Materials Science Forum

Preface

Fri, 14 Aug 2026 00:00:00 +0200

Publication date: 14 August 2026
Source: Materials Science Forum Vol. 1199

Machine Learning Prediction of Optical Absorption in GaAs 2D Nanostructure under Hydrostatic Pressure

Fri, 14 Aug 2026 00:00:00 +0200

Publication date: 14 August 2026
Source: Materials Science Forum Vol. 1199
Author(s): I. Lamrini, M. Hbibi, S. Chouef, M. El Hadi, R. Boussetta, O. Mommadi, A. El Moussaouy, K. Laabidi, C.A. Duque
This work focuses on the modeling and prediction of the optical absorption coefficient in GaAs 2D nanostructure subjected to hydrostatic pressure. The database is generated from numerical calculations describing the optical absorption of exciton confined in GaAs 2D nanostructure. The obtained data are exploited to develop predictive models based on machine learning such as Decision Tree and Gradient Boosting techniques, in order to establish an accurate relationship between the incident photon energies and the optical absorption coefficient. The quality of the proposed approaches is examined using standard statistical metrics, considering the mean absolute, squared errors, and root mean squared error, as well as the coefficient of determination. The obtained results demonstrate an excellent agreement between the predicted and numerical values, with very low errors and strong generalization capability. these approaches therefore represent an efficient alternative to conventional numerical methods for the rapid prediction of the optical properties of discoidal quantum dots and offers promising perspectives for the optimization of optoelectronic devices.

Influence of Nonlinear Crystal Properties on Entanglement Generation in Spontaneous Parametric Down-Conversion (SPDC) Sources

Fri, 14 Aug 2026 00:00:00 +0200

Publication date: 14 August 2026
Source: Materials Science Forum Vol. 1199
Author(s): Hiba Chakir, Farid Abdi, Fouad Mohammed Abbou
The generation of entangled photon pairs through spontaneous parametric down conversion (SPDC) is widely used and considered one of the key entanglement generation techniques in quantum optics. The quality of the entanglement produced depends significantly on the physical properties of the nonlinear crystal employed in the SPDC process. In this study, we investigate the influence of the crystal parameters such as phase matching configurations on the degree of entanglement. Our results demonstrate the importance of crystal selection for achieving highly entangled photon sources, which are essential for applications in quantum communication and quantum information.

Investigation by First-Principles Calculation of the Structural and Electronic Properties of Hexagonal SrLiP

Fri, 14 Aug 2026 00:00:00 +0200

Publication date: 14 August 2026
Source: Materials Science Forum Vol. 1199
Author(s): Bejja Nihad, Bencheikh Mounaim, Darhi Zakariae, Farid Falyouni, Larbi El Farh
In this work, the structural and electronic properties of the ternary phosphide SrLiP, which crystallizes in the hexagonal space group P6 ̅2m (N°.187), were investigated using Density Functional Theory (DFT). To optimize the equilibrium geometry, we used the Generalized Gradient Approximation (GGA) with the Full-Potential Linearized Augmented Plane-Wave approach (FP-LAPW) method. The optimized structure is found to be mechanically stable. The calculated electronic band structure of SrLiP, within GGA approach shows that it exhibits a semiconducting behavior with an estimated band gap of about 0.85 eV. The projected density of states (PDOS) indicates that the top of the valence band is mainly dominated by P-p states, while Sr and Li orbitals contribute significantly to the bottom of the conduction band, indicating hybridization effects governing the electronic transitions. Owing to its structural stability and moderate band gap, SrLiP may represent a promising candidate for potential optoelectronic applications.

Recent Stable Semiconducting SiC Nanocluster for Protecting Soft Metals in Energy Conservative Systems: A Quantum Chemistry Analysis

