Magnesium-based alloys are promising hydrogen storage materials due to their high capacity but suffer from slow hydrogenation kinetics and high operating temperatures. While high-pressure torsion (HPT) enhances kinetics through microstructural refinement, and nickel addition provides catalytic effects, their combined influence on hydrogen storage performance remains insufficiently characterized. This work investigates Mg-Ni composites with variable Ni content (2–16 at

A series of TiCN-FeCrMo-xNb (x = 2,4,6,8 wt%) was prepared through pressureless vacuum sintering at a sintering temperature of 1500 degrees C. This study aims to fabricate TiCN-high chromium Fe-based cermets and investigate the effect of incorporating strong carbide-forming elements such as Nb on the microstructure, phase, and mechanical properties. The microstructure and composition of the sintered cermets were investigated by Scanning electron microscope (SEM) in combination with an energy dispersive spectrometer (EDS) respectively, and detailed investigation of phase constitution was carried out using thermodynamic calculations and X-ray diffraction (XRD) measurements. Microstructure tends to become finer with increasing Nb additions (up to 4 wt %); however, when Nb additions increase to 6-8 wt%, ceramic particles become much bigger with a bimodal distribution of Ti(C,N) particle size. Microstructure study reveals that the addition of Nb inhibits the grain growth by diffusion of Nb in the Ti(C,N) during solid-state sintering and leads to refining the microstructure. Based on these findings, optimal Nb addition (up to 4 wt%) in the Ti(C,N)-FeCrMo-based cermets plays the role of an inhibitor in the dissolution-reprecipitation process, inhibiting the precipitation of brittle (Ti, M) C, N rim phases. The mechanical properties of the Ti(C,N)-FeCrMo-based cermet increased with 2-4 wt% Nb addition and decreased sharply with further increasing the Nb content. The maximum hardness and fracture toughness have been achieved for the cermet with 4 wt% Nb with 1322 +/- 61 HV30 and 8.56 +/- 0.17 MPa m 1/2 respectively.

The advancement of modern 3D printing technologies has opened the possibilities to fabricate different spectrums of materials using these technologies. Binder jetting 3D printing is a shaping-debinding-sintering-based Additive manufacturing process that selectively fabricates the parts in a layer-by-layer fashion using the local imprinting of polymeric binder. This study aims to develop cobalt and nickel-free TiC-FeCr-based cermets that will contribute to the development of cermets towards green and cost-efficient materials. An effective approach to increase the densities of printed parts was to replace unimodal powder feedstocks with bimodal powders. Therefore, this work employed bimodal spherical powder (TiC and 430L ferritic stainless steel) to promote better densification of the cermet parts. Liquid phase vacuum sintering has been performed with different sintering temperatures to consolidate the cermet parts. Detailed analyses of the microstructure evolution, phase formation, and mechanical properties (hardness and fracture toughness) have been conducted. Further, thermodynamic simulations were conducted to calculate the phase diagram of the proposed cermet using the Thermo-Calc program. Microstructural analysis of consolidated cermets reveals a direct correlation between sintering temperature and carbide grain size, affecting their mechanical and physical properties. The best hardness and fracture toughness properties of TiC-FeCr-based cermets are 1102 +/- 13 HV30 and 12.74 +/- 1.38 MPa m1/2 respectively, were obtained after sintering at 1450 degrees C. Moreover, a systematic comparison is conducted with the same cermet composition fabricated with different additive manufacturing processes based on Laser powder bed fusion and Binder jetting 3D printing technology, demonstrating the potential and limitations of both technologies to fabricate brittle materials such as cermets.

Digitalization and automation are emerging solutions to the complex problems of recycling. In this research work, the experimental and Python based Archard deep learning wear rate models are introduced regarding recycling automation and composite tribological systems optimization. The optimum polyester fibers (PESF) of length of 3-3.5 mm were used for fabrication of polypropylene (PP)-PESF composite systems. The deformation, high texture, asperities, and micro-cracks were observed during scanning electron microscope and machine-learning studies. The lowest experimental value of abrasive wear of 3.0 x 10-6 mm3/Nm was observed for PP. Comparatively, higher experimental values of abrasive wear of the PP-PESF composites are found in the range of 4.35 x 10-6 to 4.7 x 10-6 mm3/Nm due to presence micro-defects on the surface of composites. The experimental values of Coefficient of friction (COF) of PP and PP-PESF are found in the range of 0.70-0.8 and 1.1-1.3, respectively. The experimental values of abrasive wear and COF are found compatible with literature. Similarly, the simulated values of abrasive wear of PP and PP-PESF composites are predicted in the range of 4.8 x 10-7to 3.75 x 10-7mm3/ Nm, respectively. The predicted values of PP and PP-PESF composite show better resistance towards abrasive wear. The proposed experimental and simulated (in terms of Python coding, machine learning, image processing, artificial intelligence, and deep learning studies) research work can be introduced industrially for automation as well as digitalization of grinding of PES waste, processing, tribological testing, and SEM characterization evaluations. (c) 2024 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/ 4.0/).

