Iranian Journal of Materials Science and Engineering

Synthesis and Photocatalytic Properties of Sol-Gel Derived B₂O₃-SiO₂-TiO₂ Glass-Ceramic Coatings

Sara Ahmadi

The crystallization behavior and photocatalytic properties of the sol-gel derived glass ceramic coatings in the TiO₂-SiO₂-B₂O₃ system were studied. the prepared sol was sprayed on a glazed ceramic wall. Following drying, the coated specimens were fired at 900°C for 1 h. The impact of boron oxide content in the composition was explored in terms of anatase stability and glass maturing temperature. The thermal and crystallization behaviors of the dried gels were studied by the STA, XRD, and FESEM. The photocatalytic property of the coated layer was examined using methylen blue degradation. Based on the results, the sample containing 15 wt% of boron oxide demonestrated about 30% dye removal efficiency, after only 60 min of UV-irradiation. Additionally, this particular sample exhibited the greatest magnitude of the anatase phase in comparison to the other samples.

Effect of Current Type and Particle Size on Wear and Corrosion Behaviour of Electroplated Ni-B4C Composite Coatings

Behnam Lotfi

Ni-B₄C nanocomposite coatings were deposited onto a pure Cu substrate using electroplating. Different types of current, including direct current (DC), pulse reverse current (PRC), and unipolar pulse current (PC), were applied using various concentrations of micron and nano size particles in the electroplating bath. Microstructure, hardness, and wear and corrosion behavior of the coatings were investigated. Microstructural evaluations were performed using scanning electron microscopy (SEM) and field emission scanning electron microscopy (FESEM). Microhardness, pin-on-disk sliding wear, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) tests were conducted on the coatings. Electrodeposition using PRC resulted in a more uniform distribution of co-deposited B₄C microparticles and nanoparticles within the coatings. Nanocomposite coatings reinforced with B₄C nanoparticles were obtained using PRC with a bath concentration of 8 g/l, exhibited higher hardness and improved wear properties compared to composite coatings containing B₄C micron-sized particles. Moreover, using PRC resulted in higher hardness values and improved wear and corrosion resistance compared to PC and DC.

Effect of Selective Laser Melting Fabrication Parameters and Heat Treatment on the Microstructure and Mechanical Properties of Maraging 300 Alloy

Yaser Vahidshad

Selective laser melting (SLM) is a widely used additive manufacturing method for 3D-printing metal parts. This study investigates how SLM parameters affect the density, microstructure, and mechanical properties of maraging steel 300. A process window was developed, revealing that maximum density and minimal porosity are achieved when laser energy density exceeds 50 J/mm³. Optimal parameters—100 mm/s scan speed, 20 μm layer thickness, 0.15 mm hatch distance, Stripe scanning strategy, and XZ build direction—were identified. Optimal processing reduced porosity, increased martensite content, and enhanced strength, reaching 1064 MPa and improving by 75% to 1862 MPa after aging and solution treatment. Strength gains were attributed to the uniform dispersion of nano-sized precipitates (such as Ni(Mo)₃ and Ni(Ti, Al)₃) within the martensitic matrix. Additionally, it was found that higher cooling rates further improve the mechanical strength of heat-treated parts.

Enhanced the Photocatalytic activity of Ammonia doped CuS Grown by Hydrothermal Route

Y C Goswami

CuS nanoparticles (NPs) with dimensions in the nanometer range were synthesized using a wet chemical approach. The comprehensive characterization of these NPs involved an analysis of their structure, composition, and optical properties, primarily conducted through X-ray diffraction (XRD) analysis. The XRD pattern conclusively confirmed the presence of the hexagonal phase in the CuS particles, a result corroborated by the accompanying Raman spectrum. The investigation further determined an estimated bandgap energy of 2.05 eV for the slightly sulfur-rich CuS NPs. Notably, this energy value exceeds that of bulk CuS (1.85 eV), indicating a noticeable miniaturization effect. The novel CuS NPs exhibited outstanding photocatalytic activity in the degradation of methyl Red (MR), particularly under visible light. This impressive performance is attributed to surface-bound OH ions on the CuS nanostructures, facilitating the adsorption and acceleration of the degradation process for MR molecules under visible light irradiation. The research presented in this article highlights the significant promise and efficiency of the synthesized CuS NPs as photocatalysts. These nanoparticles are particularly responsive to stable visible light, making them highly suitable for purifying chemically contaminated wastewater. Specifically, their effectiveness in degrading stable azo dyes, exemplified by MR, underscores their potential in practical applications.

