Iqbal Alshalal

Friction-type bolted joints are widely used in both the civil and aerospace industries. Uncontrolled excessive bolt clamping force can cause damage to the laminated fiber-reinforced polymeric (FRP) composite through the thickness and damage the joint before applying the service loads. The effect of the friction coefficient (between 0 and 0.3), bolt clearance, joint type, and other parameters on failure modes and the maximum bolt clamping force of the carbon FRP lapped joint is studied. A three-dimensional finite element (FE) model consisting of a bolt, a washer, a laminate FRP composite plate, and steel plates was developed for the simulation of the double- (3DD) and single (3DS)-lapped bolted joint. The FE model was validated by using experimental results and was able to predict the experimental results by a difference of between 2.2 and 6.7%. The joint capacity of the clamping force was found to be greatly increased by adopting the double lap technique, which involves placing an FRP composite plate between two steel plates. Also, it was recommended to use an internal washer diameter less than or equal to the FRP composite plate hole diameter since a larger washer clearance can produce higher contact pressure and reduce the resistance by 22%. In addition, reducing the bolt head diameter can lead to a 65% reduction in the 3DS joint clamping strength.

Using torch brazing techniques, 316 stainless steel was brazed to CP copper using flux-coated low silver content filler with 20% Ag. The brazing torch utilized a fuel mixture of propane gas with oxygen to produce the required heating amount due to the possibility of economic interest in employing...

Accurate representation of a photovoltaic solar cell requires a comprehensive assessment of modeling factors that are unique to the individual device being studied. In the context of the single diode model, it is necessary to ascertain five distinct parameters, namely Rs, Rsh, Iph, Io, and n. In general, analytical or numerical methods may be used to calculate these values. In this paper, two alternative iterative approaches to solving nonlinear problems in solar cells without temperature are described and analyzed. The new iterative approach has several instances that have been quantitatively tested. This novel approach can be seen as a potential option for solving nonlinear equations. Additionally, a comparison between the suggested method, classic chord formula (CCM), and predictor-corrector type reveals that it is better and has the lowest evaluation. This is supported by an examination of accuracy and efficiency (as evaluated by function evaluations) false position method (FPM).

The correlation between structural and optical properties of an Au, ITO, and ITO/Au/ITO (IUI), gold, indium tin oxide, and indium tin oxide/gold/indium tin oxide, respectively, sandwich structure thin film has been reported in this study. The deposition of all samples onto glass substrates was carried out using D.C. magnetron sputtering, without the use of substrate heating, and the intermediate layer was a metallic gold film with an 8 nm thickness. The substrate-target distance in the IUI structure was kept constant at 8 nm. X-ray diffraction (XRD), atomic force microscopy (AFM), and scanning electron microscopy (SEM) are often utilized techniques for the evaluation of the structural and surface morphology of films. The optical properties of the films were demonstrated by a spectrophotometer (UV/vis/NIR) and spectroscopic ellipsometry (SE) techniques adopted for the new amorphous model, and the findings were compared with those between 200 and 2200 nm, where the wavelengths overlap at room temperature, which is the purpose of the present work. The observed and estimated optical constant values of the Au, ITO, and IUI films using the best dispersion model were reported. In addition, the transmission and reflection spectrum results of the films were compared with those obtained by UV measurements. Excellent correlations for the optical constant properties of the multilayer films were observed employing two distinct approaches. These thin films have great promises for the future of transparent conductive oxides (TCOs) and even industrial applications

