The paper aims to evaluate the outstanding expertise in the Partitioned Weighted Residual Method (PWRM) in addressing the motion of a stretching disk surface in the Bödewadt flow of a radiative hybrid water/Cu+TiO2 nanofluidic model. A hybrid nanofluid is created by mixing copper and titanium dioxide nanomaterials with water. This work examines a closer examination of thermal transmission in the presence of a uniform porous substrate with a convective surface. The classical weighted residual scheme by partitioning is employed to address the transformed governing equations via suitable similarity variables. To evaluate the predictive capability of the Galerkin weighted-residual hybrid, ensuring stable and accurate resolution of the thermo-hydrodynamic interactions, a comparative analysis was conducted between simulation outputs and benchmark numerical data. Outcomes exhibited excellent agreement across tested scenarios. The analysis shows that a retarded Darcy number profiles are observed across radial, axial, and azimuthal momentum directions. The escalation in the angle of inclination prompts the redistribution of the Lorentz force modules acting on the electric conductivity of the hybrid nanofluid, which modifies the momentum balance. It is noted that when the Darcy numbers increase, this leads to a noticeable decrease in the radial stress, while increasing the magnetic factor caused to intensify the radial stress.
Earthen plaster used in traditional buildings often shows powdering, cracking, and debonding during service. This study used pull-off adhesion tests on earthen plaster applied to fired clay brick substrates to evaluate the effects of cement, polyvinyl alcohol (PVA), and straw fibers on adhesion performance. The highest pull-off adhesion strength was recorded for the optimal mix (25 % cement, 1.0 % PVA, 4.5 % straw), achieving 1.15 MPa with a 95 % confidence interval of approximately 1.06–1.24 MPa, indicating improved reliability and performance consistency. This study also developed a data-based installation to present the experimental results in physical form. The installation, titled What Can Soil Be, consists of modular units coated with earthen plaster on fired clay brick. In this work, the mean pull-off adhesion strength was represented by module size, while the confidence interval width (CI w) of the mean result, expressed as CI w, was represented by color and lighting. The installation was exhibited at the Cultural and Art Center of Chiang Mai University from July 17 to 27, 2025. By moving through the installation, viewers could compare differences in strength and CI w through changes in size, surface texture, and light. In this way, the experimental results were presented in a more direct and accessible form.
In this study, we have considered steady-state, incompressible, 2D boundary-layer flow of a Buongiorno nanofluid model over a semi-infinite vertical sheet, examining the combined influence of MHD, thermal radiation, chemical reaction, and velocity slip. The governing equations, derived from the conservation laws of mass, momentum, energy, and species concentration, are reduced to a system of nonlinear ordinary differential equations through the application of non-similarity transformations with the Keller box approach. This reliable finite-difference scheme works well for boundary-layer problems, which accommodate the complexities inherent in the relationships among the variables involved. The impact of many important factors on the velocity, temperature, and concentration profiles of nanoparticles is thoroughly examined. Results reveal that velocity slip significantly reduces the fluid velocity near the wall, while thermal radiation enhances heat transfer rates. Furthermore, chemical reaction effects suppress nanoparticle concentration within the boundary layer. This research presents a novel integration of Buongiorno’s nanofluid model with the combined effects that have not been extensively explored together in prior studies. Additionally, an excellent agreement is achieved when compared with the latest published literature. The findings contribute to a deeper understanding of non-Newtonian fluid behavior and theoretical understanding of nanofluid dynamics over a semi-infinite sheet, and offer guidance for the design of efficient thermal systems and chemical processing technologies.
