The growing demand for sustainable materials has increased interest in eco-friendly hybrid composites with enhanced mechanical and durability performance. The present study investigates the effect of hygrothermal aging on the mechanical and thermal behavior of palmyra palm leaf stalk/polyester composites with and without chopped strand mat glass fiber reinforcement. The composites were fabricated using the hand lay-up method and exposed to 40 °C and 90% relative humidity for 4 weeks to evaluate their environmental durability. Mechanical performance was assessed through tensile and flexural tests, while thermal, chemical, and morphological changes were analyzed using thermogravimetric analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. The results showed that hygrothermal aging progressively reduced the behavior of both composite systems. The tensile strength of the unreinforced composite decreased by 38.67%, whereas the chopped strand mat-reinforced composite showed a lower reduction of 35.30% after 4 weeks of aging. Similarly, the flexural strength decreased by 31.50% in the unreinforced composite and by 30.87% in the reinforced composite, indicating slightly better flexural retention in the hybrid structure. Thermal analysis revealed a 39.54% reduction in residual weight for the unreinforced composite, while the reinforced composite exhibited only a 15.52% reduction, confirming improved thermal stability. Fourier transform infrared spectroscopy and scanning electron microscopy analyses indicated that the incorporation of chopped strand mat glass fiber outer layers reduced moisture-induced degradation by improving interfacial protection and delaying structural damage. Overall, the hybrid composites exhibited better resistance to hygrothermal aging, demonstrating their potential for lightweight structural applications requiring enhanced environmental durability.
Single point incremental forming has emerged as a promising method for the customized fabrication of titanium biomedical components. However, severe tool–sheet interaction during single point incremental forming can lead to high friction, tool wear, and surface degradation, compromising implant performance and long-term biocompatibility. To address these challenges, this study investigates the tribological behavior and surface topography of commercially pure titanium Grade 2 using different families of nanostructured solid lubricants, including ceramic (ZrO 2 ), polymeric (polytetrafluoroethylene), transition metal dichalcogenide (MoS 2 ), and carbon-based (graphene) lubricants. The lubricants were characterized using scanning electron microscopy and energy-dispersive spectroscopy to confirm their morphology and elemental composition. Tribological performance was evaluated using pin-on-disk tests with titanium Grade 2 as the disk material and tungsten carbide as the counterface pin. The results revealed a clear performance hierarchy among the nanostructured solid lubricants. MoS 2 exhibited the lowest coefficient of friction (0.12) and wear rate (1.6 × 10 −4 mm 3 /N·m), followed by polytetrafluoroethylene (coefficient of friction: 0.15; wear rate: 2.3 × 10 −4 mm 3 /N·m), graphene (coefficient of friction: 0.16; wear rate: 3.4 × 10 −4 mm 3 /N·m), and ZrO 2 showing the highest friction (0.27) and wear rate (3.9 × 10 −4 mm 3 /N·m). Wear track analysis confirmed these trends, with MoS 2 producing the smallest wear track width (549.75 µm) and ZrO 2 the widest (1195.24 µm). Scanning electron microscopy observations indicated distinct wear mechanisms: ZrO 2 promoted abrasive wear, graphene exhibited mixed adhesive and lamellar sliding behavior, polytetrafluoroethylene formed a stable transfer film, and MoS 2 generated a protective lamellar tribofilm. Surface topography analysis of single point incremental forming-formed components showed that MoS 2 produced the best surface finish (Ra = 1.289 µm), followed by polytetrafluoroethylene (Ra = 1.579 µm), graphene (Ra = 2.259 µm), and ZrO 2 (Ra = 4.063 µm). Although MoS 2 exhibited superior tribological performance, polytetrafluoroethylene exhibited stable transfer-film-assisted lubrication, and based on its reported biocompatibility, remains a potential lubricant pending biological validation.