In engineering education, integrating practical skills with theoretical knowledge is essential for developing competent professionals. This study investigates the benefits of linking Computer Aided Manufacturing and Metal Forming Technologies courses to enhance project-based learning. The primary objective was to assess whether this integration could improve student retention and effectiveness in PBL environments. Using a mixed-methods approach, data were collected from postgraduate mechanical engineering students through surveys, project evaluations, and performance metrics. The integration of these courses resulted in increased student engagement and retention, as well as enhanced quality and innovation in student projects. The findings support the hypothesis that interdisciplinary course integration fosters a more collaborative and engaging learning experience, bridging the gap between theoretical knowledge and practical application. These results align with educational research advocating for experiential and applied learning models, suggesting that such approaches improve retention rates and problem-solving skills, ultimately preparing students more effectively for professional challenges.

Additive manufacturing enables the production of cermet parts encompassing intricate geometries and tailored microstructures. The present study investigates the fabrication of WC-based Ceramic metal composites (CMC) with pure Fe and ferritic stainless steel (AISI Grade 430 L) green binders by controlling melt pool temperature during the Selective laser melting process. A study of crack restraining and formability of WC composite parts with different Fe-based binder compositions has been conducted by adapting Laser beam modulation (LBM). As a result of optimizing the laser beam with variations in laser power peaks (48, 60, and 72 Watt) and constant exposure times for each laser beam profile, the melt pool temperature was regulated, primary cracks in the parts were reduced and this resulted in the fabrication of the parts with reduced process defects such as internal thermal cracks. The reduction in cracks has been attributed to a lower thermal gradient, which has affected the microstructure and microhardness of the as-built parts. Scanning electron microscope (SEM) and X-ray diffraction (XRD) analysis have been used to study the microstructure and phase formation in the fabricated parts. The maximum microhardness (2048 +/- 209 HV1) has been achieved for the fabricated cermets parts with ferritic stainless steel binder with the composition of WC-20 wt% FeCr.

Additive manufacturing (AM), commonly known as 3D printing, has emerged as a transformative technology in the field of manufacturing, offering unprecedented flexibility in creating complex geometries. This study investigates the practical application of AM in producing patterns for investment casting using plaster molds for aluminum components. The primary objective is to identify suitable filament materials for printing patterns that can meet the demands of the casting process while ensuring high-quality aluminum castings. As the process of investment casting in plaster molds involves burning out the pattern, it is important that the burn-out process of the 3D-printed pattern leaves as little residue as possible in the mold. An experimental approach was adopted to evaluate various polylactic acid (PLA) filament materials. Each material was assessed based on the amount of residue remaining after the burn-out process during mold making. The results indicated that some types of PLA filaments behave considerably differently from others. Some filaments leave significantly less residue and can ensure better casting quality. The study provides suggestions for using low-cost filament extrusion-based 3D printers in the plaster mold casting of aluminum products. The findings contribute to the broader adoption of AM in foundry applications by providing insights into material selection and process optimization. Future work will focus on refining the balance between print efficiency and casting quality.

The sustainable processing of polymeric waste is required innovation. In this article, polypropylene (PP)polyethylene terephthalate fiber (PETF) composite materials were fabricated according to the International Organization for Standardization (ISO 9001-2 and 2008) for commercial manufacturing using extrusion and injection molding. The variations of 0, 10, 30, and 40 % of PETF loadings were utilized for mechanical properties' optimization. The results indicate that tensile strength, strain, and young's modulus of elasticity were in the range of 22-25 MPa, 3-5 % and 870-1167 MPa. Correspondingly, the values of flexural strength, strain and modulus constant were in the range of 39-40 MPa, 9-12 % and 1909-2140 MPa, respectively. The impact energies were in the range of 2.6-3.4 kJ/m2. Thermally, the PP-PETF composites were found stable. The scanning electron microscope characterization, presence of induced micro defects, optimum flake structure, analysis of variance, deep learning, and artificial intelligence studies predict the utilization of PP-PETF composites for manufacturing of panels and sheets regarding static loading bearing applications. The reported technical strategies can be utilized as a reference processing technique for industrial manufacturing of PP-PETF based recycled composite products.