The present study systematically investigates the influence of coiling temperature (CT, 600–700 °C) on the microstructural evolution and mechanical properties of a high-titanium microalloyed steel (0.37 wt% Ti). The results indicate that the microstructure predominantly consists of ferrite and pearlite under all processing conditions. As the coiling temperature decreases, the ferritic grain size initially refines and then coarsens, reaching a minimum value of approximately 2.5 μm at 650–680 °C. Transmission electron microscopy combined with statistical analysis reveals that the average size of nano-sized TiC precipitates decreases from 75 nm to 54 nm with decreasing CT, accompanied by an increased number density. Mechanical characterization demonstrates that the yield strength generally increases with decreasing CT, reaching a peak value of 841 MPa at 600 °C, while the total elongation peaks at 14.5 % for the specimen coiled at 650 °C. Fractographic analysis indicates a predominant ductile fracture mode for all conditions, albeit with distinct dimple morphologies correlated to the CT. Quantitative decomposition of the strengthening mechanisms unveils that the variation in yield strength is governed by the transition between grain refinement strengthening and precipitation strengthening. The maximum grain refinement strengthening contribution of 362 MPa dominates at 680 °C, whereas the peak precipitation strengthening contribution of 233 MPa becomes predominant at 600 °C. The key novelty of this work lies in the systematic, quantitative decoupling of grain refinement and precipitation strengthening mechanisms as a function of coiling temperature in high-Ti (0.37 wt%) steel. We identify a distinct mechanism transition from grain-refinement dominance at 680 °C to precipitation dominance at 600 °C, elucidating a non-linear strengthening pathway inherent to this high-Ti system. This work establishes a robust process-structure-property framework for high-Ti microalloyed steels, offering a quantitative processing guideline for the development of high-performance seismic-resistant rebars.
Landfilling is a relatively traditional method of waste disposal, yet it remains one of the most widely used approaches for solid waste management. However, landfill generates leachate containing various metal ions including Zn2+ and Ca2+ which affect the anti-seepage performance of liner systems. This study employs physical model tests to investigate the influence of Zn2+ and Ca2+ ions under the hydraulic pressure on the anti-seepage performance of liner systems. The results demonstrate that under the same ionic solution type, leachate hydraulic head is the key factor influencing the anti-seepage performance of sand-bentonite liners where increased of head causing earlier penetration occurrence. The anti-seepage performance of the sand-bentonite liner is significantly reduced. Compared with the deionized water condition (critical head of 5.8 m, initial seepage time of 43 min, and failure time of 68 min), the presence of Zn2+ and Ca2+ reduced the critical hydraulic head for seepage failure to 4.2 m and 4.0 m, decreasing by approximately 16.00 % and 20.00 %, respectively. The initial seepage time was shortened to 1 min and 2.5 min, corresponding to a reduction of 97.67 % and 94.19 %, while the seepage failure time was advanced to 33 min and 9.5 min, with respective decrements of 51.47 % and 86.03 %. However, the anti-seepage performance of the sand–bentonite liner deteriorates significantly under increased leachate heads in the presence of divalent cations such as Zn2+ and Ca2+.
The mechanical properties and damage mechanism of 3D printed carbon fiber reinforced composite laminates were studied. Through the combination of experiment, theoretical analysis and numerical simulation, the mechanical response and failure mode under tensile and three-point bending loads were systematically discussed. The experimental results show that the tensile failure modes of 3D printed carbon fiber reinforced composite laminates are fiber fracture, resin matrix section fracture and fiber pull-out when subjected to tensile load. Under the three-point bending load, the damage gradually expands from the bottom fiber layer to the neutral layer, and the failure modes are matrix crack, interlayer separation and fiber fracture. The tensile strength of the material can reach 46.29 MPa, and the bending strength is 70.13 MPa, the prediction accuracies of maximum tensile load, bending strength and bending modulus are 94 %, 97 % and 97 %. Based on the Hashin failure criterion, a damage model was established to accurately predict the mechanical response and damage mechanism under tension and three-point bending. The results of this study can provide experimental and numerical basis for the design of high-strength lightweight structures, and provide reference for the application of additive manufacturing composites in aerospace, automotive and high-performance engineering structures.