Magnetohydrodynamic flows of ternary hybrid nanofluids have attracted considerable attention owing to their promising applications in advanced thermal management and next-generation high-power electronics cooling. However, despite their superior thermophysical properties, most existing magnetohydrodynamic studies neglect the electric field contribution in the Lorentz force formulation and fail to systematically optimize nanoparticle morphology and volumetric fractions under coupled electric and magnetic fields, leaving a critical thermo-hydraulic research gap. This study aims to optimize ternary hybrid nanofluid thermo-hydraulic performance by incorporating the electric field into the Lorentz force formulation and determining the optimal nanoparticle volumetric fractions. The mathematical model considers steady, incompressible ternary hybrid nanofluid flow through a dynamically altering porous panel under electro-magnetohydrodynamic conditions with thermal radiation. Furthermore, velocity slip, Joule heating, and varying nanoparticle configurations are considered within the boundary layer constraints. The governing differential equations are solved using a hybrid methodology combining the Adomian decomposition method with numerical validation via the Runge–Kutta (RK45) technique. Parametric analyses reveal that nanoparticle morphology and concentration deeply dictate flow dynamics, showing that ternary hybrid nanofluids outperform conventional nanofluids, provided the nanoparticle selection is tailored specifically to either velocity or thermal optimization. Furthermore, increasing electric field intensity boosts flow velocity via boundary-layer propulsion, while enhancing convective heat transfer. This highlights a critical thermo-rheological trade-off, where optimal dynamic performance requires different nanoparticle configurations than thermal enhancement. Ultimately, the proposed electro-magnetohydrodynamics-controlled ternary hybrid nanofluids serve as tunable smart supercooling fluids for energy-efficient engineering applications.
This study numerically investigates entropy generation and uses an artificial neural network (ANN) to predict heat and microorganism transport in hybrid nanofluids (HNFs) containing multiple nanometals with distinct geometries: TiO 2 (blade), Cu (brick), Fe 3 O 4 (cylinder), MoS 2 (platelet), and Ag (spherical), individually combined with spherical Al 2 O 3 nanoparticles in a blood-based medium containing microorganisms flowing between two parallel plates under couple stress and magnetohydrodynamic effects. A novel thermophysical property model is proposed for these HNFs. The governing equations are transformed into dimensionless form and solved using a shooting method coupled with a sixth-order Runge–Kutta scheme. The effects of physical parameters and nanoparticle shapes on velocity, temperature, microorganism concentration, and entropy generation are presented graphically. Results show that TiO 2 + Al 2 O 3 /blood exhibits the highest thermal performance, whereas MoS 2 + Al 2 O 3 /blood shows the lowest. The ANN accurately predicts temperature and microorganism distributions, demonstrating excellent agreement with numerical results. Its performance is evaluated using error histograms, regression analysis, mean squared error, and function-fit analysis. The ANN achieves a regression coefficient of R = 1 and a mean squared error of 4.2863 × 10 −11 , indicating excellent prediction accuracy and convergence. The couple stress parameter ( β ) has the strongest influence on entropy generation, increasing it by 21440.50%, while the Hartmann number (Ha) produces the most significant effect on microorganism concentration, reducing it by 0.448%. These findings have potential applications in biomedical systems, microfluidics, electronic cooling, and enhanced heat-transfer devices.
In this study, Al 5183 wire was deposited on AA6061-T6 substrate using a cold metal transfer (CMT) based wire arc additive manufacturing (WAAM) process. A Taguchi L9 orthogonal array was employed to optimize the welding current and travel speed of robotic welding torch for minimizing dilution while ensuring stable deposition. The novelty of this work lies in the use of a dissimilar material combination and the integration of dilution-oriented process parameter optimization with fractography-based porosity analysis, establishing a direct relationship between microstructure, defects and fracture behavior in WAAM-fabricated aluminum components. The zig-zag path deposition strategy was adopted for optimized condition. Material characterization and mechanical testing were also carried out for the WAAM-deposited sample under optimized parametric conditions. The field emission scanning electron microscopy with energy dispersive X-ray spectroscopy analysis was carried out for the tensile fracture surface. The fractography analysis revealed a ductile fracture characterized by dimples and microvoids. Pore morphology showed that most of the pores were within the 0–1 μm diameter range with circularity values between 0.5 and 0.7, indicating moderately rounded pore geometries. These findings provide practical guidance for process parameter selection to achieve controlled dilution and sound metallurgical bonding in dissimilar CMT-WAAM of aluminum alloys.