Fri, 14 Aug 2026 00:00:00 +0200

Publication date: 14 August 2026
Source: Materials Science Forum Vol. 1199
Author(s): Fatemeh Mollaamin, Majid Monajjemi
Semiconducting silicon carbide (SiC) has been developed and characterized as an anode electrode for lithium (Li), sodium (Na), potassium (K), beryllium (Be), magnesium (Mg), boron (B), aluminum (Al), and gallium (Ga) ion batteries. This is due to the formation of Si(Li2)C, Si(Na2)C, Si(K2)C, Si(Be2)C, Si(Mg2)C, Si(B2)C, Si(Al2)C, and Si(Ga2)C nanoclusters. A comprehensive study on energy savings using Si(Li2)C, Si(Na2)C, Si(K2)C, Si(Be2)C, Si(Mg2)C, Si(B2)C, Si(Al2)C, and Si(Ga2)C complexes was conducted using computational approaches, including density of state analysis, charge density differences (CDD), total density of state (TDOS), and electron localization function analysis (ELF) for hybrid clusters of Si(Li2)C, Si(Na2)C, Si(K2)C, Si(Be2)C, Si(Mg2)C, Si(B2)C, Si(Al2)C, and Si(Ga2)C. Functionalizing lithium, sodium, beryllium, and magnesium elements can enhance the negative charge distribution of carbon elements as electron acceptors in Si(Li2)C, Si(Na2)C, Si(K2)C, Si(Be2)C, Si(Mg2)C, Si(B2)C, Si(Al2)C, and Si(Ga2)C nanoclusters. Increased Si/C content can boost battery capacity through Si(Li2)C, Si(Na2)C, Si(K2)C, Si(Be2)C, Si(Mg2)C, Si(B2)C, Si(Al2)C, and Si(Ga2)C nanoclusters for energy storage processes and improve rate performance by enhancing electrical conductivity. Additionally, the SiC anode material may improve cycling consistency by reducing electrode degradation and increasing capacity due to higher surface capacitive effects.

Formation Enthalpy and Phase Behavior of Fe–Al–Ni Alloys: A Thermodynamic and Theoretical Spectroscopic Study

Fri, 14 Aug 2026 00:00:00 +0200

Publication date: 14 August 2026
Source: Materials Science Forum Vol. 1199
Author(s): Fatima Hussian Jabar, Ali Kadhim Alsaedi
Thermodynamic behavior and phase stability of binary and ternary alloy systems containing Fe, Al, and Ni are systematically investigated. Formation enthalpies (ΔH) of solid solutions and intermetallic compounds in the Fe–Al, Fe–Ni, Al–Ni, and Fe–Al–Ni systems were calculated using Miedema’s semi-empirical model implemented in the Materials Analysis Applying Thermodynamics (MAAT) software. Overall, the results indicate that solid solutions in the binary systems are thermally stable, and when the concentration of alloying elements is increased, solids solutions demonstrate a low change in thermal behavior while compounds exhibit more complex thermodynamic behavior and require higher energy for formation. The ternary Fe–Al–Ni system also exhibits exothermic and endothermic reactions according to the molar ratio of elements. The electronic and vibrational properties of the Fe₈₀Al₁₅Ni₅ alloys are theoretically simulated using DFT and TD-DFT for UV–Visible calculations, and the spectroscopic features are interpreted in correlation with the thermodynamic stability predicted by Miedema’s semi-empirical model. No experimental spectroscopic measurements were performed in this study.

Failure Mechanisms and Shunt Effect Phenomenon in Single- and Double-Nugget Resistance Spot Welded HSLA Steel

Fri, 14 Aug 2026 00:00:00 +0200

Publication date: 14 August 2026
Source: Materials Science Forum Vol. 1199
Author(s): Hayder H. Khaleel, Ibtihal Mahmood, Fuad Khoshnaw
This work presents an experimental investigation for the failure mechanisms and shunt effect phenomenon in resistance spot welded high-strength low-alloy (HSLA) steel sheets with single-and double-nugget configurations. Welded joints were produced under controlled conditions following to ISO/DIS 14273:2016 standard, and their performance was assessed through tensile-shear testing, microhardness measurements, and microstructural analysis. The results revealed a clear influence of nugget configuration on both mechanical strength and fracture behavior. Single-nugget welds primarily exhibited interfacial and partial pull-out failures, whereas double-nugget welds demonstrated combined pull-out and sheet-tearing modes, indicating improved energy absorption and joint integrity. Microstructural observations showed refined martensitic zones in the fusion region, with hardness values significantly higher than those of the base metal. The shunt effect phenomenon observed in double-nugget welds led to noticeable variations in nugget diameter and hardness symmetry, influencing current distribution and local heat input.

Observation of the Effect of Periodic Vibration on the Phase Transition of VO2 Thin Film

Fri, 14 Aug 2026 00:00:00 +0200

Publication date: 14 August 2026
Source: Materials Science Forum Vol. 1199
Author(s): Samee Azad, Durga Gajula, Makhluk Hossain Prio, Goutam Koley
The impact of periodic mechanical vibration on the phase transitional property of VO2 based thermal sensing thin film synthesized on AT-cut quartz has been investigated in this paper. VO2 were found to go through phase transition due to effect of heat, and display reduction of film resistivity and transmitted infrared power at a specific transition temperature, typically around 60-70°C. But sometimes the transmitted infrared power has been observed to decrease at a significantly lower temperature compared to the similar phenomenon for resistivity reduction. In order to correctly validate the transition temperature, the derivative of the transmitted optical power signal is measured, and it has been found that this measurement is experimentally possible when the VO2 film is subjected to a moderate to high frequency periodic mechanical vibration. It has also been observed that the variation of the mechanical vibration frequency has a direct effect on the derivative signal, which indicates the sharpness of the phase transition and magnitude of change of the transmitted infrared power depending on the width of the extrema lobe of the derivative.

