The use of aluminum alloys, nowadays, is swiftly growing from the prerequisite of producing higher strength to weight ratio. Lightweight components are crucial interest in most manufacturing sectors, especially in transportation, aviation, maritime, automotive, and others. Traditional available joining methods have an adverse effect on joining these lightweight engineering materials, increasing needs for new environmentally friendly joining methods. Hence, friction stir welding (FSW) is introduced. Friction stir welding is a relatively new welding process that can produce high-quality weld joints with a lightweight and low joining cost with no waste. This paper endeavors to deals with optimizing process parameters for quality criteria on tensile and hardness strengths. Samples were taken from a 5 mm 6061-T6 aluminum alloy sheet with butt joint configuration. Controlled process parameters tool profile, rotational speed and transverse speed were utilized. The process parameters are optimized making use of the combination of Grey relation analysis method and L₉ orthogonal array. Mechanical properties of the weld joints are examined through tensile, hardness, and liquid penetrant tests at room temperature. From this research, rotational speed and traverse speed become significant parameters at a 99% confidence interval, and the joint efficiency reached 91.3%.

Materials are one of the basic elements or needs for continuing human beings’ life living and they are used for structural and nonstructural, biomedical, thermal, or other applications. In many types of materials, Composite materials are used in different sectors. The increasing need for eco-friendly, low-density, and lightweight product production prompted the development of fiber-reinforced polymer composites for usage in a variety of home items and automobile parts. The automobile manufacturing sectors have recently attempted to manufacture lighter and lighter parts. Shortly, automobiles must be lighter to meet demands for lower fuel usage and fewer CO2 emissions. On the other side that textile waste is still simply thrown into a landfill in the environment resulting in and causing pollution. So, the objective of this review was to show the ability of these waste materials used as reinforcing material for composite fabrication products like car hoods, Car bumpers, and lightweight automotive parts. also, it tries to explain the roles of lightweight materials for automotive body parts and also the reduction of wastes in the textile industry by recycling and converting them into useable products, making the environment free of pollution. This waste reduction is a current world issue.

Advancements in engineering technologies are fundamentally driven by the development of superior materials with tailored properties to meet stringent application demands. Metal matrix composites (MMCs) have emerged as essential solutions for such customization. This study presents the synthesis and optimization of Al7039/Cu/SiC MMCs to significantly enhance thermal conductivity and hardness using Response Surface Methodology (RSM). The composites were fabricated by combining aluminum 7039 alloy with high-purity copper (99.98%) and reinforcing them with silicon carbide (SiC) particles. Specimens were efficiently produced using a cost-effective stir casting method with silica sand shell molds using an induction melting furnace. The optimization process involved varying the weight fractions of Al7039 (73%–91%), Cu (4%–12%), and SiC (5%–15%) across 20 experimental runs. Hardness and thermal conductivity were measured using a Rockwell B tester and steady-state linear testing, respectively. Analysis of variance (ANOVA) confirmed that weight fraction variations significantly influenced the measured properties. Statistically significant quadratic models were developed, exhibiting less than 5% variation at a 95% confidence level. Numerical optimization indicated that decreasing Al7039 content while increasing Cu and SiC fractions maximizes thermal conductivity and hardness. This process identified 34 viable solutions, with the optimal composition being 69.22 wt% Al7039, 12 wt% Cu, and 15 wt% SiC. This formulation achieved a thermal conductivity of 167.2 W/m. K and a hardness of 186.1 BHN, corresponding to a desirability score of 0.859 (86%). For robust validation, experiments were meticulously conducted in triplicate using the same procedures and equipment as in the predictive modeling. The experimental results closely matched the predicted values, yielding 169.6 W/m. K and 190.4 BHN improvements of 17.5% and 30% in thermal conductivity and hardness over the base Al7039 alloy, respectively. The optimized Al7039/Cu/SiC composites exhibit significant enhancements over the base alloy, offering excellent properties suitable for demanding applications such as heat sinks, heat exchangers, mold tooling, and critical components in the automotive and aerospace sectors. This study emphasizes the potential of optimized MMCs to efficiently and cost-effectively fulfill advanced engineering requirements, promoting their adoption in innovative technologies.