HZO ferroelectric capacitor device have sparked considerable interest among researchers due to their high-speed storage capability and low-power consumption characteristics. Plasma gas interface processing can regulate the oxygen vacancy distribution, improve the interface state and increase the performance and endurance of HZO ferroelectric memories. In this paper, we systematically discuss the effects of the passivation (refers to gas interfacial treatment) process on the ferroelectric properties of ferroelectric capacitors across varying functional layer thicknesses, gas atmospheres, and passivation interface locations. Under different interface processing conditions, the double remanent polarization (2P r ) and endurance of HZO ferroelectric memories could reach up to 39 µC/cm 2 and 10 8 with ferroelectric layer thickness at 10 nm, and the top and bottom interfaces are passivated at the same time used by NH 3 plasma. Furthermore, we propose a two-element (N–H) collaborate mechanism that helps elucidate the independent and synergistic effects of ammonia gas in enhancing the ferroelectric properties of nitrogen and hydrogen at the top and bottom interfaces. This work provided a valuable reference for optimizing the ferroelectric memories components.
To promote the comprehensive utilization of coal gangue, this study employed a direct sintering method to fabricate glass-ceramics using coal gangue as the primary raw material, supplemented by asbestos tailings and copper tailings as additives. The effects of material composition, sintering temperature, and holding time on the physicochemical properties of the ceramics were systematically investigated to determine optimal preparation conditions. Furthermore, the phosphorus adsorption performance of the resulting ceramic was evaluated. The optimal composition was identified as 55 % coal gangue, 35 % asbestos tailings, 5 % copper tailings, and 5 % ammonium bicarbonate. Sintered at 1,200 degrees C for 30 min, the resulting ceramic exhibited a mass loss rate of 37.28 %, a bulk density of 0.16 g/cm3, a water absorption rate of 18.54 %, and a linear expansion rate of 7.89 %, with magnetic intensity remaining below 0.2 mT. Under these optimized conditions, the ceramic demonstrated remarkable phosphorus removal efficiency. Specifically, at an initial pH of 5.0-11.0, a reaction time of 90 min, and a dosage of 10.0 g/L, the phosphorus removal efficiency reached 93.56 %. These findings highlight the significant potential of coal gangue-based ceramics for the treatment of phosphorus-containing wastewater and the valorization of solid waste.
Coating is one of the effective ways to increase the corrosion resistance and wear of metallic substrates. Additionally, the composite coatings using nanoparticles can also further protect the substrate. In this study, using electrodeposition process and polytetrafluoroethylene (PTFE) particles (with concentrations of 10, 20 or 30 g/L), Ni-PTFE coatings were prepared and their corrosion and wear properties were investigated and compared with Ni-P coating. Using scanning electron microscopy (SEM) and X-ray diffraction (EDS) method, the surface morphology and elemental composition of the coatings were analyzed and finally, by using open circuit potential (OCP) techniques, electrochemical impedance spectroscopy (EIS) and TAFEL polarization techniques, the corrosion resistance of the resulting coatings in 3/5 wt% NaCl solution were evaluated. Microhardness and pin on disk tests were also utilized to investigate the effect of PTFE concentration on the tribological properties of the coatings. The results of SEM and EDS studies confirmed the formation of nanocomposites. Electrochemical studies also showed that Ni-PTFE coatings, at a concentration of 20 g/L PTFE, had the highest electrochemical corrosion resistance. Microhardness also decreased with increasing PTFE particles in the coating and reached its lowest value. By using the wear test, the lowest coefficient of friction obtained in composite coatings with concentration of 20 g/L, which shows the applicability of PTFE particles as a solid lubricant in Ni-P coatings.