Incoloy 825, known for its impressive corrosion resistance, exceptional capability to survive in acidic and chloride environment and mechanical strength, finds extensive application in aerospace, chemical, nuclear, marine and various other industries. Nevertheless, the wide range of application of dry turning in machining Incoloy 825 presents significant challenges, such as toughness, high heat resistance, low thermal conductivity and creep resistance. These issues make the machining of Incoloy 825 a formidable task. In the present investigation, analysing the suitability of advanced cutting tools in dry turning environment by comparison of the result of the uncoated carbide tool, cryo-treated carbide tool and coated carbide tool for various testing parameters such as surface temperature, surface roughness, tool wear and the chip reduction coefficient. A round bar of Incoloy having a diameter of 51 mm and a length of 320 mm was turned at three distinct cutting speeds viz. 51, 76 and 107 m/minute, for cutting intervals of 30, 60, 90 and 120 seconds, respectively. However, the values of the other two machining variables were kept as constant, that is, feed rate = 0.1 mm/rev and depth of cut = 0.5 mm throughout the experiment. The result suggests that the coated and cryo-treated inserts perform better at all predefined cutting speeds as compared to the uncoated counterpart. Coated tool was found to be most favourable as it demonstrated superior results for all the testing parameters except tool wear.
This study investigates magnetohydrodynamic oscillatory Couette-Poiseuille transport of an Oldroyd-B viscoelastic fluid between two infinite parallel plates with velocity slip, thermal radiation, internal heat generation, and periodic pressure forcing. The lower plate oscillates harmonically while the upper plate remains mechanically stationary. For the thermal problem, the lower wall is maintained at the reference temperature and the upper wall is subjected to a small harmonic temperature excitation, which supplies the non-homogeneous thermal forcing required by the analytical solution. The continuity equation is corrected so that the Lorentz force appears only in the momentum balance. Exact harmonic solutions are obtained for velocity, stress, and temperature by the complex-amplitude method. The Rosseland radiation parameter is defined as a positive quantity, and the thermal boundary conditions are made fully consistent with the temperature solution. The results show that slip and fluid elasticity enhance the oscillatory velocity, whereas the magnetic field suppresses motion through Lorentz damping. Increasing the heat-source parameter strengthens the thermal field, while radiation and thermal diffusion modify the wall-temperature gradient and Nusselt number. Joule and viscous heating are not included; therefore, no direct conversion of magnetic damping into thermal energy is claimed. The analytical expressions satisfy the governing ordinary differential equations and boundary conditions identically, and comparison with Ma et al. confirms the limiting hydrodynamic solution.
The treatment of highly concentrated saline brine using reverse osmosis is energy-intensive and poses significant operational challenges due to high osmotic pressure and scaling potential. Solar-powered membrane distillation offers a promising solution for treating concentrated brine in decentralized applications. This study theoretically and experimentally investigates the performance of a parabolic trough collector-powered air gap membrane distillation system for the treatment of highly concentrated saline brine. A theoretical sub-model for the parabolic trough collector and a transport model for the air gap membrane distillation module were developed independently and subsequently coupled to simulate the system performance. Experimental tests were conducted using deionized water to optimize the operating parameters. Based on the optimized parameters, the system performance was further evaluated using real concentrated brine samples with salinity ranging from 10,000 to 50,000 mg/L. The results revealed that at a solar intensity of 950 W/m 2 , the freshwater yield and gain output ratio reached 1.202 kg/h and 0.32, respectively. Freshwater yield and gain output ratio increased with increasing solar intensity and cooling liquid flow rate, while they decreased with increasing feedwater flow rate and air gap thickness. Within the tested operating ranges, the highest system performance was obtained at feedwater flow rate, cooling liquid flow rate, and an air gap thickness of 0.5 kg/min, 4 kg/min, and 10 mm, respectively. Moreover, increasing the feed salinity from 10,000 to 50,000 mg/L reduced the freshwater production and gain output ratio by 47.12% and 27.84%, respectively, at a solar intensity of 900 W/m 2 .
