Beryllium-copper alloys are extensively utilised across various industries due to their excellent mechanical and electrical properties. Beryllium-copper alloys can pose occupational health hazards when manufacturing operations generate airborne beryllium containing dust or fumes. Beryllium free copper alloys such as coppernickel- silicon-chromium (Cu-Ni-Si-Cr) are gaining popularity because they possess comparable properties to traditional beryllium copper alloys while eliminating the health risks associated with this specific exposure source. These non toxic alloys can serve as an alternative to traditional beryllium-copper in various engineering applications. Cu-Ni-Si-Cr alloys are rapidly being researched for application in the advanced materials of renewable energy technologies, die and mould making, electrical devices, electronics components, etc., particularly where thermal conductivity, electrical conductivity, corrosion resistance, and mechanical strength are essential. Electrical discharge machining (EDM) can be effectively utilised in machining hard materials, including beryllium-free copper alloys. The generated surface topography plays a significant role in the majority of applications for these alloys. Therefore, the analysis of the topography of machined surfaces of these alloys is critical. However, research on the EDM of these alloys has been limited. In this study, samples of the berylliumfree copper alloy have been machined using various combinations of input parameters, including the type of electrode, pulse-on time, pulse-off time, and polarity. The generated surface topographies have been analysed using a three dimensional (areal) surface profilometer by considering 23 selected areal surface texture parameters, providing spatial information beyond a single two dimensional roughness profile. These selected geometric indicators are discussed in relation to their potential functional applications. Scanning electron microscopy (SEM) analysis is performed specifically to measure the recast layer thickness of the selected samples below the machined surface. Analysis of variance is used to determine whether the selected input parameters significantly influence the responses. The results of the work show that the obtained Str values exhibit relatively weak directional anisotropy, and the degree of isotropy varying with experimental conditions. Three-dimensional roughness parameters are primarily influenced by polarity and the electrode material. The impact of pulse-off time on surface topography is minimal. Scanning electron microscopy of three selected samples indicates that the observed recast layer thickness increased with surface roughness. It offers a descriptive comparison rather than a generalised statistical correlation. Overall, the results establish a foundational understanding of the EDM induced surface topography and recast layer characteristics of Cu-Ni-Si-Cr alloys for advanced engineering applications.
In this study, 316L-x%WC ([Formula: see text], 3, 5, 8) alloy coatings were fabricated on gray cast iron brake discs using laser cladding technology. The objective was to investigate the influence of the WC ceramic phase on the phase structure, microstructure, microhardness, wear resistance, and corrosion resistance of 316L-based coatings. The results indicate that the coating phases mainly consist of [Formula: see text]-Fe–Ni, Fe 3 C, M[Formula: see text]C 6 , and M 7 C 3 . With the addition of the WC phase, the Cr 3 C 2 phase is introduced into the coating. A sound metallurgical bond is formed between the coating and the substrate. The main matrix of the coating is a carbon-rich [Formula: see text]-Fe–Ni solid solution, presenting as uniform equiaxed grains and columnar grains. Reticulated carbides composed of uniform petal-like and chain-like M[Formula: see text]C 6 , M 7 C 3 , and Fe 3 C act as reinforcing phases distributed between grains and grain boundaries. As the WC content increases, elements Cr and Mo accumulate at the grain boundaries, leading to coarsening of the intergranular phases and refinement of the grains. Under the combined action of strengthening mechanisms such as second-phase strengthening and grain refinement strengthening, the coatings exhibit excellent wear resistance and corrosion resistance. The wear mechanism of the coating is predominantly abrasive wear, which improves coating hardness and wear resistance, reduces wear loss, and provides support for mitigating brake particle emissions.
