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The application of laser melting deposition (LMD) technology for the fabrication of bimetallic composites, specifically TC4-TA15, has been explored. Two distinct bimetallic specimens were successfully synthesized through the sequential deposition of complementary alloy powders onto TC4 and TA15 titanium alloy substrates. The research concentrated on the comprehensive analysis of the specimens’ microstructure, phase composition, interfacial characteristics, and mechanical properties. The results showed that the TA 15/TC4 composites had higher yield strength and ultimate tensile strength compared with the TC4/TA15 materials, with a tensile strength of 1055.38 MPa, which was 19.18% higher than that of the TC4 substrate. And a transition region of about 30 μm wide was observed at the TA 15/TC4 interface, which has a good bonding interface and an improved overall performance.

In this work, non-alloyed Ti/Mg composites were prepared by powder metallurgy, and the strength, ductility and elastic modulus of the composites were enhanced simultaneously. The synergistic effect of Ti content on the microstructure evolution, mechanical properties and deformation behavior of the composite was investigated. The results show that the dynamic recrystallization (DRX) content of the composites increases with the increase of Ti content. Recrystallization causes grain refinement and texture weakening of the composites, which reduces the stress accumulation of the composites. The yield strength, tensile strength and elongation of 10 wt.% Ti/Mg composites reached 195.1 MPa, 300.9 MPa and 14.7%, respectively, which were 42.6%, 57.5% and 11.4% higher than those of Mg matrix. The strength improvement comes from grain refinement, grain boundary pinning and excellent interface bonding. The ductility improvement was attributed to the weakening of texture, the weakening of dislocation density and the synergistic effect of Ti particles.

Al-Mg alloy disks were produced from Mg sandwiched between Al through 100 turns of high-pressure torsion (HPT) at 6.0 GPa at room temperature, resulting in high microhardness of Hv 300–350 in regions experiencing a nominal shear strain >  ~ 390. While compositional mapping using scanning electron microscopy energy-dispersive spectroscopy (EDS) showed a uniform distribution of Mg through the disk thickness at 1.5 mm and 3.0 mm from the disk center, transmission electron microscopy EDS showed a heterogeneous distribution of Mg remained on the nanoscale. Although HPT induces enough mixing to result in face-center-cubic Al with supersaturations of Mg of up to ~ 20 at.% near the disk surfaces, β-Al₃Mg₂, γ-Al₁₂Mg₁₇ and Al₂Mg intermetallic phases were identified by electron diffraction throughout the disk thickness even in regions experiencing high shear strain. This study visually captures detailed compositional heterogeneity throughout the sample thickness following intense mechanical alloying, nanoscale re-structuring and phase transformations.

The valorization of industrial waste is a part of the circular economy strategy of the European Union. The study of the potential mobility of heavy metals has been performed by the BCR sequential procedure. Additionally, the same procedure was applied to the obtained geopolymers to study the level of heavy metal encapsulation in the geopolymer matrix and, correspondingly, the environmental footprint of the newly obtained materials. For verification of the sequential extraction, the BCR procedure and CRM BCR 701 were chosen. In this study, the BCR procedure was modified by lowering the weight of the sample but maintaining the solid-to-liquid ratio, as well as applying different procedures for supernatant separation. ICP-OES measurement was used for determination of Zn, Pb, Cu, Ni, Cd, and Cr in the leachates. The amount of extracted metals in the sequential procedure agreed with the certified values; however, some discrepancies in individual steps were observed. The BCR procedure was applied to fly ash, mine tailings, and geopolymer samples. Different indices were calculated from the BCR data to assess the environmental footprint of the studied materials. A high efficiency of encapsulation in the geopolymer matrix was observed for Cr, Ni, Pb, and Zn. Copper showed increased mobility in the geopolymer samples.

Additive manufacturing (AM) technologies, particularly laser powder bed fusion (LPBF), are revolutionizing the production of complex geometric components. The Ti-5Al-5Mo-5V-3Cr (Ti-5553) alloy, a near-β titanium alloy, is renowned for its exceptional strength, toughness, and high strength-to-weight ratio, making it ideal for fabricating critical aircraft components using LPBF. Despite the advantages of AM, post-machining processes such as drilling are necessary to achieve the tight tolerances and smooth surface finishes required for critical parts. However, the unique machinability characteristics of AM-produced titanium parts present challenges compared to conventionally manufactured counterparts. Although the machinability of cast and wrought titanium alloys is well documented, limited knowledge exists regarding the machinability of AM-produced variants. In this research, Ti-5553 samples were fabricated using LPBF, followed by post-machining under varying drilling parameters. Surface integrity and manufacturability were assessed by characterizing the hole surface microstructure, chemical composition, defects, morphology, roughness, and microhardness, and by evaluating the cutting forces and cutting temperatures. This study demonstrates the manufacturability of LPBF-built Ti-5553 parts and reveals the influence of drilling parameters on surface integrity and manufacturability, providing valuable insights into optimizing machining processes for AM titanium parts and enhancing their use in critical aerospace applications.

