Metastable molybdenum (Mo)-based titanium alloys exhibit a low Young’s modulus, along with excellent biocompatibility, corrosion resistance, and mechanical properties, making them ideal for biomedical applications. The microstructure of Ti-Mo alloys can be tailored through thermomechanical processing, where Mo diffusion significantly influences microstructural evolution. To investigate the deformation mechanisms of a Ti-18Mo alloy, hot compression tests were performed using a Gleeble® 3800 in both the α+β- and β-phase regions at temperatures ranging from 610 °C to 910 °C and strain rates between 0.01 s^-1 and 10 s^-1, reaching final strains of 0.50 and 0.80, followed by an immediate water quench. Scanning electron microscopy images and electron backscatter diffraction measurements were used to examine the microstructure of the deformed samples in the α+β- and β-phase regions, respectively. In the β-phase region, the flow curves exhibit a broad work hardening, uncommon in various β-Ti alloys, representing a slowing of dynamic restoration processes, likely due to the influence of Mo on the softening kinetics. Flow curves from α+β-phase deformation show a softening after the peak value, attributed to the globularisation of the α phase. Heterogeneous microstructures were observed during deformation in both regions, indicating that the subgrain formation and α phase globularisation primarily occurred near the previous grain boundaries. Dynamic recovery, dynamic recrystallisation, subgrain size, and α phase globularisation were quantified and correlated with deformation parameters and the influence of Mo.

Nanostructured metals have gained considerable attention in biomedicine due to their superior properties, including enhanced wear resistance, improved biocompatibility, and the ability to interact favorably with human tissues. These materials are highly suitable for applications in the development of bioactive implants, prosthetics, medical devices, and other areas requiring high-performance materials. Compared to traditional metals, nanostructured materials exhibit significantly improved mechanical and chemical behaviors, enhancing their integration into the human body and reducing the risk of rejection or complications post-surgery.

A key advantage of nanostructured metals in biomedicine is their ability to improve biocompatibility by manipulating grain size and structural features at the nanometer scale. This modification enables better interaction with human tissues, minimizing risks such as inflammation or adverse reactions. Furthermore, nanostructuring significantly boosts the mechanical properties of metals, such as tensile strength and durability, making them ideal for prosthetics and implants that must endure substantial mechanical stress over extended periods.

Additionally, nanostructured metals can create bioactive surfaces that promote tissue regeneration or enable the targeted delivery of therapeutic substances. These capabilities make them particularly promising for controlled drug release applications, such as releasing anti-inflammatory or antibiotic agents directly at the site of injury or infection, thereby improving recovery times and preventing post-operative complications.

Nanostructured metals hold great promise for biomedical applications, but challenges remain in large-scale, cost-effective manufacturing and long-term stability in biological environments. Additionally, understanding their long-term effects on human health is an area that requires further research. This paper highlights the benefits, challenges, and limitations of nanostructured metals, while suggesting future research directions to improve manufacturing, performance, and integration in medical devices and implants.

Microbiologically influenced corrosion (MIC) is critical in oil transportation systems, where biofilm formation accelerates metal deterioration, often leading to structural failures and economic losses. Several microbial groups contribute to MIC by interacting with the metal surface or by producing corrosive metabolites that facilitate localized metal loss. In this study, the microbial communities of pigging scrapings and water produced from crude oil and naphtha storage tanks in several oilfields in Colombia were characterized using next-generation sequencing technologies. Additionally, laboratory simulations evaluated MIC and biofilm formation under dynamic and static conditions using native microbial strains. Carbon steel coupons (AISI/SAE 1018) were installed in custom-designed bioreactors, a side-stream system, and exposure setups developed by the Corporación para la Investigación de la Corrosión (CIC). Exposure times ranged from 6 hours to 120 days. Sessile bacterial counts were performed with liquid culture media, complemented by microscopy (SEM) for biofilm characterization and pitting depth determination. Biofilm formation was detected within 12 hours, while sessile SRB colonization occurred at 6 hours. After 90 days, the localized MIC pitting reached 35.5 µm, with a maximum corrosion rate of 5.5 mpy, classified as moderate according to the standard AMPP SP 0775-2023. These findings highlight rapid biofilm development and its correlation with MIC severity under both dynamic and static conditions. The present analysis confirms that the microbial composition associated with production has significant corrosive potential. The presence of these microorganisms and the pitting depths observed indicate a clear MIC threat in such systems. Implementing routine microbiological monitoring, optimizing maintenance schedules, and strengthening internal pipeline cleaning procedures are recommended to the reduce threat of MIC. In the case that MIC materializes in field-installed biocoupons and coupons, biocide treatments should be considered to prevent further structural degradation of oil transportation and storage systems.

