Due to their excellent thermal conductivity, lightweight, and ease of processing, aluminum alloys are the material of choice for piston manufacture in internal combustion engines. Nanoparticles (NPs) of alumina (Al2O3) with a size of 25 nm were incorporated into an aluminum piston alloy to examine the effect of the NP addition on wear resistance and fatigue behavior. The stir casting method has been utilized to manufacture experimental samples of the composite material by altering the particle weight ratio of aluminum to the matrix alloy to 2, 4, and 6 wt%. The surface morphology of the samples has been examined using an electronic scanning microscope. The results of the wear and fatigue tests indicate that the addition of Al2O3 to the composite enhanced its fatigue resistance and wear strength, with the exception of 6 wt% weight ratio. The best improvement in wear resistance and fatigue strength occurs at 4 wt% Al2O3 particles, which are 12.13 and 67.5%, respectively, more significant than the pure metal and other composites. The mechanical properties of the alloy samples have been enhanced by adding Al2O3 NPs of 25 nm size into the piston’s aluminum matrix alloy. Stir casting was employed to produce the needed composites by incorporating Al2O3 NPs at varied weight percentage ratios of 0, 2, 4, and 6 wt% into the master alloy. Before the composite alloy reached 6 wt%, including Al2O3 NPs, the alloy’s hardness and tensile strength improved, according to the experiment results.

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.

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Monel 400 nickel alloy and AISI 304 austenitic stainless steel dissimilar fusion welding influenced in very important fields like oil, nuclear, space industries and petrochemical where high temperatures and corrosive environments are involved with weldments. Also, this dissimilar joint extremely important with environments demand high heat resistance, corrosion resistance, resistance thermal cycles consequences, creep resistance and good mechanical properties. One of the most important advantages of dissimilar welds is saving of novel and expensive materials cost. Dissimilar welding joints in this research produced with gas tungsten arc welding techniques (GTAW) and ENiCrFe-2 filler. Welding joint configuration simulated welding joint design in real working site to achieved best results and asses real welding site up. SEM/EDS analysis, optical microstructure examination, Vickers microhardness test, tensile test and V-notch impact test employed to study and understand welding microstructure details and properties and its impacts in weldment mechanical properties. Research results reveals formation of partial melting zone (PMZ), unmixed zone (UZ) and second phase in HAZ while dendritic solidification with heat flow direction, epitaxial growth, cellular epitaxial solidification and migrated grain boundaries (MGBs) observed in welding zone microstructure, this research deeply analyses formation of these phenomena, and its effects on weldments mechanical properties were discussed. This research results are very important to welding technologist and engineers to understand and prediction resultant welding zone and HAZ microstructures and understanding its impacts on required weldments design criteria when establish welding procedure.