As critical structural materials for rocket engines, TaW/NbW refractory alloys face severe oxidation issues under high-temperature service conditions, making the development of effective surface protection technologies imperative. This study successfully fabricated Si-Cr-V oxidation-resistant coatings on TaW (Ta12W, Ta10W) and NbW (Nb521, Nb6621) alloys using a slurry sintering method, systematically evaluating the coatings’ static oxidation resistance at 1600°C and 1800°C, along with their thermal shock resistance under air cooling (800 ~ 1800°C) and water quenching (room temperature ~ 1800°C) conditions. The experimental results show that at 1800°C, the effective protection times of the coatings on Ta12W, Ta10W, Nb521, and Nb6621 alloys reached 540, 360, 590, and 535 minutes respectively, while at 1600°C, the protection times for coatings on both Nb521 and Nb6621 alloys extended to 840 minutes. Particularly noteworthy is that the coating on Nb521 alloy withstood 190 thermal cycles under air cooling (800 ~ 1800°C) and endured 341 cycles under water quenching (room temperature ~ 1800°C) without failure. Characterization using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) of the microstructural evolution and elemental distribution during high-temperature oxidation revealed the thermal protection mechanism of the Si-Cr-V coating: metal silicides in the coating undergo oxidative decomposition at high temperatures to form a dense SiO 2 ~ protective layer, which synergistically interacts with multiple metal oxides to establish a protective system, thereby effectively safeguarding the substrate alloy. This study provides an important technical solution for oxidation protection of high-temperature structural materials in aerospace applications, demonstrating significant practical value.
Multilayer metal–ceramic laminates produced through severe plastic deformation have become an effective route for achieving high strength while maintaining reasonable ductility. In this study, Al/Al–TiB 2 layered sheets were manufactured using accumulative roll bonding (ARB) combined with intermediate high-temperature annealing. Al–Zn–Mg–Cu sheets and TiB 2 -modified Al–Zn–Mg–Cu sheets were stacked and rolled through repeated ARB cycles to form multilayer plates. SEM, EBSD, TEM, and EDS analyses showed continuous interfaces with no signs of plastic instability. TiB 2 particles gradually redistributed along the rolling direction, removing clusters and improving strain uniformity. Grain refinement and dynamic recrystallization were evident, and the fraction of high-angle boundaries reached 43.4%. Mechanical tests indicated that the best performance occurred after six ARB cycles, with 540 MPa tensile strength, 417 MPa yield strength, and 14.1% elongation. Strengthening was mainly governed by dislocation accumulation, supported by grain boundary hardening, Orowan bypassing around TiB 2 particles, and minor solid-solution effects. Comparison with earlier ARB systems confirmed that this laminate provides a superior strength–ductility balance. The results emphasize the importance of particle dispersion, recrystallization behavior, and interface stability in controlling the mechanical response of Al-based laminated composites. This work offers practical guidance for designing advanced lightweight laminates for aerospace and transportation applications, showing that ceramic reinforcement combined with ARB processing can eliminate instability and deliver robust mechanical properties.
High-aspect-ratio tubes are central to heat exchange, propulsion and next-generation nuclear systems, yet their inner walls suffer rapid erosion and corrosion that conventional coating processes cannot mitigate uniformly. We report a Rotating Columnar Magnetron Sputtering (RCMS) technique that overcomes the geometric and plasma-transport limits inherent to line-of-sight PVD and high-temperature CVD. A water-cooled cylindrical Ti cathode fitted with a rotating tri-pole Ni–Co magnet array, combined with 20[Formula: see text]mm sacrificial extension tubes, confines a high-density plasma along 120[Formula: see text]mm of 40[Formula: see text]mm-ID stainless-steel tubing. Systematic adjustment of the Ar/N 2 flow ratio (20:1–35:1) reveals an optimum near 25:1 at 2.0[Formula: see text]Pa, which maximizes reactive-gas utilization while preventing target poisoning. Under these conditions, RCMS deposits dense, golden TiN at 1.37[Formula: see text] [Formula: see text]m/h with an axial thickness variation below ± 10% and a hardness of 11 GPa; furthermore, a positive shift in corrosion potential is observed in the coated samples with an increasing Ar/N 2 ratio. X-ray diffraction confirms near-stoichiometric TiN with a face-centered-cubic phase, while SEM cross-sections show a fine columnar morphology devoid of porosity or macroparticles. This combination of uniformity, mechanical integrity, and corrosion resistance demonstrates that RCMS provides a scalable route for the inner-wall protection of critical tubing, making the approach readily adaptable to other refractory or functional ceramics required in aggressive industrial environments.