One of the key components in the reciprocating lift system and progressive cavity pump system is the steel rod string. This part is in charge of two main objectives in oil production. First, it allows the transmission of movement from surface to downhole, and secondly, it permits fluid lift. Nowadays, the use of continuous rods instead of conventional coupling rod systems has gained considerable attention due to its advantages like the higher amount of annular space available for production, less complex installation, and better distribution of contact loads with tubing. Understanding the reasons for continuous rod failure important to improve the performance and propose improvements in its design, use, and materials. Herein, an extensive data analysis of 51 failures in continuous rods has been performed, providing principal insights to identify the damage mechanisms, and, through fractography analysis, the principal service loads are identified. All the analyzed failures have occurred due to fatigue, implying that fatigue design and assessment are necessary for successful rod performance. Stress concentrators have been caused due to abrasion related to sand management, friction between the tubing and the rod, corrosion (CO₂, microorganisms), issues with rod manufacture quality, operative conditions, installation, and synergies between them. Our results show that the three main reasons for failure are corrosion (31.4%), fretting corrosion (13.4%), and abrasion–corrosion (11.8%) which are related to service conditions, and their principal morphological features were identified. Also, manufacturing rod quality is the source of 9.8% of failures. This provides a useful guide for engineers to find an easy way to identify the reasons for failure in their oilfields. Finally, a comprehensive analysis of the principal used metallurgies is presented, presenting their main advantages, limitations, quality control benchmarks, and future perspectives for new materials in this component.

The significant demand for sustainable and cost-effective energy solutions has led to extensive research into non-noble and earth-abundant metal-based electrocatalysts for energy conversion reactions, such as hydrogen evolution reactions (HERs). While noble metals such as platinum (Pt) and iridium (Ir) have historically dominated due to their exceptional catalytic performance, palladium (Pd) has emerged as a compelling alternative. This is primarily due to its comparatively lower cost, excellent hydrogen adsorption and desorption properties, high catalytic activity, and improved durability. Recent strategies, such as Pd-based alloying with non-noble metals (e.g., Ni, Co, Mo) and nanostructuring techniques, have resulted in enhanced catalytic performance, greater active site exposure, and better stability in alkaline conditions. Herein, cobalt–phosphorus (CoP) and cobalt–iron–phosphorus (CoFeP) coatings were deposited on the copper (Cu) substrate using an electroless deposition method. The incorporation of Pd nanoparticles on the CoP and CoFeP coatings using the galvanic displacement method has been shown to enhance the catalytic activity of the coatings. The morphology, structure, and composition of the catalytic materials were thoroughly examined using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and inductively coupled plasma optical emission spectroscopy (ICP-OES). Moreover, the electrocatalytic activity of the catalysts for the HER in an alkaline solution (1 M KOH) was studied using linear sweep voltammetry (LSV). Electrochemical measurements revealed that PdCoFeP exhibited superior HER activity with a lower overpotential of 180 mV at 10 mA cm⁻² compared to PdCoP due to synergistic effects between Pd, Fe, and Co, which promote efficient charge transfer and reduce the reaction overpotential. This work highlights that Pd-based non-noble metal electrocatalysts have the potential to accelerate the transition towards sustainable hydrogen production, thus contributing to the broader goal of clean and renewable energy technologies.