Ferrochrome slag industrial waste and graphene oxide (GO) hybridized Al7075 nanocomposites have tremendous potential for application in the aerospace, defense, marine, and automotive industries. As noted, limited research has been conducted on the machinability and sustainability of squeeze-cast Al7075 hybrid nanocomposites reinforced with 5 wt.% Fe–Cr slag and 0.5%, 1%, or 1.5 wt.% GO. Thus, these have been investigated under sustainable flood-cooling environments in the current research. During flood-cooling machining, VBc ranges of 0.03 to 0.057 mm, Ra from 0.537 to 1.761 µm, T from 39.6°C to 49.9°C, Pc from 0.535 to 0.708 kW, Ce from 0.0044 to 0.0275 kgCO 2 , and Ne from 66.4 to 78.1 dB, all of which are well within the acceptable limits. The 1 wt.% GO nanocomposite shows the most characteristic Raman spectra, with D and G bands at 1347–1349 and 1598–1601 cm −1 , respectively, along with the 2D (∼2703 cm −1 ) and D + G (∼2928 cm −1 ) Raman bands. These features indicate a more effective graphitic structure and tribo-layer formation than those observed for the 0.5 and 1.5 wt.% GO nanocomposites, thereby enhancing machinability. Shorter chip–tool contact length has been observed for the 1 wt.% GO nanocomposite (0.044 and 0.052 mm for Runs 10 and 18), yielding less flank wear than those for 0.5 and 1.5 wt.% GO nanocomposites. The values of circularity and cylindricity are found to be below the tolerance limit of 0.1, indicating good dimensional accuracy, minimal radial deviation, and low form error during the machining of hybrid nanocomposites for precision manufacturing. The optimal parameters are w = 0.9545 wt.%, v = 60 m/min, f = 0.05 mm/rev, and d = 0.1 mm, with a composite desirability of D = 0.9817. The machinability of 1 wt.% GO hybrid nanocomposites is better than that of 0.5 and 1.5 wt.% GO hybrid nanocomposites because of the optimal solid nano lubrication provided by GO at the interface, higher thermal conductivity, and effective coolant penetration into the chip–tool interface zone through substantial reductions sustainability as energy consumption, carbon, and noise emission are substantially reduced.
This study investigates the mechanical properties and failures characteristics of three-dimensional glass laminates that have different contents of graphene nanoparticles. The experimental three-dimensional glass laminates, both without graphene nanoparticles and with 1%, 1.2%, and 2% graphene nanoparticles, were manufactured, and their tensile properties were investigated at different tensile displacement rates of 0.5, 1, and 1.5 mm/minute, respectively. The flexural properties of these samples with different contents of graphene nanoparticles were also evaluated using flexural strength tests. Results indicate that the tensile strength is significantly enhanced when 1% and 1.2% graphene nanoparticles were added. In addition, high displacement loading rates have strongly affected the tensile strength of three-dimensional glass composite laminates. Mixing of nanoparticles and high strain rates has significantly improved the tensile strength. Furthermore, when 1% graphene nanoparticles has been added, the tensile strength increased up to 78%, 77%, and 76% under 0.5, 1, and 1.5 mm/minute displacement rates, respectively. Results show that mixing 1% and 1.2% of graphene nanoparticles with three-dimensional glass laminates can enhance flexural strength by 10% and 2%, respectively, compared to three-dimensional glass fabric composite laminates without nanoparticles. A significant reduction in the flexural strength of these laminates could occur after the addition of 2% graphene nanoparticles.
The use of organic fiber-reinforced polymer composites is growing fast owing to their sustainable, low-density, and eco-friendly nature. The present investigation was carried out to study the mechanical and thermal properties of hybrid epoxy composites reinforced with Murraya koenigii ( M. koenigii) fibers and filled with Syzygium cumini (S. cumini) bio-filler. The composites were prepared by the hand lay-up method with 0, 1, 2, 4, and 6 wt.% S. cumini filler, and the effect of untreated and alkali-treated fibers was studied. Mechanical characterization was carried out by tensile, flexural, impact, and hardness tests (ASTM standards), while thermal behavior was studied by thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The results indicated that composites containing 4 wt.% S. cumini filler showed optimum performance with alkali treatment, due to improved interfacial bonding between the fiber, filler, and epoxy matrix. TGA results showed improved thermal stability, with a higher degradation onset temperature and char yield, while DMA showed a higher storage modulus and a higher glass transition temperature ( T g ). However, the properties decreased when the filler loading exceeded 4 wt.% due to filler agglomeration and poor dispersion. The results showed that the performance of the composites can be significantly improved through fiber treatment and the optimal incorporation of S. cumini bio-filler, making them promising candidates for sustainable lightweight structural and semi-structural applications.