Magnesium (Mg) alloys, particularly AZ31, are increasingly utilized in the automotive and aviation industries due to their lightweight nature and high strength-to-weight ratio. However, their limited corrosion resistance poses challenges for broader applications. This study addresses this limitation by applying AA2024/Al 2 O 3 cermet coatings on AZ31 Mg alloy using the cold spray (CS) technique. Empirical correlations were developed to predict the corrosion rate and porosity of the coated deposits using response surface methodology (RSM). Analysis of variance (ANOVA) results confirmed the statistical significance of the developed models, with R 2 values of 0.9973 for porosity and 0.9971 for corrosion rate, demonstrating strong predictive accuracy. The effects of key CS process parameters—processing temperature (PT), spray distance of the gun (SDG), and powder feed rate (PFR) —were systematically evaluated. The optimal parameters were determined to be a PT of 530℃, an SDG of 13 mm, and a PFR of 23 g/min, achieving a corrosion rate of 1.29 mm/year (actual) and 1.45 mm/year (predicted), with porosity values of 1 vol.% (actual) and 0.99 vol.% (predicted). Coating characterization revealed enhanced corrosion resistance due to improved deposit density and minimized defects. This work provides a robust framework for optimizing CS process parameters to extend the applicability of Mg alloys in corrosive environments.
In machining processes, a cutting tool must possess suitable contact and thermal properties in addition to mechanical strength. One of the methods to improve the contact properties of the tool is the application of micro-textures on the tool surface. In this paper, inspired by the water supply mechanism of tree leaves, pinnate and palmate bionic micro-textures were created on the tool rake face using a micro-laser process, and their effects on workpiece surface roughness, chip thickness, and tool wear rate were investigated in the turning of AISI 304 stainless steel. Experiments were conducted under oil, water, and soap emulsion coolant conditions at a cutting speed of 250 rpm, feed rate of 0.14 mm/rev, and depth of cut of 0.5 mm. Results demonstrated that the pinnate bionic micro-textured tool, due to better cooling at the tooltip, reduces surface roughness by 30.9%, chip thickness by 8.3%, and tool wear rate by 36.1% compared to the non-textured tool. Scanning electron microscopy (SEM) analysis revealed adhesion as the dominant wear mechanism, with the pinnate-textured tool showing less surface damage. Experimental results showed that the effectiveness of using the leaf vein shape as a micro-texture depends on its geometry. The findings of this study are applicable to manufacturing industries, particularly in the machining of difficult-to-cut materials.
The structural steel 1.0402 is an ideal carbon steel for manufacturing a wide range of general engineering components. In this context, the development of new optimization methods balancing product quality and quantity remains a major concern for industry. In response to this issue, this work investigates the effect of the hardness of a 1.0402 steel workpiece in combination with cutting parameters, namely cutting speed, feed rate, and hole diameter, on machined surface roughness during dry drilling using the Taguchi method. A mixed-level Orthogonal Array (OA) based on the Taguchi design L 18 (2 1 ×3 (3-1) ) was employed. The results showed that the change in the metal structure after heat treatment increased the hardness of 1.0402 steel from 120 Hv to 310 Hv. Regarding machining, the results indicated that surface roughness is mainly influenced by hole diameter, with a contribution of 48.24%, followed by cutting speed and steel hardness, with contributions of 19.76% and 15.18%, respectively, and finally, to a lesser extent, by feed rate, with a contribution of 9.27%. This result is contrary to findings reported in the literature, which generally show that feed rate has the greatest effect on surface quality. In line with industrial requirements, a model was developed to predict surface roughness as a function of drilling parameters, and it achieved a high coefficient of determination of R 2 = 91.2%.