In this work, 70 wt% Ti(C,N)- high chromium Fe-based green cermets with the addition of Nb and Ta alloying elements were fabricated through pressureless vacuum sintering. The effects of Ta and Nb addition with varying content on the phase constituents, microstructures, and mechanical properties of the (Ti, Me)(C,N)-FeCr cermets were studied in detail. Cermets with high-chromium ferrous binders face the challenge of the formation of secondary chromium-rich carbides, thus reducing the chromium content of the binding metal. The present work addresses the effect of strong carbide-forming elements, in particular Ta and Nb, on the structure formation of high-chromium Fe-bonded (Ti, Me)(C,N)-FeCr cermets. Using thermodynamic equilibrium calculations, the microstructural investigation was supported by predictions of the compositions of the constituent phases as a function of Ta and Nb additions. The addition of Ta and Nb alloying elements generated (Ti, Me)(C,N) (Me = Ta and Nb) solid solutions and MxCy x C y (M = Fe, Cr) intermediate complex carbide phases during the reaction process, and refined Ti(C,N) particles significantly. The addition of strong carbide-forming elements enables the reduction of chromium depletion in high-chromium (Ti, Me)(C,N)-FeCr cermets. The strengthening mechanisms of (Ti, Me) (C,N)-FeCr cermets were mainly solid solution strengthening, and grain refinement strengthening.

In this study, we evaluated the influence of a new mechanical nanostructuring technique called High Pressure Torsion Extrusion (HPTE) on the microstructural evolution of niobium and the subsequent effects on the mechanical properties and hydrogen storage behaviour. Two different regimes with the extrusion speeds of nu = 7 mm/min and nu = 10 mm/min were implemented in the experiments. A remarkable microstructural refinement and increase in hardness were achieved after one pass of HPTE. The initial grain size of 16.5 mu m decreased to 600 nm and the initial hardness of 80 Hv increased to 284 Hv. Using a Sievert apparatus, it was found that the HPTE processed sample could absorb hydrogen to its full capacity within about 6 h while the as-received sample did not absorb even after one day of exposure to hydrogen gas. Rate limiting step modelling of the hydrogen absorption revealed that the absorption is a 3-dimensional diffusion-controlled reaction with a constant or decreasing interface velocity, depending on the HPTE regime.

Sustainable TiC-Fe-based cermets have been fabricated by adopting an Additive Manufacturing route based on laser powder bed fusion technology (L-PBF). The objective is to produce crack-free cermet components by employing novel multiple laser scanning techniques with variations in laser process parameters. Electron backscatter diffraction analysis (EBSD) was used to study the microstructure and microtexture evolution with variations in laser process parameters. The investigation revealed that adjusting the preheating scan speed (PHS) and melting scan speed (MS) influenced the growth and nucleation of TiC phases. Lowering these speeds resulted in grain coarsening, while higher scan speeds led to grain refinement with larger sub-grain boundaries. Moreover, a high scanning speed increases the degree of dislocation density and internal stress in the fabricated cermet parts. Notably, it is revealed that decreasing the laser scan speed enhanced the proportion of high-angle grain boundaries in the cermet components, signifying an increase in material ductility.

In this study, Ti(C,N)-Fe-based green cermets with different metallic alloying elements have been consolidated by pressureless liquid-phase sintering. The addition of different metallic binders on Ti(C,N)-based cermet such as Nb and Mo on high chromium Ferrous based binder has been investigated. Detailed analysis of the phase constitution was conducted using thermodynamic calculations and experiments, as well as a systematic study of the microstructure evolution and room temperature mechanical properties including hardness and fracture toughness was conducted. The Nb and Mo addition to the binder system affects the sintering temperatures and can significantly affect the phase formation and microstructural development A Scanning electron microscope (SEM) and Energy dispersive spectroscopy (EDS) technique were used to examine the microstructure, composition, and fracture surface of cermets. The addition of the Mo, and Nb reveals lower porosity and finer microstructure as compared to the reference material (Ti(C,N)-Fe-Cr). The refinement of microstructure improves mechanical properties such as hardness and fracture toughness of Ti(C,N)-Fe-Cr-Mo-Nb-based cermets. Further, the addition of these binder elements may reduce the formation of Fe-Cr-based intermetallic complex carbides, allowing cermets to perform better in terms of toughness and corrosion resistance. As a result of the experiments, it is evident that Nb and Mo dissolve in Ti(C,N) and form solid solutions during sintering. The increased number of coreless grains, spinodal decomposition, and crack deflection in cermet further enhance fracture toughness.