During the operation of new energy vehicles, the pressures of the air springs and the reservoir dynamically change in response to road conditions and vehicle loads. Consequently, the air suspension compressor must operate under variable back-pressures to accommodate pressure variations within the air suspension system. This study focuses on a miniature oil-free piston compressor used in the air suspension system of new energy vehicles, with particular emphasis on its operating states and thermodynamic characteristics under unsteady, variable back-pressure conditions (0.1–1.5 MPa). A combined air suspension compressor-reservoir model was established to analyze the thermodynamic performance and inflation characteristics of the compressor. Furthermore, a test platform was constructed for evaluating the variable back-pressure characteristics of the air suspension compressor, and thermal performance tests were conducted on the prototype. These results showed that under extremely high back pressure, the combined effect of expansion within the clearance volume and external leakage was the primary cause of the reduction in the air suspension compressor inflation. Additionally, at high pressure ratios, expansion and external leakage shifted the peak resistance torque of the compressor motor, causing fluctuations in motor speed and subsequently degrading the air suspension compressor inflation performance. Compared to conventional inflation conditions (0.6 MPa), the volumetric efficiency of the air suspension compressor decreased by 69%, and the isothermal indicated efficiency decreased by 48.1% when the maximum pressure of the air suspension system (1.5 MPa) was reached, leading to a sharp deterioration in air suspension compressor performance. Therefore, better oil-free sealing materials, a more compact clearance volume design, and multi-stage configuration are prospects for adapting to higher operating pressures. This study lays a theoretical foundation for subsequent performance optimization and air suspension compressor design.
Polyethylene terephthalate glycol–carbon fibre composite filaments are widely used in fused deposition modelling because of their good strength, stiffness and dimensional stability. In the present study, polyethylene terephthalate glycol–carbon fibre composite filaments were developed by incorporating carbon fibre into polyethylene terephthalate glycol at different weight percentages of 2.5, 5, 7.5 and 10 wt.%. The developed filaments were subsequently processed using fused deposition modelling to fabricate specimens for systematic evaluation of their mechanical, water absorption and microstructural characteristics. Tensile, compressive and flexural tests were conducted to investigate the influence of carbon fibre content on the mechanical performance of the fabricated composites. The results indicate that the incorporation of carbon fibre significantly influences the tensile, compressive and flexural properties of polyethylene terephthalate glycol. Among the investigated compositions, the 92.5%PETG + 7.5%CF composite exhibited the highest tensile strength of 44.58 MPa and flexural strength of 70.01 MPa, while the 90%PETG + 10%CF composition exhibited the highest compressive strength of 55.85 MPa. Water absorption analysis showed that the 92.5%PETG + 7.5%CF composition exhibited the lowest weight gain of 0.23%. Scanning electron microscopy analysis revealed the influence of fibre dispersion, interfacial bonding, fibre pull-out and localized void formation on the mechanical behaviour. The results show that the developed polyethylene terephthalate glycol–carbon fibre compositions exhibit composition-dependent mechanical and moisture-resistance characteristics, with 92.5%PETG + 7.5%CF providing the best overall balance among the investigated compositions.
Thermal management is essential for improving the efficiency and service life of photovoltaic systems. This study experimentally and numerically investigates a photovoltaic module cooled using an array of aluminum containers filled with lauric acid, an organic phase change material, under transient conditions. The phase change material system reduced the module temperature by up to 10.3 °C, with an average reduction of 8.2 °C, while promoting a more uniform temperature distribution. Over 48 hours, cumulative electricity generation increased by 9.71% compared with an uncooled reference module, corresponding to a net gain of 73.16 Wh. The numerical model closely reproduced the experimental transient response, yielding a mean absolute error of approximately 1.10 °C and a coefficient of determination ( R 2 ) value of 0.975. These results show that integrating phase change material with a suitably designed container array can effectively reduce photovoltaic operating temperatures and improve electrical output.
