Multiscale modelling enabled a systematic investigation of titanium alloy (Ti‐6Al‐4V) single‐lap adhesive joints using Araldite 2015 epoxy reinforced with multi‐walled carbon nanotubes (MWCNTs) and single‐walled boron nitride nanotubes (SWBNTs). A hybrid approach integrates Digi‐mat's nanoscale mean‐field homogenization for predicting effective nanocomposite properties with Abaqus‐based macroscale joint simulations under mechanical loading. Six adhesive configurations are analyzed, neat epoxy, multi‐walled carbon nanotubes‐reinforced (1 wt.‐%–3 wt.‐%), and single‐walled boron nitride nanotubes‐reinforced (1 wt.‐% and 3 wt.‐%). Results demonstrate progressive longitudinal modulus enhancements of 8.69 %, 16.22 %, and 23.89 % for 1 wt.‐%–3 wt.‐% multi‐walled carbon nanotubes, outperforming single‐walled boron nitride nanotubes (8.50 % at 1 wt.‐%, 23.53 % at 3 wt.‐%). The 3 wt.‐% multi‐walled carbon nanotubes adhesive achieved optimal performance, increasing the peel stress concentration by 10% and shear stress localization by 1.2 %, compared to neat epoxy, attributed to improved load transfer and crack resistance. Stress pattern analysis shows that the multi‐walled carbon nanotubes more effectively reduce edge stress singularities, with 3 wt.‐% balancing viscosity limitations and mechanical gains. Single‐walled boron nitride nanotubes exhibit reduced efficiency despite quality modulus gains at 3 wt.‐%, highlighting multi‐walled carbon nanotubes superior reinforcement capacity. These outcomes overview the practicality of 3 wt.‐% multi‐walled carbon nanotubes‐epoxy adhesives for aerospace and automotive industries, offer higher peel strength than neat epoxy while keeping up lightweight characteristics.
Duplex stainless steels are broadly employed in harsh environments because of their excellent combination of mechanical strength and corrosion resistance. But, exposure to temperatures near 475 °C can trigger microstructural degradation within the ferritic phase, which results in development of chromium enriched and Iron enriched nanophases. This transformation is known to cause embrittlement and significantly diminish corrosion resistance, affecting the durability. In this experimental study, the electrochemical performance of duplex stainless steel thermally aged at 475 °C was systematically evaluated, with emphasis on pitting corrosion resistance in both aerated 3.5 weight percent sodium chloride solution and carbon dioxide‐saturated simulated oilfield brines. Electrochemical techniques were used to measure pitting breakdown potentials, while x‐ray photoelectron spectroscopy was employed to characterize the passive film and investigate chloride ion incorporation. Results reveal a significant decline in corrosion resistance associated with thermally induced embrittlement. These outcomes emphasize need of carefully considering thermal exposure effects when deploying duplex stainless‐steel components in service environments prone to aging.
This study employed selective laser melting technology to fabricate four lattice structures (body centered cubic, body centered cubic with simple cubic, face centered cubic, and face centered cubic with simple cubic) of Ti6Al4V, and systematically compared their porosity, phase composition, microstructure, and properties. The research results showed that the actual porosity of all structures was lower than the theoretical design value. All structures primarily consisted of acicular α′ martensite with a small amount of residual β phase. The Body centered cubic structure exhibited the shortest acicular flat noodles and the most uniform microstructure; the Body centered cubic with simple cubic structure had hole defects at the nodes. The Face centered cubic with simple cubic structure exhibited the highest tensile strength, while the Body centered cubic structure had the lowest tensile strength; the Face centered cubic with simple cubic structure had the best compressive properties. The addition of the simple cubic structure suppressed excessive bending of the oblique struts and promoted a partial transition from bending to tensile dominant mechanism, thereby improving the ductility and collapse resistance of the structure; the addition of the simple cubic structure significantly enhanced the impact resistance of the formed parts.
Magnesium alloys are promising candidates for lightweight structural applications; however, their limited hardness and wear resistance restrict wider use, particularly in power train and transmission system components. In this study, friction stir processing (FSP) was employed to improve the surface properties of squeeze‐casted Mg–3Zn alloy. Optical microstructural analysis revealed significant grain refinement in the processed zone, with the average grain size reduced from 55 μm to 6 μm due to dynamic recrystallization. The refined equiaxed grains and increased high‐angle grain boundary density contributed to grain‐boundary strengthening, consistent with the Hall–Petch mechanism, resulting in a 76 % increase in surface microhardness (67 HV to 118 HV). Tribological evaluation under applied loads of 15 N–45 N demonstrated superior wear resistance of the friction stir processed alloy, with a 48.5 % reduction in wear loss at 15 N and lower coefficients of friction compared to the as‐cast alloy. Worn surface analysis indicated abrasion and oxidation at lower loads, while delamination dominated at higher loads. The enhanced tribological performance confirms the suitability of friction stir processed Mg–3Zn alloy for lightweight power train and transmission applications.