Mechanical Properties of Glass-Ionomer Cement Composited by ZrO2 and CaMgSi2O6 in Submicron Particle Size: Their Acidic-Basic Behaviors in The Presence of Poly Acrylic Acid

Hamidreza Rezaie

Glass ionomer cements (GICs) are widely utilized in clinical restorative dental applications, which suffer from poor mechanical strength. Recent research shows that GIC achieves optimal performance when modified with lower percentage of filler materials, particularly when using nanoparticles, due to the resultant increase in surface area and packing density of the cement. Notably, while some modifications show promise, others fail to deliver improvements in material characteristics. This study addressed a gap in the literature by investigating the impact of acidic/basic additives, such as Diopside (CaMgSi₂O₆) and Zirconia (ZrO₂), on the properties of the cement. The reactivity of zirconia and Diopside differ distinctly from traditional calcium-aluminosilicate glass when exposed to acidic conditions in GICs. Also, to clarify the impact of acidity/basicity on filler reactivity during cement setting, the potential mechanical enhancement effects by using nano-sized particles is limited to submicrons. This research incorporated Diopside at concentrations of 2, 4, and 6 wt.%, and zirconia at 8, 10, and 12 wt.% into a glass powder component. Results demonstrated that adding 8 wt.% Zirconia led to a 49% enhancement in compressive strength, also improve microhardness by 16 wt.%, attributed to its non-reactive nature, minimal dissolution, and high inherent strength of ZrO₂. In contrast, Diopside had a detrimental effect due to its basic nature compared to that of glass powder. These findings highlight the potential of zirconia as a valuable reinforcing material for the successful mechanical performance of glass ionomer cements. Conversely, basic fillers like diopside appear unsuitable for achieving improved mechanical performance in these systems.

“Impact of Grain Reduction on the Behavior of AZ91 Magnesium Alloys During Wear and Corrosion”

Ramesh S

Magnesium and the alloys made from the same metal are utilized in the engineering applications such as automotive, marine, and aircraft, among others due to high strength to weight. Nevertheless, the applications of magnesium alloys are currently limited to a certain level due to their poor wear and corrosion properties. Another effective strategy for enhancing these properties involves utilizing the process of equal channel angular extrusion (ECAE), which serves to refine the grain structure, thereby resulting in improved material properties. This paper aims to establish the relationship between grain size reduction and wear and corrosion of AZ91 alloy. The wear performances of both coarse-grained and fine-grain alloy were conducted using L9 orthogonal array of experiments in order to study the effects of control parameters on wear performance. In the study, it has also been identified that through ECAP, the corrosion barrier and wear characteristics of the alloy were enhanced due to fine-grain-structure and the spheroidal precipitation of the second β-phase particles. Further, the influence of these changes on the performance of the AZ91 Mg alloy was assessed using SEM.

Various Architectures of Colloidal Cu3(MoO4)2(OH)2 and Cu3Mo2O9; Thermal Stability, Photoluminescence and Magnetic Properties of Cu3(MoO4)2(OH)2 and Cu3Mo2O9 Nanosheets

Azam Bayat

The lindgrenite compounds [Cu₃(MoO₄)₂(OH)₂] with various architectures and high crystallinity were prepared by a simple surfactant-assisted hydrothermal method. Then, the Cu₃Mo₂O₉ samples were prepared by calcination of the as-synthesized Cu₃(MoO₄)₂(OH)₂. The resulting samples had high crystallinity, colloidal properties, high-yield, large-scale production capability with using of nontoxic and inexpensive reagents and water as an environmentally solvent. The scanning electron microscope studies showed that the as-prepared lindgrenite nanostructures were well crystallized with rod, sheet and hollow sphere morphologies. These products were content of the Cu₃(MoO₄)₂(OH)₂rods with diameters of about 100 nm, the Cu₃(MoO₄)₂(OH)₂nanosheets with thickness of 30–100 nm and the Cu₃(MoO₄)₂(OH)₂hallow spheres, consisting of a large number of nanosheets with thickness of about 40-70 nm. The Cu₃Mo₂O₉ samples that obtained by thermal treatment of lindgrenite retained the original morphologies. Meanwhile, the photoluminescence and magnetic properties of the nanosheet samples showed super paramagnetic behavior at room temperature and in comparison with previous works, Cu₃(MoO₄)₂(OH)₂ and Cu₃Mo₂O₉ samples synthesized by the surfactant-assisted hydrothermal method had a very obvious red-shifted PL emission and high intensity.