The development of sustainable polymer composites requires natural reinforcements with high cellulose content, improved interfacial compatibility, and enhanced long term mechanical performance. In the present investigation, pineapple fiber and cellulose extracted from Nelumbo nucifera were employed as reinforcements for vinyl ester composites. The cellulose was isolated through sequential alkali treatment followed by high content bleaching to remove residual lignin and hemicellulose, producing highly purified cellulose suitable for composite reinforcement. Subsequently, both the pineapple fiber and the bleached cellulose were subjected to combined alkali and 3 aminopropyltrimethoxysilane (3 APTMS) treatments to improve the reinforcement matrix interface. Composite laminates were fabricated using the hand layup technique with a 0 ° /45 ° /90 ° stacking sequence and evaluated through tensile, flexural, impact, hardness, fatigue, and creep tests, while the fracture behaviour was examined using scanning electron microscopy.The experimental results demonstrated that the synergistic effect of high content cellulose bleaching, combined alkali silane surface modification, and the optimized stacking sequence significantly improved the mechanical and time dependent behaviour of the developed composites. Among the fabricated laminates, MV5, reinforced with 40 vol.% alkali silane treated pineapple fiber and 2 vol.% alkali silane treated bleached cellulose, exhibited the optimum performance, achieving a tensile strength of 186.8 MPa, flexural strength of 163.5 MPa, impact strength of 5.3 J, hardness of 101 Shore D, and fatigue lives of 32,145, 31,567, and 30,824 cycles under 25%, 50%, and 75% of the ultimate tensile strength, respectively. The laminate containing 4 vol.% treated bleached cellulose (MV6) exhibited the highest creep resistance, recording the lowest creep strain values of 0.0038, 0.0191, and 0.0394 after 5000 s, 10,000 s, and 15,000 s, respectively. Fractographic observations confirmed improved reinforcement matrix adhesion, reduced fiber pull out, and delayed crack propagation due to the combined chemical treatments.The findings demonstrate that high content cellulose bleaching, followed by combined alkali silane surface modification and an optimized laminate stacking sequence, provides an effective route for developing lightweight, high performance, and environmentally sustainable vinyl ester composites for automotive, transportation, construction, and other structural engineering applications.
Natural means of product are now gaining attention in recent decades, especially due to their less dense, eco-friendly, cost effective nature. Research are also done on polymer composite material by reinforcing natural sourced fiber filler and bio toughened matrix, to produce bio based compounds without compromising the strength features. The present study investigates the mechanical, wear, flammability properties of naturally derived and surface modified sisal fiber, nanosilica and rice bran oil toughened vinyl ester composite. The composite are developed by manual layup method and test is carried out by ASTM standard. The tensile behavior of the composite VO, by toughening of 15 vol.% of rice bran oil into matrix shows, maximum tensile strength of 44.60 MPa, and it is 100.53% better than plain vinyl ester composite V, while along silane modified fiber (30 vol.%) exhibits better flexural strength of 113.37 MPa (34.8%). In converse, excessive nanosilica content led to a degradation effect on tensile and flexural strength, highlighting the importance of optimal filler loading and dispersion in hybrid composites. Whereas, the impact and hardness strength of composite VS2 (30 vol.% sisal fiber, 15 vol.% bio oil, 10 vol.% nanosilica) exhibited the 3.64 J and hardness strength 77.5 respectively, which provides the better performance in toughness and surface resistance features on the composite. Similarly, the nanosilica-induced surface lubrication and sisal fiber reinforcement on the composite, VS2 had the best wear resistance, with wear loss of 0.013 g and the lowest COF (0.120). When compared to the highly flammable plain vinyl ester (V), all modified composites demonstrated notable improvements in fire resistance; however, VO demonstrated the best flame retardancy with a propagation speed of 13.63 mm/min (V-0 rating, no dripping, and reduced flame speed). Thus, these types of natural fiber, filler, and bio oil reinforcement yield noteworthy outcomes and can be utilized in a variety of fields, including the automobile, infrastructure, and domestic sectors.
Additive manufacturing (AM), specifically three-dimensional (3D) printing, has revolutionized medical implant production by offering unparalleled design versatility and personalization. Titanium alloys are preferred for these implants due to their outstanding mechanical strength, corrosion resistance, and biocompatibility. As implants like hip joints endure constant motion, evaluating their tribological behavior is vital for ensuring long-term performance and reliability. This review summarizes current insights into the tribological (including biocorrosion) characteristics of 3D-printed titanium alloys in biomedical contexts. It explores key factors influencing tribological performance, such as microstructure, surface quality, alloy composition, and printing parameters. A thorough understanding of these factors is critical for rational design and functionality of robust medical implants.