Epoxy composites reinforced with pine fibres were fabricated by hand lay‐up at fibre loadings of 4 wt.%, 7 wt.%, 10 wt.%, and 13 wt.%. The fibres were sodium hydroxide (NaOH) treated to enhance interfacial adhesion, and the composites evaluated for mechanical and erosion wear performance. At 10 wt.%, hardness, tensile, flexural, impact, and interlaminar shear strength improved by 18.6 %, 70.5 %, 100.4 %, 89.5 %, and 270.8 %, respectively, over the 4 wt.% composite. Air‐jet erosion was studied using quartz sand (≤75 μm) under steady‐state conditions. Peak erosion occurred at 60°–75° impingement angles, indicating semi‐ductile behaviour; the erosion rate decreased with fibre content up to 10 wt.%. A Taguchi L16‐ANOVA identified fibre content as the most influential parameter, followed by impact velocity, erodent feed rate, and impingement angle, while scanning electron microscopy (SEM) analysis revealed micro‐cracking, cutting, delamination, and plastic deformation. The novelty of this work lies in the combined use of NaOH‐treated Himalayan pine (Pinus roxburghii) needle fibre, a reinforcement seldom examined in erosion studies, together with integated mechanical, dynamic mechanical, and erosion characterisation across fibre loadings, and a Taguchi L16‐ANOVA framework that ranks the factors governing erosive wear and identifies 10 wt.% as the optimum loading.
Magnesium alloys are gaining significant applications in the automobile, aerospace, and biomedical industries due to their high specific strength and low density. However, they are limited by factors such as low ductility and irregular nanoparticle distribution for higher concentrations of reinforcements, hindering their extensive utilization. To address these limitations, this present study investigates the synthesis of ZE43 magnesium alloy‐based hybrid nanocomposites through a novel rotational ultrasonication‐assisted stir casting (RUSC) technique. The multiwall carbon nanotubes (MWCNT) and hexagonal boron nitride (h‐BN) are used as hybrid reinforcements, with 2 weight percentage each. The synergistic effect of rotational stirring and ultrasonication process parameters on hybrid reinforcement dispersion is studied. Statistically, modeling and optimization of the process parameters were done using response surface methodology (RSM), namely, rotational stirring speed, ultrasonication power, and ultrasonication time. The nanocomposites produced were subjected to characterization for the mechanical properties, i.e., microhardness and tensile strength. The optimized parameter showed outstanding improvement in the mechanical properties of the nanocomposites due to efficient nanoparticle dispersion and proper interfacial bonding, which is attributed to the rotational ultrasonication‐assisted stir casting process.
Grinding media consumption accounts for a significant portion of total operational expenses in mineral processing, reaching up to 45 %. This study examines the correlation between microstructure and abrasive wear resistance of metallic alloys under tumbling abrasion, with a focus on practical applications in mineral processing. The novelty lies in establishing systematic links between carbide morphology, matrix hardness, and wear mechanisms in environments of quartz sand and iron ore. Abrasive wear tests were conducted using the SSAB (Swedish Steel AB) tumbling abrasion method, which represents high‐stress wet grinding conditions involving ball–ball and ball–drum collisions, as also defined in previous laboratory ball mill investigations and in more recent analyses of abrasion classification in grinding media. The results show that high‐chromium cast irons exhibit the lowest wear rates (0.18 cm 3 /week), while low‐alloy steels experience up to five times greater volumetric loss (0.91 cm 3 /week). Scanning electron microscopy reveals micro‐grooving and matrix detachment in more complex alloys, whereas softer steels display significant corrosion‐assisted pitting and cracking. These findings provide practical guidelines for alloy design and the selection of grinding media, underscoring the importance of microstructural control in tailoring materials to specific abrasive environments.
Typical non‐conventional routes of severe quenching treatment, both cyclic quenching from room temperature up to 4 cycles and single time quenching from 600 °C after short‐duration (5 min) holding using liquid nitrogen as the quenchant, has been adopted on an initially annealed commercially pure aluminium. The grain refinement effect is observed for single time quenching from 600 °C; but not for cyclic quenching from room temperature. Lattice strain is found to be accumulated up to 2 cycles followed by a decline to a consistent lower value for 3 and 4 cycles in the specimens subjected to cyclic quenching treatment. The specimen, single time quenched from higher temperature (600 °C), exhibits much higher lattice strain as compared to all cyclic quenched specimens. The accumulation of lattice strain is found to be consistent with the evolution of regions of extremely low misorientation angle in the aluminium matrix. As a result of significantly high lattice strain generation and grain refinement effects, the hardness of commercially pure aluminium is substantially enhanced to 88 HV 10 on execution of single time liquid nitrogen quenching from 600 °C after short‐duration (5 min) holding; while compared with an initial hardness of 36 HV 10 in annealed condition.