The inherent microstructural variability, poor surface finish, and dimensional inaccuracies of wire arc additive manufacturing (WAAM)-fabricated Inconel superalloys necessitate effective post-processing to achieve the required functional performance. Therefore, this study quantitatively evaluates the post-processing capability of near-dry electrical discharge machining on WAAM-fabricated Inconel and develops linear regression models. Experiments were conducted using a Taguchi-L9 design with three levels each of three parameters-current, duty cycle, and dielectric flow rate-while material removal rate (MRR), tool wear rate (TWR), and surface roughness were considered as performance variables. All experiments were performed for both copper and brass tool-electrodes, and the resulting response variables were quantitatively compared. The MRR obtained with brass (0.121-3.451 mm³/min) was considerably lower than with copper (0.906-12.34 mm³/min) and showed non-linear behaviour with increased instability at higher discharge currents and duty cycles. Copper consistently exhibited lower TWR, with near-zero or negative wear, while brass ranged from 0.340-5.279 mm³/min. The maximum surface profile height (Rz) ranged from 7-26 μm for brass and 13-41 μm for copper. These results indicate that copper enables high-productivity machining with superior performance, while brass is better suited for finishing applications. Except for the brass TWR model, which showed a lower adjusted R², all regression models were statistically significant and explained a substantial proportion of the variability in MRR, TWR, and Rz. The relatively poor fit of the brass TWR model is attributed to the inherently non-linear relationship between process parameters and TWR, which a simplified linear regression model cannot fully capture.
A physics–data fusion model for tool wear prediction, termed PI-ATBiLSTM, was proposed in the present study to address the limitations of conventional purely data-driven approaches, which do not readily incorporate physical knowledge of the cutting process and depend heavily on large quantities of labelled data. A bidirectional long short-term memory network was integrated with an attention mechanism to capture temporal dependencies and critical wear-related features from the monitoring data obtained from nine identical cutting tools. In addition, a physics-consistent loss function was introduced to embed constraints governing wear evolution into the training process, thereby improving the physical consistency of the predicted wear trajectories. The experimental results showed that, compared with the conventional data-driven model, PI-ATBiLSTM reduced the average root mean square error, mean absolute error and mean absolute percentage error by 60.92%, 60.83% and 62.50%, respectively. Robust predictive performance was maintained under different cutting conditions. The model was further validated on the publicly available PHM2010 dataset, achieving average root mean square error, mean absolute error and mean absolute percentage error values of 1.88 μm, 1.42 μm and 0.014, respectively. Overall, the proposed framework provides an accurate and robust physics–data fusion approach to tool wear prediction for intelligent manufacturing applications.
In this study, the electromagnetic properties of neat and 5 wt.% Cr 2 O 3 -doped aramid/glass fiber hybrid epoxy composites were investigated in the 1–20 GHz frequency range for radome and microwave shielding applications. The complex permittivity, reflection ( S 11 ), and transmission ( S 21 ) behaviors were systematically analyzed with and without metallic backing. Results showed that the real permittivity (ε′) decreased with increasing frequency due to Maxwell–Wagner polarization, while Cr 2 O 3 addition reduced both ε′ and dielectric loss (ε″), indicating lower polarization density. Reflection measurements revealed a pronounced resonance in the 8–10 GHz range, with minimum reflection values of approximately −42 dB for the neat composite and −52 dB for the Cr 2 O 3 -doped composite with metallic backing. Additional resonance minima of about −35 to −37 dB were observed at higher frequencies (17–18 GHz). Transmission results indicated S 21 values of approximately −15 to −30 dB for the neat composite and −15 to −28 dB for the Cr 2 O 3 -doped composite, while metallic backing significantly reduced transmission to −45 to −80 dB, reaching values close to −80 dB in the 15–20 GHz range, corresponding to an additional attenuation of about 20–50 dB. Overall, Cr 2 O 3 primarily influenced dielectric behavior and resonance characteristics, whereas the metallic layer dominated electromagnetic attenuation. The findings indicate that the proposed hybrid composites provide a good balance in terms of electromagnetic performance, making them promising candidates for advanced radome structures. Furthermore, their wide transmission bandwidth and tunable electromagnetic behavior suggest potential applicability as conventional composite core in multifunctional antenna systems.
