly, the deposition temperature, and the mechanical properties of the assembly. The fracture toughness is positively influenced by the presence of the ceramic chromium nitride interlayer. The modulus of elasticity and friction coefficient (both in dry and lubricated conditions) are decreased for higher deposition temperatures, however the higher deposition temperature negatively affects the mechanical characteristics of the steel substrate.

The development of novel Ti-based amorphous or β-phase nanostructured metallic materials could have significant benefits for implant applications, due to improved corrosion and mechanical characteristics (lower Young’s modulus, better wear performance, improved fracture toughness) in comparison to the standardized α+β titanium alloys. Moreover, the devitrification phenomenon, occurring during heating, could contribute to lower input power during additive manufacturing technologies. Ti-based alloy ribbons were obtained by melt-spinning, considering the ultra-fast cooling rates this method can provide. The titanium alloys contain in various proportions Zr, Nb, and Si (Ti60Zr10Si15Nb15, Ti64Zr10Si15Nb11, Ti56Zr10Si15Nb19) in various proportions. These elements were chosen due to their reported biological safety, as in the case of Zr and Nb, and the metallic glass-forming ability and biocompatibility of Si. The morphology and chemical composition were analyzed by scanning electron microscopy and energy-dispersive X-ray spectroscopy, while the structural features (crystallinity, phase attribution after devitrification (after heat treatment)) were assessed by X-ray diffraction. Some of the mechanical properties (hardness, Young’s modulus) were assessed by instrumented indentation. The thermal stability and crystallization temperatures were measured by differential thermal analysis. High-intensity exothermal peaks were observed during heating of melt-spun ribbons. The corrosion behavior was assessed by electrocorrosion tests. The results show the potential of these alloys to be used as materials for biomedical applications.

Tantalum oxynitride thin films have been deposited by reactive magnetron sputtering, using a fixed proportion reactive gas mixture (85% N2 + 15% O2). To produce the films, the partial pressure of the mixture in the working atmosphere was varied. The characteristics of the produced films were analyzed from three main perspectives and correspondent correlations: the study of the bonding states in the films, the efficiency of photo-degradation, and the antibacterial/antibiofilm capacity of the coatings against Salmonella. X-ray Photoelectron Spectroscopy results suggest that nitride and oxynitride features agree with a constant behavior relative to the tantalum chemistry. The coatings deposited with a higher reactive gas mixture partial pressure exhibit a significantly better antibiofilm capacity. Favorable antibacterial resistance was correlated with the presence of dominant oxynitride contributions. The photocatalytic ability of the deposited films was assessed by measuring the level of degradation of an aqueous solution containing methyl orange, with or without the addition of H2O2, under UV or VIS irradiation. Degradation efficiencies as high as 82% have been obtained, suggesting that tantalum oxynitride films, obtained in certain configurations, are promising materials for the photodegradation of organic pollutants (dyes).