This study focuses on optimizing tribological process parameters for hybrid metal matrix composites (HMMCs) using the Box‐Behnken method in a response surface methodology (RSM). The hybrid metal matrix composites were fabricated with aluminium alloy 6061 as the base material, reinforced with boron carbide (B 4 C) for enhanced hardness and molybdenum disulfide (MoS 2 ) for self‐lubricating properties. The key tribological parameters considered are normal load (10 N, 25 N, 40 N), sliding speed (0.5 m/s, 1.25 m/s, 2 m/s), and temperature (50 °C, 125 °C, 200 °C). They were systematically varied to analyze their effects on wear rate, using a pin‐on‐disc tribometer. A Box‐Behnken method was employed to evaluate the wear rate with interactions and quadratic effects of the considered tribological parameters. The results indicate that sliding speed and load significantly influence the wear rate while temperature has a secondary but notable effect. Regression models were developed to predict wear behavior, with response surface plots used to visualize interactions. Additionally, scanning electron microscopy (SEM), x‐ray diffraction (XRD) and wear morphology of worn surfaces is studied. This study highlights the potential of the Box‐Behnken methodology in optimizing process parameters with minimal experimental trials while providing detailed insights into material behavior.
The efficiency of the production process of advanced magnetic materials is key to competitiveness and sustainability in modern industry. Advanced magnetic materials are modern materials with enhanced or unique magnetic properties that find applications in cutting‐edge technologies, such as renewable energy sources, electromobility, sensors and electronics. In this way, using the Tecnomatix Plant Simulation software reduces costs, increases product quality, and brings products to market faster while also helping to mitigate the environmental impact of production. The use of this software in the development and optimisation of production processes is currently an increasingly important task. The presented article focused on optimising the production process for 320 compacted 3D samples from advanced magnetic materials, where specific production locations (bottlenecks) were identified and the use of machines and labour was optimised. The research focused on adding value by reducing handling movement and handling times, as well as increasing productionflow.
The effect of a combined addition of boron and niobium on the dynamic recrystallization kinetics of boron‐containing micro‐alloyed low carbon steel has been studied by measuring the flow curves of three different (i.e., niobium, boron‐niobium, boron) micro‐alloyed steels at various temperatures and strain rates and by modeling the recrystallization kinetics in an Avrami expression. The results show that the recrystallization kinetics and flow stress can be modeled in a single function of temperature‐compensated strain‐rate (Z) using Avrami kinetics by applying, not the conventional t 1/2 ‐method, but recently proposed ε 1/2 ‐method. Detailed analysis of the Avrami kinetics together with secondary ion mass spectrometry (SIMS) and drag force calculation show that non‐equilibrium segregation of boron and boron‐niobium complex occurs up to 1100 °C and its intensity increases with the strain rate. The non‐equilibrium segregation decreases both the growth and nucleation rates of dynamic recrystallization by lowering the mobilities of the grain‐ and subgrain‐ boundaries. Combined addition of boron and niobium to boron‐bearing carbon steels leads to more intense segregation on grain‐ and subgrain‐ boundaries, which delays the recrystallization rate more strongly at an early stage but rather accelerates it at an intermediate stage of deformation by forming iron (boron, carbon) (Fe(B, C)) aggregates.
Electronic speckle pattern interferometry is a non‐contact method used to analyze the vibrational modes of mechanical structures. Due to its ability to precisely map deformations and stress in samples made of various materials, it provides a unique insight into the behavior of materials under dynamic loading. This work focuses on the application of electronic speckle pattern interferometry in investigating the vibrational characteristics of composite materials based on polyamide reinforced with carbon fibers in varying weight ratios. The carbon fibers were surface‐modified using nitric acid and silica nanoparticles to increase their surface energy and enhance adhesion to the polymer matrix. These modifications contribute to improved mechanical properties of the composite. Based on the analysis of vibrational modes, key material parameters were determined, namely, the tensile modulus of elasticity, Poisson's ratio, and shear modulus. The obtained vibrational mode results were compared with numerical simulations performed using the Finite Element Method, which allowed for validation of the measurement accuracy and a better understanding of the dynamic behavior of the composites.