We introduce a novel severe plastic deformation process for coarse-grained niobium, which employs a tool with an inclined (wedge) surface for deforming the material by a reverse shear scheme. The process increases the intensity of shear deformations and the depth of plastic deformation in the body of the workpiece when a wedge tool acts on its surface. The essence of the process is in the repeated displacement of the workpiece material in opposite directions during the asymmetrical introduction of a wedge tool until the required degree of deformation is accumulated in the tool-affected volume. This deformation scheme applies a 15 degrees angle wedge tool to a 21-mm high workpiece. After nine cycles of plastic deformation, a gradient of the accumulated degree of deformation in the range of true strain e = 0.3-4.5 was created. At maximum deformation, the microhardness of the workpieces increased by 1.86 times and the tensile strength by 1.6 times. Fractograms show a significant influence of the accumulated degree of deformation on the nature of the fracture. The finite element method simulation of the deformation process showed that creating a uniformly strengthened layer requires at least five deforming operations. For example, the proposed reverse shear process with a wedge tool can be applied to improve the structure of the surface layers of niobium ingots for subsequent forming. Due to the creation of a significant gradient of properties, the reverse shear process can be used as an express method for determining the mechanical characteristics of different materials in a wide range of accumulated degree of deformation.

The present work is a comparative study on the TiC-430 L ferritic stainless steel (FSS) cermets manufactured via two powder metallurgical processes, namely, conventional spark plasma sintering (SPS) and metal additive manufacturing (AM) process (laser powder-bed fusion process (LPBF)/selective laser melting (SLM)). The rescanning strategy has been used to preheat and melt the powder bed with different laser parameters during the SLM process to suppress the presence of residual thermal stress leading to the fabrication of cermets without cracks. The asfabricated SPS samples (95 %) show a relatively lower density than the SLM-built parts (similar to 98 %). A study of their mechanical properties such as hardness, compressive strength, and fracture toughness was conducted and discussed in detail. Further, the corrosion behavior of the fabricated cermets parts was evaluated in 3.5 wt% NaCl. The SLM-prepared specimens reveal finer microstructures and better mechanical properties (compressive strength and fracture toughness) due to the presence of fine microstructure. Furthermore, the corrosion current density of TiC-430 L fss-based cermets fabricated by SLM is approximately 270 times lower than that of cermets parts fabricated by SPS, indicating excellent corrosion resistance. On the other hand, the hardness shows an opposite trend, where the SPS samples show the maximum hardness as compared to the SLM counterparts due to the presence of hard and coarse TiC particles along with some metallic carbides formed during the SPS process. The results reveal that AM processes not only can fabricate cermets with intricate shapes but can also fabricate them with improved mechanical and corrosion properties. (c) 2023 Elsevier B.V. All rights reserved.

In the present study, TiC-Fe cermets were fabricated through selective laser melting (SLM) for the first time employing pulse wave using a pulse shaping technique and regular laser pulse wave. Two samples were fabricated each with adapting pulse shaping technique and regular laser pulse wave with varied laser peak power and exposure time to obtain an optimized parameter. The pulse shaping technique proves to be an optimal method for fabrication of the TiC-Fe-based cermet. The effect of the laser peak power and pulse shaping on the microstructure development was investigated through scanning electron microscopy and X-ray diffraction analysis. Two-phased microstructures revealed the distribution of TiC and Fe. A maximum hardness and fracture toughness of 1010 ± 65 MPa and 16.3 ± 1.7 MPa m1/2, respectively, were observed for the pulsed-shaped samples illustrating that pulse shaping can be an effective way to avoid cracking in brittle materials processed by SLM.

The circularity of polymer waste is an emerging field of research in Europe. In the present research, the thermal, surface, mechanical, and tribological properties of polypropylene (PP)-based composite produced by injection molding were studied. The pure PP matrix was reinforced with 10, 30, and 40% wt. of pure cotton, synthetic polyester, and polyethylene terephthalate post-consumer fibers using a combination of direct extrusion and injection molding techniques. Results indicate that PP-PCPESF-10% wt. exhibits the highest value of tensile strength (29 MPa). However, the values of tensile and flexural strain were lowered with an increase in fiber content due to the presence of micro-defects. Similarly, the values of modulus of elasticity, flexural modulus, flexural strength, and impact energy were enhanced due to an increase in the amount of fiber. The PP-PCCF-40% wt. shows the highest values of flexural constant (2780 MPa) and strength (57 MPa). Additionally, the increase in fiber loadings is directly proportional to the creation of micro-defects, surface roughness, abrasive wear, coefficient of friction, and erosive wear. The lowest average absolute arithmetic surface roughness value (Ra) of PP and PP-PCCF, 10% wt., were 0.19 µm and 0.28 µm. The lowest abrasive wear value of 3.09 × 10−6 mm3/Nm was found for pure PP. The erosive wear value (35 mm3/kg) of PP-PCCF 40% wt. composite material was 2 to 17 times higher than all other composite materials. Finally, the single-step analysis of variance predicts reasonable results in terms of the p-values of each composite material for commercial applications.