This study aims to analyze low Reynolds number three-dimensional flow generated by two infinite, rotating as well as stretching disks for a class of non-linear materials governed by the Cross viscosity model, motivated by applications in polymer processing, lubrication systems, coating technologies as well as thermal management of rotating devices. Using a local similarity transformation, the governing equations for the limiting Reynolds flow are reduced to a coupled non-linear system as well as solved numerically via a modified bvp4c scheme, with accuracy confirmed through close agreement with existing results in limiting cases. The influence of key physical parameters including disk stretching, velocity slip, Lorentz forces, thermal radiation as well as Soret as well as Dufour effects on momentum, heat as well as mass transport is quantified. The results show that growing disk stretching parameters significantly enhances axial as well as tangential velocities, while higher slip parameters reduce radial velocity and wall shear stress. Thermal radiation as well as the Dufour number markedly escalate temperature levels and heat transfer rates, whereas the concentration field enhances with the Soret number, indicating stronger mass diffusion. Higher heat transfer rates are observed at the upper rotating disk, while an opposite trend occurs at the lower disk. These findings provide quantitative insight into shear-dependent transport mechanisms as well as demonstrate the significance of the Cross fluid model for optimizing low-cost industrial material processing under low Reynolds number conditions.
The influence of magnesium (Mg) treatment on the inclusions, microstructure, and mechanical properties of hot work die steel (5CrNiMo), a typical low alloy hot working die steel, was investigated in this paper. This steel is commonly used in the manufacturing of large and medium-sized forging dies, as well as various engineering components and mechanical parts. The experimental results show that the Mg treatment has a momentous influence on the refinement of the secondary dendritic arm spacing of as-cast steel samples. The secondary dendrite arm spacing decreased from 66.7 mu m to 39.2 mu m with the Mg content increased from 0.0007 wt% to 0.18 wt%. Furthermore, Mg treatment also contributed to the refinement of the interlamellar spacing of pearlite. The investigation of the quenched microstructure revealed that the Mg treatment led to a reduction in grain size, and the extent of refinement was higher with higher Mg content under the experimental conditions. The tensile properties of the steel exhibited a remarkable improvement due to the refining effect of Mg treatment. In detail, the addition of Mg can increase the tensile strength of the experimental steel from 1,043 MPa to 1,240 MPa and the impact energy from 10.8 J to 15.2 J, with the Mg content increasing from o to 0.069 wt%. A small amount of Mg played a beneficial role in enhancing the strength, plasticity, and toughness of the steel samples. However, excessive Mg content had a detrimental effect on these properties, leading to a decline in strength, plasticity, and toughness.
The increasing discharge of high-salinity industrial wastewater poses serious environmental and resource challenges, necessitating innovative utilization approaches. In this study, high-salt wastewater containing Na+ and Ca2+ ions was employed to prepare coal water slurry (CWS), and its slurrying behavior, stability, and co-combustion characteristics were systematically investigated. Thermogravimetric (TG-DTG) analysis was used to explore combustion performance and reaction kinetics, revealing that elevated salt concentrations weaken slurry stability through double-layer compression but simultaneously enhance combustion reactivity. NaCl promotes combustion throughout all stages, while CaCl2 mainly acts in the middle and later stages due to its stronger polarization and catalytic effects. These findings provide valuable insights into the physicochemical mechanisms governing salt ion-coal interactions and demonstrate the feasibility of harmless and resource-efficient utilization of high-salt concentrated wastewater. The study offers a practical pathway for achieving clean coal utilization and wastewater resource recovery.
High entropy alloy (HEA) coatings deposited via graphene powder mixed Micro EDC process, demonstrates enhanced corrosion resistance of Mg-alloys for implant applications. Utilizing a present process, the HEA coatings have been prepared and conducted detailed analyses of their morphology, corrosion and tribological properties. Present work reveals that (CoCuFeMn)90Ti5Al5 HEA coating substantially impacts corrosion resistance and wear resistance properties. Notably, the (CoCuFeMn)90Ti5Al5 coating was identified as most effective, with a corrosion penetration rate (CPR) of 9.6 mm/year as determined by electro chemical workstation. Further, the tribological properties are also improved by using graphene nano powder during the coating process.