The significant carbon emissions from cement production and the demand for sustainable infrastructure have prompted the development of eco-friendly concrete materials and protective techniques. This research evaluates the durability and environmental performance of Nano-Silicon Dioxide (Nano-SiO2) surface-Treated Green Concrete (GC) incorporating Fly Ash and Silica Fume. Three mixtures, GC-1, GC-2, and GC-3, were prepared using cement moderately exchanged by fly ash (0-100%) and silica fume (0-40%) to decrease ecological effect while sustaining structural performance. A Nano-SiO2-based surface treatment was applied to all surface protection and long-term durability under aggressive environmental conditions. Durability tests, including water absorption, sorptivity, Rapid Chloride Permeability (RCPT), and resistance to acid and sulphate attack, were conducted. Microstructural characterization was performed using X-Ray Diffraction (XRD) to identify hydration products and Field-Emission Scanning Electron Microscopy (FE-SEM) to observe pore structure, cracks, and matrix densification. Environmental performance was assessed through CO2 emission reduction analysis. Among the mixes, GC-3 demonstrated the highest performance. Water absorption was 3.60%, sorptivity 0.085mm/root min, RCPT 1500 coulombs, acid weight loss 3.70%, and sulphate strength loss 4.80%, indicating excellent resistance to moisture ingress and biochemical attack. XRD revealed reduced Calcium Hydroxide (CH) and improved calcium silicate hydrate (C-S-H), confirming enhanced pozzolanic reactions. FE-SEM analysis showed a dense, compact matrix with minimal pores, cracks, and voids. Environmental evaluation indicated a 35% CO2 reduction for GC-3 compared to GC-1. Overall, the combined incorporation of fly ash, silica fume, and Nano-SiO(2 )surface treatment improved durability, microstructural integrity, and environmental performance, providing an effective and sustainable solution for modern concrete structures.
A vacuum-injection-based fabrication method is proposed for producing lightweight sandwich panels for automotive applications. Unlike conventional adhesive bonding, this process forms the face sheets and their connection to the grooved PVC foam core in a single step, reducing manufacturing cost, increasing production speed, and improving interface quality. The sandwich structure consists of a grooved polyvinyl-chloride core and fiberglass/vinyl-ester face sheets, materials commonly used in the automotive industry. Mechanical performance was evaluated under bending and compression loading. The results show that panels fabricated using the proposed method exhibit significantly higher strength than those produced by adhesive bonding. Specifically, bending strength increased by 78% and compressive strength by approximately 40%. This improvement is attributed to the formation of a resin network within the grooves of the PVC core, which enhances core stiffness and strengthens the surface-to-core bond. The novelty of this study lies in introducing a simple reinforcement strategy that substantially improves bending and compressive performance while maintaining low density, offering a lightweight alternative to conventional composite configurations. The resin network created within the grooved core forms a structure analogous to a foam-filled honeycomb, contributing to the enhanced through-thickness mechanical response.
The BiOI/g-C 3 N 4 composites with a sphere-like shape were successfully synthesized via a facile solvothermal method. The morphology, phase and optical properties were characterized by SEM, TEM, XRD and UV–Vis DRS technologies, respectively. Results showed that the BiOI/g-C 3 N 4 composites incorporated a lamellar structure of g-C 3 N 4 and a flower-like structure of BiOI uniformly loaded on the surface of g-C 3 N 4 , which caused the formation of a heterojunction structure for effective separation of charge carriers. Moreover, the photocatalytic degradation performance of as-prepared BiOI/g-C 3 N 4 composites with various ratios was further investigated. Results indicated that the BiOI/g-C 3 N 4 (1:2) composite exhibited wonderful photocatalytic performance in the application of denigrating TC, which could be removed completely under visible light irradiation for 120[Formula: see text]min. The degradation rate of TC still reached 86% after the composite was used five times, which showed excellent stability of the used composite. Results further exhibited that superoxide radical (⋅[Formula: see text]O[Formula: see text]) and hydroxyl radicals (⋅[Formula: see text]OH) were the main active species for photocatalytic degradation of TC, which illustrated a Z-scheme charge transfer mechanism of the BiOI/g-C 3 N 4 composites.