Electro-Optical Properties of Cesium Lead Iodide: A Computational Approach.

Mohammad Abdullah Al Asad

Perovskite materials have accumulated considerable attention in recent years for their exceptional electro-optical properties, creating them rising candidates for various uses in the fields of photovoltaics, light-emitting devices, and beyond. Among these perovskite materials, CsPbI₃ stands out as a notable example due to its remarkable stability, tunable bandgap, and efficient light-emitting properties. The crystal structure, composition, and introductory properties of CsPbI₃ perovskite using density functional theorem (DFT) being focused. In detailed exploration of Electronic property, Elastic property, Optical property, Population analysis, and shedding light on the unique attributes of this material highlighted this study. To do above computation we have used CASTEP in Material Studio.

Influence of Composition and Process Parameters on Aluminide Coatings Thickness: An Explainable Machine Learning-Assisted Approach

Saeed Rastegari

Aluminide coatings are widely used in high-temperature applications due to their excellent corrosion resistance and thermal stability. However, optimizing their composition and thickness is crucial for enhancing performance under varying operational conditions. This study investigates the optimization of aluminide coatings through a data-driven approach, aiming to predict the coating thickness based on various composition and process parameters. A comparative analysis of six machine learning models was conducted, with the k-nearest neighbors regressor (KNNR) demonstrating the highest predictive accuracy, yielding a coefficient of determination R² of 0.78, a root mean square error (RMSE) of 18.02 µm, and mean absolute error (MAE) of 14.42. The study incorporates SHAP (Shapley Additive Explanations) analysis to identify the most influential factors in coating thickness prediction. The results indicate that aluminum content (Al), ammonium chloride content (NH₄Cl), and silicon content (Si) significantly impact the coating thickness, with higher Al and Si concentrations leading to thicker coatings. Zirconia (ZrO₂) content was found to decrease thickness due to competitive reactions that hinder Al deposition. Furthermore, the level of activity in the aluminizing process plays a crucial role, with high-activity processes yielding thicker coatings due to faster Al diffusion. The pack cementation method, in particular, produced the thickest coatings, followed by gas-phase and out-of-pack methods. These findings emphasize the importance of optimizing composition and processing conditions to achieve durable, high-performance aluminide coatings for high-temperature applications.

The Effect of TiO2 Addition on the Microstructure, Crystallization and Dielectric Behavior of BaO- Al2O3- SiO2 Glass System

seyed mohammad Mirkazemi

This study systematically investigates the crystallization behavior, phase evolution, and dielectric properties of a BaO-Al₂O₃-SiO₂ glass system modified with 10 wt% TiO₂. Thermal characterization revealed that TiO₂ addition notably reduced the glass transition temperature (from 781.6°C to 779.4°C) and softening point (from 838°C to 824.8°C) compared to the TiO₂-free glass, consequently decreasing the calculated nucleation temperature (from 810°C to 800°C). While differential thermal analysis indicated sluggish crystallization kinetics, isothermal heat treatments identified 1000°C as the optimal processing temperature, leading to the development of a multiphase crystalline assemblage that beneficially included the target monoclinic Ba_3.75Al_7.5Si_8.5O₃₂ phase, which was absent in the TiO₂-free glass. X-ray diffraction identified this phase, along with celsian (BaAl₂Si₂O₈) polymorphs and barium titanate crystallites, as the dominant crystalline phases. SEM revealed anisotropic crystal growth (1.14-1.52 μm length). Dielectric characterization in the Ku-band (12.4-18 GHz) demonstrated significant property enhancements, with the relative permittivity decreasing from 10.40 to 6.38 and loss tangent improving from 0.3 to 0.2 after crystallization. These improvements, attributed to the specifically tailored crystalline phase assemblage facilitated by TiO₂, make this glass-ceramic system particularly suitable for advanced microwave applications requiring low dielectric loss and high-frequency stability. The effectiveness of TiO₂ as a crystallization modifier for achieving optimized dielectric properties through controlled devitrification and targeted phase formation is underscored.