Plastic deformation occurring in the forming process during the assembly of thread‐forming screw connections presents a significant challenge for accurate representation in finite element simulations. Among other parameters, the quality of results is largely influenced by the mesh design. With the intention of considering different meshing strategies of the nut component, this study examines the influence of mesh orientation, both straight and parallel to the thread helix, the mesh density, as well as the impact of mass scaling and Arbitrary‐Lagrangian‐Eulerian (ALE) adaptive remeshing operations. The quality of the results obtained was assessed by energy evaluations. Moreover, the size of the nut segment was investigated, revealing that a segment shaped by an angle of 45° around the longitudinal axis is sufficient to accurately represent the forming process and produces similar geometric formations compared to a 360° model. Improvements in results were further achieved by using Arbitrary‐Lagrangian‐Eulerian remeshing operations and a locally refined mesh. Applying mass scaling on highly deformed parts has a large effect on reducing calculation time, simultaneously enlarging element density, which can lead to minor deformation of the nut thread.
The main aim of the article is to create a simulation model that will allow us to study the behaviour of rubber actuator/pneumatic artificial muscles in various dynamic conditions. We investigated a model of a separation device, suitable for branching the material flow in a production line, which uses two pneumatic artificial muscles in antagonistic connection as actuators to drive the semi‐rotary arm. The simulation model was created in the Matlab/Simulink software, while we analysed how changes in various model parameters affect the achievement of the desired final actuator contraction. The work provides important knowledge about the dynamics of rubber actuator and their interaction with various parameters, thereby contributing to a better understanding of their behaviour in technical applications. As a part of the experiment, simple test device equipped with two pneumatic artificial muscles supplemented with a chain transmission to a swing arm was designed.
The article deals with the welding process of a specific part of food machinery and lines – rollers. Rollers come into direct contact with dough and are mainly used to reduce dough thickness. Austenitic chromium‐nickel steel X5CrNi1810 is used for rollers. This steel is characterized by very good corrosion resistance, cold formability and weldability. The roller consists of a tube, two surfaces and a supporting shaft. These individual parts are connected by welds, and the roller acquires its final shape after machining on a lathe. This operation is followed by surface treatment – hard chrome plating and surface grinding to a roughness of Ra 0.8. The welding process is optimized. The KEMPACT PULSE 3000 welding source with a KEMPACTCOOL 10 torch cooling unit is used for welding. Macroscopic observation of welds and hardness tests are carried out. The results of changing welding technology showed significant time savings during welding. The final time after optimizing the welding process is only 14 minutes, a time saving of 27 minutes compared to the old welding process.
Natural fibers such as cotton, hemp, coir, jute, bamboo etc., are available in abundance and are being tried as reinforcements in composites for possible use in transport and structural applications. These composites are gaining attention by researchers because of possessing higher strength, wear resistance, biodegradable nature as well as for the economic considerations. This study focuses on the development and investigation of the mechanical and tribological behavior of jute fiber incorporated in high‐density‐polyethylene/polycarbonate matrices along with carboxylic functionalized multi walled carbon nanotubes. The results revealed that as the high‐density‐polyethylene/polycarbonate proportion in the composites increased from 55/34 to 70/19, the tensile strength, elongation at break and modulus increased by about 27 %, 15 % and 7 %, respectively. In contrast, compressive strength and modulus decreased by 12 % and 11 %, respectively. The slide wear loss decreased with increase in high‐density‐polyethylene content from 55 wt. % to 70 wt. % in the composites, whereas the coefficient of friction increased as the load increased from 20 N to 60 N. The damaged morphological features of the composites tested for tensile and wear properties were examined and characterized using scanning electron microscopy.
The isolation of nanosilica from agricultural waste aims to convert this waste into a valuable material. After the grains are removed, the Sorghum vulgare seed heads are categorized as agricultural biomass waste, serving as an economical source of silica raw material. This study focuses on extracting pure nanosilica from Sorghum vulgare seed heads. The seed heads were calcined at high temperatures to produce ash, and the organic material was eliminated. The resulting ash was subjected to three different chemical treatments: acid (acidification), base (precipitation), and oxidation (oxidizing agent) to remove the inorganic impurities. The isolated nanosilica was characterized using powder x–ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, and energy‐dispersive x–ray spectroscopy. The transmission electron microscopy results indicate that the silica obtained is at the nanoscale. The x–ray diffraction pattern reveals that the silica extracted through the acidification and oxidation process are crystalline in nature, while the silica derived using the precipitation method is amorphous in nature. The Fourier transform infrared spectroscopy spectrum further confirms the presence of silica.