The duel sized silicon carbide (SiC) particles are reinforced A356 metal matrix composite is casted through modified squeeze casting technique by varying SiC percentage viz 1 %-5 % by weight. The tensile strength and hardness were conducted via Universal Testing Machine (UTM) and Brinell hardness testing machine respectively; the dry slide wear behaviour of the samples was analyzed using pin-on-disc test setup. The microstructure of the composite and the wear surface is analysed using scanning electron microscopy (SEM). Sample S5, consisting of 4 % SiC with 80 & micro;m particle size and 1 % SiC with 160 & micro;m particle size, exhibited enhanced properties compared to the as-cast material. The improvement in mechanical strength and hardness can be attributed to the effective densification of the silicon carbide particles within the composite. Tribological performance was evaluated using a Pin-on-Disc apparatus. Tests were carried out by varying load (10 N, 20 N, and 30 N), speed (500 rpm, 750 rpm, and 1,000 rpm), and duration (4, 8, and 12 min) to study their influence on wear rate across various sliding distances. The testing was conducted for sliding length 300 m. SEM image analysis of the worn surfaces revealed intensive adhesive wear behavior. The dual-sized silicon carbide reinforcement (4 % of 80 & micro;m and 1 % of 160 & micro;m) demonstrated superior wear resistance compared to the base alloy. Microstructural examination further indicated minimal delamination, negligible porosity, and the absence of blowholes in the S5 casting. Additionally, the presence of mechanically mixed layers (MMLs) was verified, which was further associated with an increased accumulation of iron within the hybrid composite.
This study investigates the applicability of mechanized Pulsed Gas Metal Arc Welding (m-PGMAW) for the girth welding of API 5L X65 subsea pipelines intended for sour service. Welds were fabricated using ER70S-6 filler wire and augmented process parameters, yielding defect-free joints with a controlled heat-affected zone (HAZ). Hardness mapping confirmed a maximum of 210 HV10, well below the industry standard threshold (250 HV10) for sulfide stress cracking resistance. Tensile testing demonstrated strength matching between weld and base metal, with improved properties at sub-zero temperature (-11 degrees C). Fatigue crack growth rate (FCGR) tests revealed significantly accelerated crack propagation in a sour environment compared to air, attributed to hydrogen embrittlement. The findings provide critical experimental data for Engineering Critical Assessments (ECA), ensuring conservative flaw acceptance criteria and long-term structural integrity of subsea S-lay pipelines operating in aggressive sour environments, and it validates the robustness of the developed m-PGMAW procedure.
Highway tunnels play a vital role in connecting cities and regions. Usually, lining structures with larger permissible deformation is considered a feasible solution to support soft rock tunnels. In this study, an optimized Polyurethane (PU) material was developed by conducting multiple laboratory trials, aiming to achieve a balance between low density, high compressive strength, high tensile strength, and low permeability. Such material is expected to serve as a buffer layer, facilitating stress release in the surrounding rocks and reducing support resistance. The optimized polyurethane is made up of 140:50:50:1.2:0.6:0.8:1.5:2.8 elements, which are composed of polyisocyanate, polyether triol, polyether tetrol, catalyst X, catalyst Y, foaming agent, chain extender, and foam stabilizer. The resulting polyurethane has a density of 145.4 kg/m3, solidifies in 58 s, exhibits a yield strength of 1.38 MPa, a tensile strength of 2.129 MPa, an elongation at break of 12.897 %, and a permeability coefficient of 1.24 & times; 10-5 cm/s. This work partially compensates for the limitations of foam concrete materials and provides an optimized support solution for large deformations in soft rock tunnels.