The phase equilibria and division of the Ag₂S–GaS–Ga₂S₃–FeS₂–FeS–Ag₂S region (A) of the Ag–Fe–Ga–S system below 600 K were established by the modified EMF method. The electrochemical cells (ECs) of the following structure were assembled: (−)C||Ag||SE||R(Ag⁺)||PE||C(+), where C is the graphite; Ag is the left electrode; SE is the solid-state electrolyte; PE is the right electrode; R(Ag⁺) is the region of Ag⁺ diffusion in the PE. Initially assembled PEs are a nonequilibrium phase mixture of binary sulfides with the ratios of simple substances covering all composition space of (A). The catalyst for the reactions in R(Ag⁺) were Ag⁺ ions acting as small nucleation centers of equilibrium mixtures of compounds. The division of (A) was realized with the participation of the binary as well as more complex compounds AgGaS₂, Ag₉GaS₆, AgFeS₂, Ag₂FeS₂, Ag₂FeGa₂₀S₃₂, Ag₂FeGa₂S₅, and Ag₁₈Fe₉Ga₂S₂₁. The spatial position of the three- and four-phase regions relative to the Ag point was employed to establish the overall potential-forming reactions for synthesizing quaternary phases in the PEs of ECs. The temperature dependencies of the electromotive force of ECs were used to calculate the values of the standard thermodynamic functions of the quaternary compounds.

The wear behavior of the WC-Cu-coated Ti-6Al-4V alloy with composite electrode-assisted electrical discharge coating (EDC) has been studied using the pin-on-disc method. The effect of normal force (10–30 N), sliding speed (16–36 m/s) and sliding time (240–720 s) on the wear rate (WR) and friction coefficient (FC) has been examined. The WR ranged from 0.0002821 to 0.0003880 mm³/N m with a standard deviation of ± 0.00003 mm³/N m, while the friction coefficient ranged from 0.0230 to 0.0454 with a standard deviation of ± 0.003. The results were compared with the uncoated Ti-6Al-4V alloy, showing a significantly higher wear rate of 0.0004500 mm³/N m and friction coefficient of 0.048. The WR and FC both increased with the increasing of normal force and sliding speed, but WR decreased at higher sliding time. In the mild wear region (10 N, 16 m/s, 240 s), grooves and micro-cutting were noticed, while plastic deformation and oxidative wear were identified in the severe wear region (20 N, 26 m/s, 480 s). In the ultra-severe wear region (30 N, 36 m/s, 720 s), the melting of the coating materials caused microcracks and fatigue wear, resulting in increased WR and FC. Compared to conventional coatings, the WC-Cu coating demonstrated improved wear resistance, highlighting its potential for applications in automotive and aerospace industries.

Multiple precision rolling passes are necessary to address issues in twin-roll cast magnesium alloy slabs, such as uneven microstructure, central segregation, and porosity. However, this process can lead to strong basal texture and reduced controllability. To enhance the efficiency of cast-rolled magnesium alloys and highlight the advantages of concise casting and rolling, we conducted comparative evaluations of edge cracking, microstructural consistency, and room-temperature mechanical properties of advanced Mg-Mn-Al-Zn alloys with varying initial thicknesses against the conventional AZ31B alloy. The analysis considers different rolling passes, temperatures, and initial thicknesses. Results indicate that Mg-Mn-Al-Zn alloys exhibit a broader initial rolling temperature range, fewer crack defects, and improved sheet profile and flatness compared to AZ31B. At 300–350°C, Mg-Mn-Al-Zn alloys show enhanced grain refinement and microstructural homogeneity. Both alloys display similar post-rolling tensile properties at room temperature, with approximately 1% variance in peak elongation. Mg-Mn-Al-Zn alloys demonstrate reduced anisotropy compared to AZ31B. With fewer rolling passes, Mg-Mn-Al-Zn alloys slightly outperform AZ31B in mechanical characteristics and ductility. Consequently, Mg-Mn-Al-Zn alloys show improved efficiency in subsequent precision rolling processes compared to traditional cast-rolled AZ31B magnesium alloy, offering potential advantages in industrial applications.

The Idaho National Laboratory (INL) has implemented laboratory-based micro-X-ray computed tomography in a laboratory equipped for the examination of highly radioactive samples. This capability provides nondestructive three-dimensional volumetric information on samples to inform subsequent traditional destructive examinations as well as real-world inputs for high-fidelity scientific modeling. Samples can be imaged with spatial resolutions ranging from several hundred nm/voxel up to ~ 100 µm/voxel. The best usable spatial resolution achieved to date is 384 nm/voxel with this instrument, while the highest radiological dose rate of a sample imaged is ~ 60 R/h β/γ on contact. Advanced data analysis, including custom tomographic reconstruction and segmentation methods, have also been developed to support this capability. In addition to traditional digital X-ray radiography and tomography, this instrument is also able to visualize in situ tensile and compression testing as well as perform diffraction contrast tomography. This work describes the X-ray computed tomography post-irradiation examination capabilities at INL, as well as detailing a variety of applications this instrument has examined.

The accumulation and pollution of copper–nickel smelting slag (CNSS) and other non-ferrous metal smelting slag have become a global issue and focus on the resource utilization of solid waste. CNSS can be used as a substitute for cement to prepare cementitious materials for mine filling, which has the characteristic of effectively immobilizing heavy metal ions. In order to study the feasibility of CNSS for large-scale consumption and utilization in the field of mine filling, cementitious materials were prepared in this study using copper–nickel smelting slag, cement, and palygorskite. The effects of palygorskite addition and curing time on the mechanical properties and microstructure of cementitious materials based on CNSS have been evaluated in detail. The results showed that the addition of palygorskite positively affected the immobilizing of the cementitious materials with the non-ferrous smelting slag by promoting the early hydration reaction. The strength of cementitious materials reached 23.05 MPa when 1% palygorskite, 50% copper–nickel smelting slag, and 49% cement were used, which meet the standards requirements of the mine-filling cementitious materials. The addition of only 1% palygorskite can improve the ability of cementitious materials to immobilize heavy metals and achieve the economic utilization of solid waste in mining areas.