The use of induction heating as an energy source in extrusion‐based metal additive manufacturing is gaining attention for its clean, safe, and precise heating. Melting aluminum filament within the extruder and depositing it can be challenging and requires careful control of temperature distribution which, in turn, depends on current and frequency. This study simulates a 2D axisymmetric model consisting of 8 mm outer radius extruder with 0.9 mm inner radius and induction coil using COMSOL Multiphysics software. The temperature distribution on extruder has been analysed by varying the coil current from 200 A to 300 A in steps, while keeping the frequency constant at 55 kHz. Simulation results show that at 200 A, as the extruder's outer surface reached 650 °C, the inner surface attains 610 °C temperature, which is sufficient to melt aluminum filament required for printing. A 40 °C temperature drop has been observed at the inner surface at 200 A, compared to 68 °C at 250 A and 99 °C at 300 A. Further, experimental validation confirmed the simulation results of less temperature drop at 200 A as compared to other current levels. Hence, this current level is preferred for printing aluminum with the developed setup, offering better thermal uniformity, smooth extrusion of molten materials and consistent layer deposition.
Composite coatings are used in automotive, aerospace, electronics, and manufacturing for their ability to enhance durability, corrosion, and wear resistance in harsh environments. Steel composites with high alumina content show promise but face challenges in adherence and densification. This study investigates the tribological and corrosion properties of alumina/stainless steel 316 composite coatings fabricated using an in‐house developed non‐pneumatic directed energy deposition system. Effect of different alumina/ stainless steel 316 coating compositions on tribological and corrosion behavior of the substrate is evaluated by varying the weight percent of the aluminum oxide (10 %, 20 %, 30 % and 40 %). The coatings exhibit significantly better wear resistance than the substrate, whose friction coefficient is 0.59 ± 0.015. In contrast, coatings I, II, III, and IV show lower values of 0.45 ± 0.007, 0.38 ± .009, 0.35 ± 0.003, and 0.34 ± 0.005, resulting in a continuous decrease in friction and wear. Corrosion resistance improves with higher aluminum oxide content. The self‐corrosion potentials of coatings I, II, III, and IV are −320 ± 10.1 mV, −250 ± 11.2 mV, −220 ± 6.4 mV, and −200 ± 6.3 mV, respectively, which is significantly higher than the substrate (−500 ± 13.65 mV).
This research provides an extensive and sophisticated analysis of debris produced by micro-electrical discharge machining processing of Ni-Ti shape memory alloys and austenitic stainless steel (SS304) using brass electrodes. The research examines how different discharge energy levels controlled by capacitance and voltage affect debris shape and electrode wear and workpiece erosion. The analysis of particle morphology and elemental distribution uses scanning electron microscopy and energy dispersive X-ray spectroscopy. The research shows that irregular debris forms at low energy levels but higher discharge energies lead to spheroidization through localized melting. The analysis shows that debris composition receives material contributions from both the workpiece and electrode sources. The substantial oxidation levels demonstrate how dielectric decomposition affects the process. The research findings directly affect micro-fabrication operations that need both high surface quality and precise dimensional control. Diese Arbeit pr & auml;sentiert eine umfassende und vertiefte Analyse der beim Mikro-Funkenerodieren (Micro-EDM) von Ni-Ti-Formged & auml;chtnislegierungen und austenitischem Edelstahl (SS304) mit Messingelektroden entstehenden Abtragspartikel. Untersucht wird, wie unterschiedliche Entladeenergien, gesteuert & uuml;ber Kapazit & auml;t und Spannung, die Partikelform, den Elektrodenverschlei ss sowie die Werkst & uuml;ckerosion beeinflussen. Zur Analyse der Partikelmorphologie und der Elementverteilung wurden Rasterelektronenmikroskopie und energiedispersive R & ouml;ntgenspektroskopie eingesetzt. Die Ergebnisse zeigen, dass bei niedrigen Entladeenergien unregelm & auml;ss ige Partikel entstehen, w & auml;hrend h & ouml;here Entladeenergien durch lokale Aufschmelzungen zur Sph & auml;roidisierung f & uuml;hren. Weiterhin wurde festgestellt, dass die Partikelzusammensetzung sowohl Materialanteile des Werkst & uuml;cks als auch der Elektrode enth & auml;lt. Die deutlichen Oxidationsanteile belegen den Einfluss der dielektrischen Zersetzung auf den Prozess. Die gewonnenen Erkenntnisse sind unmittelbar relevant f & uuml;r Mikrofertigungstechnologien, die sowohl hohe Oberfl & auml;chenqualit & auml;t als auch pr & auml;zise Ma ss haltigkeit erfordern.