Efficient and sustainable wastewater treatment increasingly depends on microbial consortia capable of simultaneous nutrient removal and biomass recovery. However, conventional systems often suffer from slow microbial aggregation, poor settling characteristics, and limited operational stability, which reduce overall efficiency. To address these limitations, this research investigates the influence of engineered surface hydrophobicity of porous biochar carriers on algae-bacteria granulation in a sequential batch reactor (SBR). Porous biochar derived from agricultural biomass was modified to enhance surface hydrophobicity, thereby improving microbial adhesion and interfacial interactions between microalgae and activated sludge (AS). Selected microalgal species, including Chlorella vulgaris, Scenedesmus obliquus, Nannochloropsis oculata, Phormidium sp., and Arthrospira platensis, were co-cultivated to establish stable algal-bacterial symbiosis. Surface characterization was performed using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and contact angle measurements, confirming improved surface morphology and hydrophobic properties. It was conducted over 45 days, including granule formation (30-35 days) and maturation phases. The process enhanced extracellular polymeric substance (EPS) production, facilitating rapid granulation and biomass retention. Statistical validation and modeling were performed using International Business Machines Statistical Package for the Social Sciences (IBM SPSS) to ensure data reliability. The system achieved 73.3% total nitrogen (TN) removal, 72.5% phosphorus removal, and 77.4% chemical oxygen demand (COD) reduction. Biomass increased from 850mg/L to 5100mg/L, with rapid nitrate removal and improved settling velocity (VS) (5.2m/h). One-way ANOVA assessed group differences in performance (p<0.05). In conclusion, hydrophobic biochar-mediated algae-bacteria granulation provides a scalable and eco-friendly solution for enhanced wastewater treatment performance.
To enhance the high-temperature wear resistance and high-temperature oxidation resistance properties of Ti-6Al-4V, the TiAlNiCrVSiNbx high entropy alloy coating (HEA) was prepared on the Ti-6Al-4V substrate by laser cladding. The effects of Nb on the microstructure and properties of high entropy alloy coatings were mainly studied. The result indicated that the coatings are metallurgically bonded to the substrate. And the coatings consisted of body-centered cubic (BCC), face-centered cubic (FCC) and laves reinforced phases. The high-temperature wear resistance of the TiAlNiCrVSiNb 0.5 HEA coating is 20 times higher than that the Ti-6Al-4V alloy of at 800 ° C. The main wear mechanisms of the TiAlNiCrVSiNb 0.5 coating are oxidative and adhesive wear. After oxidation at 800 ° C for 500 h, the TiAlNiCrVSiNb 0.5 coating exhibited a mass gain of 10.45 mg/cm 2 , which is 1/6 that of under the same conditions. An oxide scale with multi-layer structures consisting of TiO 2 , NiCr 2 O 4 , Al 2 O 3 and VO 2 was generated on the coating. The oxide scale inhibited the inward diffusion of oxygen and the outward diffusion of alloy matrix elements.
Large amounts of chips are inevitably produced during machining of carbon fiber-reinforced polymers (CFRP), which urgently requires further investigation on recycling and high-value utilization. This study focuses on the effects of cutting parameters on chip morphology and chemical reactivity during high-speed turning of CFRP composites. Experimental results show that uniformly fragmented CFRP chips can be obtained at cutting speeds of 404 – 674 m/min, feed rates of 0.1 – 0.25 mm/r, and cutting depths of 0.1 – 0.25 mm. These chips are mainly composed of transparent resin flakes embedded with short carbon fibers. XPS examinations demonstrate that increasing cutting speed, feed rate, and cutting depth significantly promote the mechanochemical degradation of the epoxy matrix. The relative content of C=O increases from 4.51±0.19% to 7.69±0.15%, C-C increases from 59.78±3.10% to 77.10±1.51%, and C-O decreases from 35.71±3.01% to 15.67±1.43%. Cutting speed presents the dominant influence, while the effects of feed rate and cutting depth gradually stabilize beyond a critical threshold. FTIR analysis indicates that the ester C=O content increases greatly with cutting speed, slightly with feed rate, and is barely affected by cutting depth. All three cutting parameters shift the C=O absorption peak toward higher wavenumbers, enhancing the double-bond characteristics and chemical reactivity. A mechanism for the generation of active functional groups in CFRP chips is proposed: mechanochemical reactions occur in the epoxy resin within the primary deformation zone, induced by the coupled effects of high strain rate, mechanical stress, and temperature rise, leading to the breakage of cross-linked molecular chains and the formation of abundant oxygen-containing active groups.
