Ahmed Falih Hasan

Composite materials have long been in great demand for industrial purposes, particularly in the field of lightweight automobile and aircraft applications. The theory of numerical analysis provides a useful account of how Fibre-reinforced composites can be developed to prevent failure analyses and produce new composite materials. Therefore, to get an advantage from this theory, an effort has been made in this research. A systematic, Multi-stage algorithm based on MATLAB software was established to generate a code that can manipulate data of tensile and flexural tests for composite materials made from glass fibre epoxy composites (GF/Ep) and carbon fibre epoxy composites (CF/Ep). The current numerical framework was implemented using suggested code to handle data from stress-strain curves and predict ultimate strength, strain, and fracture toughness values, undergoing a validation process. The key findings were the GF/Ep-based composite showed better strain failure and an energy absorption value of 12.3 MJ/m³/and 7.0 MJ/m³ in tension and flexure, respectively. This is suggested to have better performance in fracture toughness. Furthermore, the outcome results also showed that on GF/Ep, it is less stiff, with a value of 21.3 GPa and a bending failure value of 400 MPa.

Fiber-reinforced composites (FRCs) are among the most widely used materials in modern engineering applications due to their high mechanical properties and light weight. The current study involved a numerical investigation conducted through experimental a validation process using ANSYS Workbench R18.0 to evaluate the mechanical behavior and failure mechanism of (Carbon/Epoxy UD Prepreg). The modelling process was initiated using ACP-PRE to crate four types of laminate structures: balanced cross ply, symmetric, and random. The current model demonstrated an acceptable range of reliability and accuracy to investigate different laminate structures, with a validation error percentage of less than 8% and 13% for both static and explicit analysis. From the study, it has been concluded that the cross-ply layer structure has the highest ultimate stress, reaching 1911.2 MPa, while the random laminate structure has almost 80% in tensile strength reduction. A 700 MPa ultimate tensile stress was obtained for the cross-ply type, although the balanced laminate exhibited a weaker load response, 30 % lower than the cross-ply. Moreover, the laminate configuration of cross-ply stands as the best option in terms of reverse factor, which indicates a value of 6.7, and the highest energy of strain reached 1.5123 with 46% higher safety margin. As a result, this configuration is suggested to be the best combination and capability for the safety structure and energy absorption. These findings highlight the critical role of ply arrangement in enhancing the mechanical integrity of composite structures and support the need for deliberate design strategies in laminate engineering. Moreover, the current paper suggests ACP Pre (Advanced Composite Pre-processor) as an effective tool for simulating composite materials with layered structures.

This research aims to evaluate various coatings on titanium alloy substrates to increase corrosion resistance and surface quality. This involves coating the substrates with layers of Hydroxyapatite (HAP), Chitosan (CS), and Magnesium oxide (MgO) using the EPD technique. The cell voltage value was set to 5 V, while the coating time was set to 5, 10, and 15 min. SEM was used to measure the thickness of the cross-sectional coating layers, and it was also used to show the morphology of the composite coating. From the results 10-minute deposition time has been established as the most optimal to produce an even, thick, uniform, and dense coating with good mechanical properties. The thickness more than doubles with increases in time with the coat almost tripling at 15 minutes and 5 minutes respectively. EDX analysis showed that the elemental compositions of calcium, oxygen, and phosphorus increased after 15 minutes, indicating a dense coating. The research findings indicate that the adhesion force transitions to a marginally positive value of 0.05 nN, suggesting a weak attachment rather than a robust bond. Additionally, Young's modulus shows a significant decline to 3.93 MPa, which signifies a reduction in the stiffness of the material. The surface stiffness decreases to 0.19 nN/nm between 10 and 15 minutes, indicating a loss of rigidity. Although longer coating times may increase thickness, they can also reduce functionality and raise defect risks. This reinforces that electrophoretic deposition (EPD) effectively improves the alloy's surface quality for biomedical applications.

This study presents the electrophoretic deposition (EPD) of hydroxyapatite (HAP), chitosan (CS), magnesium oxide (MgO) and silane coupling agent (KH‐550) coatings on 316L stainless steel substrates to improve their corrosion protective properties for the intended biomedical applications. In addition, this work differentiates itself by analyzing the effects of varying anodization times (5, 10, and 15 min) on the surface characteristics, with a particular focus on the roughness, zeta potential of the suspension, and coating thickness. The results show that the root‐mean‐square roughness (Sq) and the arithmetic mean roughness (Sa) escalated from 78.18 nm to 67.14 nm on the uncoated base metal to 421.7 nm and 364.7 nm, respectively, after 15 min of anodization. Stable suspension was indicated by the zeta potential of −39.8 mV. As anodization time increased, coating thickness reached 14.14 μm after 15 min. The atomic force microscopy (AFM) analysis was used to assess the adhesion bond strengths of HAP–CS–MgO composites coated at different times on a stainless steel surface. The composite coated for 10 min exhibited the most substantial adhesion force at −0.5271 nN, indicating the highest reliability and stability in bonding interactions. The KH‐550 concentration of 0.0793 g/mL demonstrated the lowest corrosion rate at 0.02933 mm/year, indicating superior corrosion resistance, along with the highest adhesion force of −1.0 nN and a coating thickness of 117.5 μm.

In recent decades, conductive plastic has been one of the significant interesting research subjects due to its crucial importance in electronic devices and bios In recent decades, conductive plastic has been one of the significant interesting research subjects due to its crucial importance in electronic devices and bios

Considerable literature has studied different techniques to improve the thermal performance of latent heat thermal energy systems (LHTES) that utilize phase change materials (PCMs). This study aims to contribute to this growing area of research by using honeycomb structure and exploring the effect of heat transfer fluid (HTF) configuration and honeycomb cell angle on the thermal performance of the LHTES during melting and solidification processes. In this work, five cases were designed: case (a) was regarded as reference case; cases (b) and (c) were related to HTF configuration; cases (d) and (e) were used to study the effect of honeycomb cell angle. A numerical study was conducted using ANSYS FLUENT R19.3, followed by experimental validation. In this study, a good agreement is obtained from the validation process. Computational fluid dynamics (CFD) model results show symmetrical melting and solidification behavior when using a honeycomb structure. The results of the HTF configuration show a significant effect. For case (c) with a multiple water block, significant melting and solidification enhancements are obtained with 56% and 50%, respectively. Thus, the HTF configuration can improve the thermal performance of the storage. However, considering different honeycomb cell angles show an insignificant effect on the melting and solidification rates.

Free convection of various nanofluids inside concentric and eccentric annular cavity with internal heat flux, fully filled with porous media is studied numerically and its heat transfer rate and pressure drop are examined. The impact of inner cylinder inclination angles (βecc = 45^°, 135^°, 225°, and 270^°) and nanofluids (Al₂O₃/water, CuO/water and SiO₂/water) for different heat flux (1000, 2000, 3000, and 4000 w/m²) on the heat transfer rate are evaluated. Initially, a validation process has been implemented to ensure that the predicted results obtained from this model are accurate. Results indicate that Al₂O₃ Nanofluid provides a better enhancement in the heat transfer rate when compared to SiO₂ and Cu Nanofluids. Furthermore, the heat transfer coefficient increased with the inclination angle of βecc = 225^°, and maximum heat transfer occurred at a heat flux of 4000 W/m², which was roughly 6% greater than the concentric annular cylinder. The findings also indicated that while increasing the eccentricity has a minor impact on the heat transfer rate for convection-dominated flows (high heat flux), on the other hand, it has a significant impact on the heat transfer rate for conduction-dominated flows (low heat flux).