Dual Solutions and Temporal Stability of MHD Al₂O₃–Cu/Water Hybrid Nanofluid Flow over a Bidirectional Shrinking Sheet in a Porous Medium

Fri, 14 Aug 2026 00:00:00 +0200

Publication date: 14 August 2026
Source: Materials Science Forum Vol. 1199
Author(s): Abdul Rahman Mohd Kasim, Siti Maryam Hafiza Mohd Kanafiah, Adeshina Taofeeq Adeosun, Noor Amalina Nisa Ariffin, Nurul Amira Zainal
This study investigates the dual solution existence and the associated temporal stability of magnetohydrodynamic hybrid nanofluid (HNF) flow over a bidirectional shrinking sheet. The working fluid consists of an Al₂O₃–Cu/water HNF subjected to suction, magnetic field effects, and porous medium resistance. The reduced coupled ordinary differential governing equations are solved using the Galerkin weighted residual method. A temporal stability analysis based on eigenvalue formulation is conducted to distinguish physically realizable solutions from unstable ones. The effects of emerging parameters on the skin friction coefficients and the Nusselt number are examined with the concentration given on magnetic effect. The results reveal the dual solution existence in a critical range of suction values, beyond which no solutions exist, indicating boundary-layer separation. Stability analysis confirms that only the upper-branch solution is stable and physically admissible. Enhanced magnetic field strength, delay boundary-layer separation and improve thermal performance. The present results show excellent agreement with previously reported limiting cases, demonstrating the accuracy and robustness of the proposed method.

Revisiting the Viscoelastic Theory of Superionic Conductor Ag2+δSe and its Implication to Thermoelectric Materials

Fri, 14 Aug 2026 00:00:00 +0200

Publication date: 14 August 2026
Source: Materials Science Forum Vol. 1199
Author(s): Masaru Aniya
In recent years, thermoelectric materials based on noble metal chalcogenides are attracting considerable interest due to their high figure of merit. On the other hand, it is well known that noble metal chalcogenides exhibit high ionic conductivity. By looking the reported experimental data, there are wide evidences that the thermoelectric and high ionic conduction behavior are interrelated. In the present study, the viscoelastic theory of superionic conductors which was used previously to study the properties of Ag2+δSe is reconsidered. The model predicts that the composition dependence of the sound velocity and diffusion coefficient near the stoichiometric composition exhibit a minimum and maximum respectively, when the value of the Thomas-Fermi screening parameter is decreased. Such a behavior provides an insight to exploit the alloying effect in the development of thermoelectric materials. In addition to the results from the viscoelastic theory, the electronic transport properties provided by the bond fluctuation model of superionic conductors is also discussed shortly.

Characterization of Polymer Composites Reinforced with Metal Particles

Fri, 14 Aug 2026 00:00:00 +0200

Publication date: 14 August 2026
Source: Materials Science Forum Vol. 1199
Author(s): Marianna Mátyus, Dóra Mentes, Béla Fiser, Tamás József Szabó
This study is part of my doctoral research and investigates the sustainable recycling of aluminum waste through the development of aluminum-containing polymer hybrid materials. The study aims to understand how the type, structure, and distribution of these reinforcements influence the mechanical strength and overall behavior of the composites. The increasing demand for lightweight, high-performance, and environmentally friendly materials in various industries - such as automotive, construction, and packaging - has driven the exploration of metal-polymer composites. In this context, aluminum, due to its low density, corrosion resistance, and recyclability, presents a promising candidate for reinforcement in polymer matrices. Special attention was given to how the particle size and distribution affect the elasticity, flexibility, and structural integrity of a selected PU-foam. The study aims to contribute to the broader field of circular materials engineering by offering insights into how industrial aluminum waste can be effectively reused in high-value polymer systems.