Acknowledgement

This research was funded by a grant (No. P-MIP-23-467) from the Research Council of Lithuania.

Plasma Electrolytic Oxidation treatment (PEO, which is sometimes also called MAO—Micro Arc Oxidation) has recently attracted a great deal attention due to its ability to create a thick and adherent coating with excellent corrosion and wear resistance. Some of the main characteristics of PEO coatings are the high porosity of the outer layer and the possibility to incorporate directly into the coating particles that are dispersed into the electrolyte. In particular, this last characteristic is particularly useful due to the fact that it permits easy functionalization of the coated surface. The present work describes the results of the production and characterization of PEO-coated samples of aluminum and magnesium alloys obtained by inserting metallic and non-metallic particles into the coating. The coatings are produced with different current modes (direct or pulsed unipolar) and the incorporation occur by simple dispersion of the particles into the electrolyte used for the PEO treatment. Several types of particles were inserted into the coatings: nano-particles of graphite were inserted in order to improve the wear resistance; metallic particles (copper or silver) were inserted in order to give to the samples bactericidal, fungicidal or antifouling properties; glass particles were included to improve the samples' wear and corrosion properties; and titanium dioxide particles were added to create photocatalytic surfaces. The obtained coatings were, in all cases, characterized both on the surface and in the cross-section through SEM analysis and X-Ray diffraction in order to confirm the presence of the particles and to study the microstructure and morphology of the obtained coatings. Later, specific tests were performed to confirm the specific functionality given to the surface (these took the form of corrosion tests, wear tests, biological tests, or photocatalytic tests). In all the cases, the results revealed significant incorporation of the particles into the coating and good specific functional properties.

Thin-walled pure copper tubes, extensively used in high-heat-flux electronic devices due to their excellent thermal conductivity, often develop orange peel defects during bending processes. This study compares tube samples with and without orange peel defects by analyzing their macro-surface morphology and microstructural evolution before and after bending. The crystal plasticity finite element model (CPFEM) was developed to explore the correlation between crystallographic orientation and surface defects. Finally, a multi-scale model of the tube bending process was developed by integrating the macroscopic finite element method (FEM) with the visco-plastic self-consistent (VPSC) approach to simulate and analyze the formation of orange peel defects on the outer wall of the tube at the bending site. The results indicate that high-temperature sintering causes significant grain coarsening and pronounced recrystallization textures in the matrix. Samples exhibiting orange peel defects contain banded annealing twins with textures distinct from the matrix, characterized by low Schmid factors and poor plastic deformation compatibility. CPFEM simulations demonstrate that during uniaxial stretching, "soft-oriented" matrix grains experience negative displacement along the surface normal, forming depressions, whereas "hard-oriented" grains undergo positive displacement, generating protrusions. This mismatch in localized deformation results in the formation of the macroscopic orange peel morphology. Simultaneously, the VPSC simulation results reveal that the number of activated slip variants differs between tubes with and without orange peel defects. Tubes with defects exhibit fewer activated slip variants and experience greater resistance to deformation.

Abstract

With the emergence of data science techniques, such as reduced-order schemes, real-time modeling, machine learning (ML), and smart control schemes, material process modeling and simulations are undergoing a revolutionary phase. Although traditional analytical methods and advanced numerical simulations still provide estimations of multi-physical and multi-scale material processes, generating real-time predictions remains challenging for these techniques. Additionally, data quality and availability issues have slowed the development of data models, while long computational times have hindered the use of advanced numerical simulations for process control. This paper presents the outcomes of research on the simultaneous use of data models and detailed numerical simulations, highlighting their unique roles in control and data generation for future process modeling. While many data processing and handling schemes exist within the data science field, only a few are suitable for material process applications due to their transient and multi-physical natures. As more physics and phases are considered in numerical simulations, the computational time and resources required become enormous, even for today’s parallel and clustered computers. Recently, integrating certain data techniques within numerical simulation frameworks has drastically reduced computational time (e.g., recurrence computational fluid dynamics). This research scrutinizes the efficient use of these simulation techniques for creating fast databases and utilizing these databases for real-time predictions in transient material processes (e.g., casting processes). Consequently, both data models and numerical simulations, along with experimental validations, play crucial roles in generating accurate and reliable metal process modeling. The objective is to integrate these techniques into digital twin and shadow frameworks, driven by industrial digitalization, to enhance greener and more efficient manufacturing. Finally, predefined simulation scenarios were used to produce reliable data models for accurate real-time predictions in metal casting process optimization and control.