Synergistic Enhancement of Hydrophilicity in Silk Fibroin/Linen Blends via Polyethylene Glycol and Curcumin for Advanced Wound Healing

Fatemeh Rafati

It must be recognized that the degree of this factor will influence how well wound-healing materials perform water absorption, protein interaction, and cellular adhesion. In the present study, we are concerned with studying the effects of polyethylene glycol (PEG) and curcumin (Cur) on the hydrophilicity of silk fibroin (SF)/linen (LN) composite films. The SF and LN composite films were blended at an equal mass ratio of 1:1, and PEG and Cur were also added to induce changes in surface properties. Fourier-transform infrared analyses showed that intermolecular interactions and hydrogen bonding were formed among the components in the blends. There was a very obvious hydrophobicity reduction by the addition of Cur and PEG/Cur, as exemplified by the static water contact angle measurements: simply addition of Cur to SF lowered the contact angle from approximately 100° to 72°, whereas a co-addition of PEG and Cur produced the greatest reduction (64°), equalling 70%. The synergistic effect in the surface wettability enhancement occurs because both additives introduce polar moieties onto the surface and partially disrupt the SF crystalline structure. Water uptake and cell viability tests further verified the hydrophilicity and biocompatibility of PEG/Cur-modified SF/LN films. This promotes the use of PEG/Cur-modified SF/LN blends as hydrophilic, bioactive materials suited for advanced wound dressing and tissue engineering scaffolds.

Plasma Time and Power Sequence Impact on Wettability Tuning and Mechanical Properties of Fluorinated Monolayer Graphene

Asiehsadat Kazemi

Fluorinated graphene is an up-rising member of the graphene family and attracts significant attention since it is a 2D layer-structure, is self-lubricating, has wide bandgap and high thermal and chemical stability. By adjusting the C–F bonding character and F/C ratios through controlled fluorination processes, fluorinated graphene can be utilized for a wide range of applications including energy conversion, storage devices, bio- and electrochemical sensors. Herein, monolayer CVD graphene/Cu was fluorinated via SF₆ plasma with time and power sequence trial. Structural, morphological, roughness, adhesive forces, and wettability of fluorinated graphene was explored. Insight was gained by Raman spectroscopy, SEM and EDS, surface roughness and adhesive force measurements via AFM on different samples. Fluorination produced p-doped structure, blue shift in the 2D peak and red shift in D peak of the Raman spectra of graphene. Increase in plasma time increased the defects and weakened C-C bonds much more rapidly at higher plasma power (40W) while lower plasma power (15W) retained more of graphene properties (having high L_a, L_D and low n_D) confirmed by Raman, SEM and EDS analyses. Surface roughness and adhesive forces on graphene surface were mostly increased with the increase in plasma time at a certain power. Higher plasma power resulted in more hydrophobic surfaces and even the wettability tuning occurred in the hydrophobic regime while lower plasma power demonstrated tuning in the hydrophilic regime. Influence of the underlying surface and π -electron pairs were shown to play more significant roles in tuning the wettability at higher plasma power.

Synthesis and Characterization of the PP Fibers Coated by ZnO Nanoparticles: Investigation of Antibacterial Properties

Salahaldin Mansur Alduwaib

This research is focused on the synthesis of zinc oxide nanoparticles by means of the sol-gel conventional method, followed by the formulation of a zinc oxide-polypropylene (ZnO: PP) masterbatch using a twin-screw extruder. The next step involved the fabrication of antibacterial fibers through electrospinning. The resulting Nano powders, masterbatch, and fibers were subjected to a series of characterization techniques. X-ray diffraction (XRD) was used to examine the crystalline structure, field emission scanning electron microscopy (FESEM) was employed to scrutinize the morphology of the samples, energy-dispersive X-ray spectroscopy (EDX) was adopted for elemental analysis, and Fourier-transform infrared spectroscopy (FTIR) was hired to identify the chemical bonds.
Thermogravimetric analysis (TGA) indicated a three-stage weight loss process, and differential scanning calorimetry (DSC) showed a primary endothermic peak centered at about 317 °C and a pronounced exothermic peak at approximately 455 °C. XRD confirmed the hexagonal wurtzite structure of the zinc oxide nanoparticles and the presence of the alpha (α) crystal form in polypropylene. FESEM imaging revealed that the zinc oxide and masterbatch samples had a uniform size and shape, predominantly in the nanometer range with an elongated spherical morphology. The antibacterial properties of polypropylene fibers containing varying concentrations of zinc oxide, including 1.2, 2.4, and 5 wt.%, were tested against Escherichia coli and Staphylococcus aureus.