ZGH451 is a novel age-strengthened nickel-based superalloy renowned for its exceptional toughness and corrosion resistance. However, it is susceptible to cracking during laser powder bed fusion (LPBF) processing. This study systematically investigates LPBF-fabricated ZGH451 to establish the inherent relationship between volumetric energy density (VED) and crack evolution, with particular emphasis on crack initiation and propagation mechanisms. Our findings confirm that optimized VED effectively suppresses cracking. Experimental results reveal that VEDs above 70 J/mm3 induce edge-localized cracks dominated by stress cracks and ductility-dip cracks (DDC), whereas VEDs below 45 J/mm3 produce surface-distributed fine cracks characterized as solidification/liquation cracks. Microstructural analysis demonstrates two distinct mechanisms: excessive VED facilitates high-angle grain boundary cracking, while Al/Ti-based low-melting eutectic phases and Cr/W/Ta/C-derived carbides synergistically enhance grain boundary embrittlement, thereby creating prerequisites for crack nucleation and growth. Moreover, by adjusting the VED from 100 J/mm3 to 49.45 J/mm3, the grain size is refined from 62.43 & micro;m to 35.83 & micro;m, and the grain boundary density is increased by 42.6 %. These improvements significantly reduce stress concentrations and crack formation. This work establishes fundamental correlations between VED and crack behavior in LPBF-processed ZGH451, providing critical guidance for defect mitigation through controlled energy parameters.
The influence of heat treatments between 950 degrees C and 1,150 degrees C on the microstructure evolution in rolled alloy 625 has been studied. Microstructure was characterized by metallography and scanning electron microscopy on samples subjected to different annealing conditions. Significant grain growth occurs in samples heat treated at 1,050 degrees C, attributed to the disappearance of intergranular (Mo,Nb)-rich precipitates. Two samples with different initial microstructural conditions exhibit distinct grain growth behavior. An initially non-uniform microstructure proved difficult to homogenize via subsequent high-temperature heat treatment, even at 1,150 degrees C. Both coarse and fine MC particles exert minimal pinning force on grain growth.
To investigate the gas conversion mechanism in the zero-reforming process of coke oven gas and establish reasonable parameter control ranges, a multi-component multiphase coupled reaction equilibrium system involving CH4 was developed, based on the actual composition of coke oven gas. Thermodynamic analysis of this gas-based shaft furnace multiphase coupling reaction equilibrium system was conducted using the Gibbs free energy minimization method and MATLAB software. Results indicate that during coke oven gas reforming, under conditions of 100-1,100 degrees C and 1-8 atm pressure, adjusting the addition of H2O, CO2, and O2 increases the content of H2 + CO (the effective components of reducing gas), enhances CH4 conversion rate, and controls carbon deposition. The initial H2O amount primarily affects equilibrium H2 concentration, while initial CO2 and O2 amounts primarily affect equilibrium CO concentration. As their addition increases, the concentrations of specific equilibrium components vary. When the reducing gas satisfies H2+CO >= 90 %, CH4 conversion rate >= 90 %, and H2/CO ratio approximate to 8, the optimal additive ranges are: H2O at 4.76-18 %, CO2 at 2.91-18 %, and O2 at 1.71-3.61 %. Simultaneously, initial parameters can be adjusted to meet direct reduced iron production requirements and carbon deposition control. This study provides a theoretical reference for regulating coke oven gas self-reforming to produce hydrogen-rich reduction process gas.
To reinforce Al7075 alloy, this investigation utilized Micro-ZrO2 and Nano-ZrO2 to create in situ titanium diboride particles. Stir casting was used to make this composite. The melt's interior is where the reinforcement particles were produced in situ. 650 degrees C was chosen as the operating temperature for both melting and casting. The study examined the impact of additives containing zirconia oxide on the composite. According to the findings, zirconia oxide reduced the agglomeration of reinforcing particles in the melt. In addition to improving the distribution of reinforcing particles in the composite, cryolite also boosted melt flow and inhibited melt oxidation. Tribological evaluation using pin-on-disc testing showed that ZrO2 reinforcement significantly enhanced wear resistance and reduced the coefficient of friction. Nano-ZrO2 samples exhibited lower wear rates than Micro-ZrO2 due to better dispersion and higher surface area. Because of zirconium, the composite's tensile strength was enhanced, its structure was refined, and the agglomeration of ZrO2 particles was reduced. Furthermore, in samples of wear modified by Zr, the predominant fracture mode. When Nano ZrO2 and Micro were added to the samples, brittle fracture predominated over ductile fracture in ZrO2. The variation range of weight loss among all samples is approximately 0.44 g (from 0.78 g to 0.34 g), indicating significant performance differences.