The use of binary A15 systems as low-Tc superconductors is of great importance for the development of many modern engineering and technological solutions. As a typical representative of this family, we chose the Nb₃Sn system for our structural studies. Our presentation will focus on two main results: The first is the atomic-scale modeling of Nb chain formation in the condensation of the 3:1 binary combination of Nb and Sn atoms. We will discuss reconstruction in the context of the symmetry of the cubic structure, specifically the transformation of the bcc-type superlattice with Im-3m space symmetry and the crystal phases arising along the Im-3m→Pm-3n symmetry-lowering pathway. We argue that, when Nb and Sn are condensed as Nb₃Sn in the Pm-3n cubic structure, the stabilization of the chains of Nb atoms running parallel to the main cubic axis is caused by their periodic off-center displacements. Change in the point symmetry of the Nb positions is a necessary condition for stable charge ordering. The other effect we will discuss relates to the crystallographic orbits of the Nb sites in the Nb₃Sn Pm-3n lattice geometry. The point symmetry microstructure is caused by the 6c→6d shift in the change of occupation of the 6c Wyckoff positions. Such an occupation shift induces the phenomenon of structural modulation between niobium chain orientations and, thus, defines the bulk structure as composed of subsystems, where the orientation of the niobium chains induces anisotropy caused by the distinct chain patterning in the neighboring lattice regions. Translational symmetry of the Pm-3n space group begins to hold only through the partitioned subsystems. This allows us to predict that the crystallographic equivalence in the point symmetry of Nb sites may be removed when the alloy microstructure is assembled as adjacent grains.

Microbiologically influenced corrosion (MIC) is a phenomenon that contributes to the deterioration of metallic materials in industrial environments. This process has a significant impact on the infrastructure of oilfields, primarily affecting pipelines, storage tanks, and water distribution systems. The main bacterial groups associated with biocorrosion can be classified based on the metabolic pathways they employ. These include sulfate-reducing bacteria (SRB), acid-producing bacteria (APB), and thiosulfate-reducing bacteria (TRB), among others, which colonize and degrade metal surfaces through various metabolic mechanisms. This study aimed to evaluate the efficacy of different biocidal compounds in controlling TRB under laboratory conditions. The modified Time Kill Test (TKT) technique was employed using special BioCIC liquid culture media from the Corporación para la Investigación de la Corrosión (CIC). Seven biocide treatments were tested, including formulations based on tetrakis (hydroxymethyl) phosphonium sulfate (THPS), quaternary ammonium, and glutaraldehyde, among others. Bacterial incubation was conducted at 70°C for 28 days to simulate field conditions. To identify microorganisms associated with biocorrosion in the production water at a Colombian oilfield, total genomic DNA was extracted from the samples and sequenced using the Oxford Nanopore Technology. Among the tested treatments, the M1 formulation (quaternary ammonium 10–30%, THPS 10–30%, and glutaraldehyde 10–30%) exhibited the highest antimicrobial efficacy, significantly reducing bacterial growth compared to the other biocides. The molecular identification of microbial communities in production water samples from seven different field locations revealed Thermotoga and Thermovirga as the predominant genera. However, post-TKT cultures treated with M1 showed a shift in microbial composition, with Acetomicrobium emerging as the dominant genus. These findings highlight the importance of evaluating diverse biocidal formulations to optimize MIC control strategies. Additionally, characterizing microbial populations in production waters is crucial for developing targeted mitigation approaches tailored to the specific microbial consortia present in each field.