With the development of laser technology in various fields of engineering and manufacturing in terms of many uses in these areas and in the field of improving the mechanical properties of different metals for their ability to withstand different thermal and mechanical stresses and stresses. Wherein this research paper the addition of nanomaterials and laser heat shedding on them and knowing their ability to improve. The design process of the simple model that complies with the requirements of the simulation process was in the solid works program. The investigated dimensions were (100×100×10) mm³ in height, split up in the form of two portions. The partition itself is the path of the laser used. It is necessary to check the reliability of the mesh to form an appropriate mesh that can give accurate results. The nanoparticles where Al₂O₃ and TIC were used in different proportions with the base material. Which is steel, where these ratios were (0.3, 0.6, 1) wt %, where the results proved the process of adding nanomaterials has positive effects in terms of the materials' tolerance to heat, mechanical stress, and the surrounding conditions. Seen through the results with the increase in the concentration values of adding nanoparticles, get a significant effect on the results and the values of thermal and mechanical properties. The TIG (Tungsten inert gas) nanomaterial led to an increase in temperatures in the solid by 1 wt % compared to the rest of the concentrations and nanomaterials. The addition of nanomaterials in heat treatments has a positive effect on the amount of deformation, as the lowest value of deformation was obtained in nanomaterials at tic1 wt % compared to the rest of the concentrations. As for the stresses, the largest stress obtained is 10.502 Gpa

This research is an experimental comparison study to show the influence of mold type casting on mechanical properties. The study considers the aluminum alloy of a gasoline engine piston with nanoparticles alumina Al2O3 size 25 nm manufactured in two types of molds. Sand mold and cast-iron mold were selected to cast the aluminum composite components. A systematic comparative study of tensile strength and hardness properties of cast aluminum components is made on sand and metal molds production. The nano powder can add to enhance the mechanical properties must not exceed 4 % for metal and sand mold casting. According to data for hardness, adding nano alumina powder has minimal impact on metal mold casting, but it significantly improves sand casting. From a financial standpoint, metal casting provides higher economic values for making piston aluminum castings. The hardness rises as the alumina content does in two molds as compared to the obtained specimen. It demonstrates that the highest hardness occurs at 4 % alumina in the sand-casting mold and at 6 % alumina in the metal. When the compositions of the casting materials are the same, a comparison of the fracture morphology between sand and mold casting reveals more ductile fractures for metal molds compared to brittle fractures in sand cast by large silicon separation grains because of higher grain growth in sand casting by longer solidification time. The same is seen in mold casting, which exhibits reduced ductility due to the alumina nanoparticles' dispersion strengthening process in the aluminum matrix. This arises as a result of nano alumina dispersion acting as barriers to dislocation motions in the aluminum matrix, enhancing strength but reducing ductility.

A practical study was conducted to improve the performance of conventional pyramidal solar stills (CPSS) using two types of fins with differing geometries, as well as nanocomposites of TiO₂ and graphene. The first fin was hollow, cylindrical, and perforated (HCPF), whereas the second fin was an inclined perforated rectangular fin (IPRF). The fins were integrated with the base of a solar still to evaluate their performance in comparison with a CPSS. The obtained experimental results demonstrated that the pyramidal solar still with hollow perforated cylindrical fins (PSS-HCPF) and the pyramidal solar still with inclined perforated rectangular fins (PSS-IPRF) produced more distillate than the PSS-HCPF and CPSS under all examined conditions. The daily productivities of the CPSS, PSS-HCPF, and PSS-IPRF were 3718, 4840, and 5750 mL/m², respectively, with the PSS-HCPF and PSS-IPRF improving the productivity by 31.3% and 55.9%, respectively, compared to that of the CPSS. In addition, using nanocomposites with PSS-IPRF improved the daily distillate production by 82.1%.

Cast iron is considered a very common material for manufacturing applications due to its low cost, easy casting and high stress compression sustains. One of the obstacles in the application of cast iron are the corrosion and erosion phenomena which limits using the cast iron in certain applications. To improve the resistance rate of cast iron to corrosion and erosion. Chromium material had been added to the gray cast iron as a function of weight with different ratios to check which ratio is perfect to increase its resistance. The effect of corrosion and erosion on cast iron was investigated experimentally with and without chromium additives on the resistance of gray cast iron with and without chromium additive. Results showed that the mechanical properties increased with the increase of the chromium ratio in the four cases in general to minimize the risk of material destruction from erosion-corrosion.