The present work deal with the fabrication of TiC-based composites with green Fe-based binder via additive manufacturing such as selective laser melting/laser fusion bed process. The as-built specimen exhibits a bimodal microstructure consisting of fine/ultrafine dendritic and coarser TiC phases. By adopting a novel multiple scan strategy, process defects such as cracks were eliminated by careful control of the melt pool temperature/cooling rates. Even though the mechanical properties may be improved, the anisotropic distribution of the dual phase leads to anisotropic distribution of hardness within the CMC surface.

This article presents an investigation into the impact of High Pressure Torsion Extrusion (HPTE) on the microstructural features, hardness and hydrogen storage, focusing on pure magnesium. HPTE is a modern mechanical nanostructuring technique that can refine the microstructural properties and subsequently affects the mechanical and functional properties of the materials. Two HPTE regimes were used in this study: (1) Direct Extrusion without rotation (DE), and (2) an extrusion speed of 6 mm/min along with a rotational speed of 1.8 rpm (v6w1.8). One sample in as-received conditions was also tested as a reference. Results showed increased hardness in the material after HPTE processing, with the DE sample reaching 60 HRB and the v6w1.8 sample exhibiting a gradient distribution of hardness from 71 to 83 HRB. X-ray diffraction analysis revealed significant microstructural refinement in the v6w1.8 sample. Results of hydrogenation kinetics showed that the DE sample absorbed up to 1.2 wt.% of hydrogen, while the v6w1.8 sample displayed 7.2 wt.% of hydrogen absorption, approaching the theoretical hydrogen storage capacity for magnesium (7.6 wt.%). These findings highlight the positive effects of HPTE on microstructural refinement and hydrogen storage, showcasing its potential for advancements in materials science and hydrogen-based energy technologies.

This article studies the evolution of microstructure and the wear resistance in tantalum processed by a newly developed Severe Plastic Deformation (SPD) technique called Indirect Extrusion Angular Pressing (IEAP). The microstructure and tribological behavior of nanostructured tantalum processed by IEAP were analyzed in this work. The samples were extruded for two, five, and twelve passes of IEAP and then exposed to ball-on-disk wear testing in dry sliding conditions. It was shown that after twelve IEAP passes, an extensive grain refinement down to 500 nm was achieved, hardness increased, and a high dislocation density formed in the material. The wear resistance of the material improved successively after each pass of IEAP, and the wear rate decreased, although the friction coefficient did not change. Evaluation of the morphology of the wear tracks showed that the dominant wear mechanisms were comprised of galling, adhesive wear, pitting and microplowing. Refinement of the microstructure by IEAP led to a reduction in adhesive wear and pitting while a slight increase in oxidation appeared. Comparison of the results of wear testing between tantalum against steel balls and tantalum against alumina balls showed that the presence of alumina generated a larger portion of adhesive wear, making the wear mechanism more complicated while the tantalum-steel pair presented milder wear.

This work aims to develop Co and Ni-free Ti(C,N)-Fe-based cermets which are essential for developing cermets in the direction of green and low-cost materials. TiC and Ti(C,N) -based cermets prove to evince excellent mechanical properties at high temperatures as compared to conventional WC -based cermets. A binder system based on Cr, Mo, Fe, and their alloys may offer a viable solution to replace carcinogen elements such as Ni and Co from the binder. In the present work, high chromium Ti(C,N)-30 wt% FeCrMo cermets were fabricated by using Pressureless liquid-phase sintering. Samples at different sintering temperatures were prepared to investigate the influence of the temperature on microstructural formation and their mechanical characteristics. Scanning Electron Microscopy (SEM) is employed to observe the microstructural formation. A microstructural analysis of the consolidated cermets reveals that the addition of Mo to the binder system and an increase in sintering temperature affect the carbide grain size and densification, which ultimately affect their mechanical characteristics. The hardness and fracture toughness were determined by the Vickers hardness test and Indentation fracture toughness (IFT) method respectively. The maximum Hardness, Fracture toughness, and Transverse rapture strength achieved for the Ti(C,N)-FeCrMo-based green cermets are 665 +/- 6.7 MPa, 1396 +/- 26 HV30, and 9.23 +/- 0.12 MPa m1/2 respectively.