In this study, the flexural behavior of aluminum–epoxy–basalt fiber fiber-metal laminates (FMLs) reinforced with surface-modified and unmodified montmorillonite nanoclay was systematically investigated. Basalt-fiber-reinforced epoxy was used as the core layer between two 2024-T3 aluminum sheets, and nanoclay was incorporated into the epoxy matrix at 0, 1, 3, and 5 wt.% using combined mechanical and ultrasonic dispersion. Three-point bending tests (ASTM D790) were performed to quantify the effects of nanoclay loading on flexural strength, modulus, strain, and fracture energy. The results showed that 3 wt.% of 3-GPTS-modified nanoclay produced the highest improvements, increasing flexural strength by 52%, flexural modulus by 96%, and fracture energy by 195% compared with the unfilled laminate. These enhancements were attributed to improved nanoparticle dispersion, increased matrix stiffness, and stronger interfacial bonding between the epoxy matrix, basalt fibers, and aluminum sheets. At 5 wt.% loading, agglomeration reduced strength and toughness despite further increases in modulus. FESEM analysis confirmed enhanced fiber–matrix adhesion and reduced fiber pullout in the modified nanoclay samples. The findings demonstrate that controlled incorporation of surface-modified nanoclay is an effective strategy for improving the bending performance of basalt-based FMLs, offering potential benefits for lightweight structural applications in aerospace and transportation.
This study investigates the fabrication of St14/Cu10Zn multilayered composites using accumulative roll bonding (ARB) process. The composites were processed through 2, 4, and 6 ARB cycles and evaluated under pin-on-disk wear tests at applied loads of 10, 15, 20, and 25[Formula: see text]N. Microstructural observations revealed progressive layer refinement and thickness reduction with increasing ARB cycles. At the sixth cycle, severe plastic deformation induced necking and shear band formation in the steel layers, leading to their fragmentation and uniform dispersion within the brass matrix. Mechanical results showed a continuous increase in strength from 305[Formula: see text]MPa (St14) and 297[Formula: see text]MPa (brass) in the initial state to 615[Formula: see text]MPa after two cycles and 727[Formula: see text]MPa after 6 cycles, while ductility slightly decreased from 8.5% to 7.6%. Hardness reached 247 HV (steel) and 236 HV (brass) at the sixth cycle. Wear behavior strongly depended on ARB cycles and applied load. At 10 N, the sixth-cycle sample exhibited the lowest wear depth due to higher hardness and refined fragmented structure. At 25 N, wear depths were 60[Formula: see text] [Formula: see text]m (2 cycles), 40[Formula: see text] [Formula: see text]m (4 cycles), and 100[Formula: see text] [Formula: see text]m (6 cycles). The four-cycle composite showed superior wear resistance under higher loads due to stable oxide layer formation and controlled delamination, whereas the sixth-cycle sample exhibited reduced performance because of fragmented steel islands and loss of load-bearing continuity. Wear mechanisms evolved from ploughing, plastic deformation, and cracking in low-cycle conditions to delamination and oxide-assisted wear in higher-cycle states.
Generally, a hybrid Al6061 metal matrix composite has reinforcement with SiC, B 4 C, Alumina, etc. This current research focuses on a hybrid Al6061/SiC/B 4 C Metal Matrix Composite to expose the enhanced mechanical, physical, and wear properties under ageing behavior. The Al6061 matrix is reinforced with SiC and B 4 C, where SiC is varied at 5% and 10% by weight; while B 4 C is kept constant at 3% by weight, fabricated using the liquid metallurgy (stir casting) method. The samples tended to be an age-hardening treatment at 200 ∘ C and 250 ∘ C and solutionized at 550 ∘ C over varying periods. Further, various tests are conducted on the samples as per the ASTM standard in both normal and heat-treated conditions. The hardness distribution curve with peak hardness shows that hardness is affected by a decrease in aging temperature. The peak-aged material’s wear resistance increased at low-temperature aging. The increase in weight percentage of SiC shows an enhanced wear resistance at lower temperatures, and vice versa; the results are obtained while aging at higher temperatures. Age-hardened composites are used in the automotive industry for wheel hubs, cylinder blocks, and cylinder liners.