Crystallinity Transformation in Pulverized Polyphthalamide for Sustainable Polymer Engineering

Fri, 14 Aug 2026 00:00:00 +0200

Publication date: 14 August 2026
Source: Materials Science Forum Vol. 1199
Author(s): Yevhen Yekymov, Vladimir Lebedev
Mechanical recycling of high-temperature semi-aromatic polyamides remains challenging due to their high melting temperatures and limited processability. In this study, secondary glass-fiber-reinforced polyphthalamide was processed by two mechanical size-reduction routes: conventional crushing and pulverization in an industrial high-speed dual-disc pulverizer. Structural and thermal changes were evaluated by Fourier Transform infrared spectroscopy, X-ray diffraction and differential scanning calorimetry. Fourier Transform infrared spectroscopy confirms that both routes preserve the polyphthalamide backbone, while the pulverized material shows subtle changes in the N-H and C=O regions consistent with partial reorganization of the hydrogen-bonding network. X-ray diffraction shows a decrease in apparent crystallinity from ~24.2% (crushed) to ~18.4% (pulverized), accompanied by an increase in average crystallite size from ~10.3 to ~12.8 nm, suggesting lamellar-scale restructuring. Differential scanning calorimetry analysis emphasizes the first heating as a probe of the as-processed condition: the pulverized secondary glass-fiber-reinforced polyphthalamide exhibits a lower melting enthalpy (≈17 J/g versus ≈23 J/g for the crushed reference) and a distinct cold-crystallization peak near 166 °C. This feature is not observed in the crushed material and disappears after melting and controlled cooling, whereas Tg and Tm remain largely unchanged. Overall, X-ray diffraction and differential scanning calorimetry consistently show that the pulverized powder differs from the crushed reference mainly in first-heating enthalpy and the appearance of cold crystallization, while Tg and Tm remain similar. From an application perspective, pulverized secondary glass-fiber-reinforced polyphthalamide is a fine, heat-stable recycled feedstock that can be reintroduced more readily into polyamide blends and compounds, providing a simple, solvent-free route to enhance the engineering value of recycled high-temperature polyphthalamide.

Application of Timoshenko Beam Theory in Finite Element Simulation of Fiber-Reinforced Composite Material

Fri, 14 Aug 2026 00:00:00 +0200

Publication date: 14 August 2026
Source: Materials Science Forum Vol. 1199
Author(s): László József Mónus, Enikő Réka Fábián
The limbs of compound bows are subjected to highly complex and intensive mechanical loads throughout the entire shooting cycle. Due to the operation of the cam system, forces acting on the limbs may exceed the applied draw force by several times, particularly near maximum draw. Extreme dynamic loads can be generated during dry firing, which may result in sudden and often fiber-directional failure of composite limbs. Local stress levels are further increased by stress concentration effects arising from geometric and material inhomogeneities. In this study, the forces acting on the cam system and the bow limbs were determined through preliminary analytical calculations. The Euler–Bernoulli beam theory was applied to estimate limb deflection analytically. The analysis was refined using the Timoshenko beam model to account for shear deformation and cross-sectional rotation. Cross-sectional second moments of area and relevant material properties were determined to ensure accurate results. The calculated deflections, although small in magnitude, were shown to have a significant influence on the stress state of the limbs. Based on the numerical results, it was concluded that compound bow limbs operate close to, or in some cases beyond, their material limit under severe loading conditions.

A Comparative Study on the In Vitro Degradation of PLA Processed by FFF and Film Extrusion

Fri, 14 Aug 2026 00:00:00 +0200

Publication date: 14 August 2026
Source: Materials Science Forum Vol. 1199
Author(s): Kardo Khalid Abdullah, Kolos Molnár
Processing methods strongly influence the degradation behaviour of semi-crystalline polylactic acid (PLA) by affecting its molecular orientation, crystallinity, and micro-and macrostructural features. In our previous study, we presented the changes in the properties of the electrospun PLA fibers during in vitro degradation. Building on these findings, this study compares the degradation of PLA specimens prepared using two bulk processing methods: (i) fused filament fabrication (FFF) 3D printing and (ii) film extrusion. Specimens were incubated in phosphate-buffered saline (pH 7.4) at 37 °C for 1, 3, 7, 28, and 56 days. At each time point, degradation was assessed by tensile testing, differential scanning calorimetry, and weight retention analysis. PLA films exhibited an initial decrease in Young’s modulus, followed by a temporary increase and subsequent decline, whereas FFF specimens maintained mechanical stability for several days before a gradual deterioration. Both specimens showed reduced crystallinity over time, with FFF samples becoming fully amorphous by day 56. Minimal weight change (<1%) indicated that degradation proceeded primarily through structural and morphological changes rather than bulk erosion. Overall, 3D-printed PLA exhibited more stable mechanical properties than extruded PLA films. These findings highlight the significant impact of the processing route on PLA degradation, guiding the optimization of PLA performance in biomedical, packaging, and sustainable material applications.