Inconel X-750 is extensively used in aerospace, nuclear and power generation industries because of its excellent mechanical strength and oxidation resistance at elevated temperatures. However, its high strength, work-hardening tendency and poor thermal conductivity make conventional machining difficult. Laser-assisted turning (LAT) has been widely adopted to improve the machinability of hard-to-cut materials. The influence of machining parameters on cutting temperature and the associated changes in surface and tool morphology during LAT of Inconel X-750 have not been systematically investigated. In this study, LAT experiments were performed on Inconel X-750 using a Taguchi L27 orthogonal array by considering laser power, spindle speed, feed rate and depth of cut (DoC) as the machining variables, with cutting temperature selected as the primary response. The experimental data were analysed using analysis of variance and regression analysis to establish the relationship between machining parameters and cutting temperature. Scanning electron microscopy and microhardness measurements were used to characterize the machined surface and cutting tool. Laser power had the greatest influence on cutting temperature, contributing 84.11%, followed by DoC (6.38%). The regression model showed good agreement with the experimental results, with an R 2 value of 97.57%. The validation test confirmed the model with an accuracy of 94.83%. Moderate cutting temperatures produced more uniform surface morphology, whereas excessive temperatures promoted material smearing, adhesion and diffusion-related changes on the cutting tool. LAT reduced the microhardness because of thermal softening, although the hardness remained above the annealed condition of the alloy.
Additive manufacturing (AM) of titanium alloy is emerging in various aerospace, marine, automobile, and medical implants applications because of high strength-to-weight ratio, enhanced mechanical, biocompatibility, wear, and corrosion resistance properties. AM processes are meant for near-net-shape components with higher mechanical properties due to difference in microstructure and lacks ductility. Optimization of additively manufactured (Amed) process parameters (laser power, scan speed, and layer thickness etc) and post-processing techniques such as stress relief heat treatment and sustainable machining are essentially required to achieve required microstructure, mechanical properties, and surface quality to meet the strict industrial tolerances. Micro-textured tools used with MQL improved the machinability of AMed Ti-6Al-4V reducing chip-tool contact by 38%, feed force by 28.9%, and surface roughness by 10.4% respectively. Reduction of crater wear for cryogenic machining than dry is 58% for direct metal laser sintering and 80% for both heat-treated DMLS and wrought Ti6Al4V alloys. Substantial improvements in drilling performance of Ti-6Al-4V have been observed under hybrid hBN-GNP nanofluids i.e. reductions in energy consumption by 28.8% (wrought) and 24.36% (wire arc additive manufacturing [WAAM]), along with improvement of surface finish by 48.57% and 49.47% respectively. Machining wrought Ti-6Al-4V yields 39.52% higher CO 2 emission than WAAM alloy as revealed from sustainability assessment under nanofluids application. It is worthwhile to analyse machining performance of AMed Ti-6Al-4V under novel sustainable cooling and lubrication environments such as nanofluids as it enhances thermo-physical characteristics and beneficial for sustainable manufacturing. Therefore, this paper reviews the fabrication, characterization, and sustainable machinability aspects of novel additive manufactured Ti-6Al-4V followed by challenges, research gaps, and future scopes.
High-temperature, high-pressure control valves in steam systems experience coupled flow acceleration, heat transfer, pressure loading, and constrained deformation, making repeated structural assessment expensive. A one-way thermal-fluid-structural procedure is established for a normally open control valve, and a POD-RBF reduced-order model is developed to reconstruct the stress field along a measured heat-up and pressurization path. Wall pressure and temperature from the CFD model are transferred to the solid domain, and stress snapshots from six training conditions are aligned on a common reference mesh before modal reduction and radial-basis interpolation. The representative 17.2 MPa/575 °C condition gives a maximum velocity of 15.926 m/second, maximum equivalent stress of 244.96 MPa, and maximum deformation of 0.61765 mm. For the unseen G7 condition, the maximum-stress error is 0.80%. Extreme-condition stress classification identifies the passage transition as the location with the lowest safety margin, although the calculated stresses remain within the allowable limits.
