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Mechanical alloying is a solid-state powder metallurgy technology that includes high-energy ball milling to repeatedly deform, fracture, and weld powder particles. This method is capable of being used to produce metal alloys, intermetallics, and composites with controlled microstructures and enhanced properties including hardness, strength, and wear resistance. Mechanical alloying is employed in a variety of fields, including aerospace, automotive, and biomedical engineering, as well as the development of novel materials for energy storage and conversion [10; 11; 12; 13]. Powder metallurgy includes the process of sintering metal components, which comprises a variety of stages such as powder preparation, mixing, compacting, and sintering. Consolidation, in which the powder particles are pressed together to generate a solid mass, is a crucial stage in this process. The ultimate properties of the metal component, such as strength, density, and porosity, are influenced by the consolidation process. Consolidation can be achieved using a variety of processes, including cold pressing, hot pressing, and isostatic pressing, depending on the kind of metal powder and the required characteristics of the final product [14; 15; 16; 17]. The properties of aluminum alloys must be improved in order to be suitable for the aerospace and automotive sectors, particularly at moderately increased temperatures. To accomplish this, alternative alloying systems, such as aluminum-based alloys containing trace amounts of transition metals such as chromium, molybdenum, zirconium, and iron, are being extensively investigated [18]. Even at low concentrations, chromium has a significant influence on recrystallization in commercial wrought aluminum alloys. Higher chromium concentrations, on the other hand, cannot be produced using traditional casting and ingot metallurgy due to detrimental effects on toughness, strength, and formability. As a result, powder metallurgy is employed in their manufacture, which involves powder preparation using melt atomization or mechanical alloying, followed by powder compaction via hot extrusion. Powder metallurgy produces Al-TM alloys with a refined and homogenous structure, which improves their strength and thermal stability [18; 19; 20; 21]. Polycrystalline metals and alloys' mechanical properties are highly sensitive to grain size. It has been widely established that refining the grain size of a polycrystalline material can substantially increase its strength. [PERSON] [22] and [PERSON] [23] developed an important relationship, known as the Hall-Petch relationship, between the yield strength and grain size d of polycrystals. The mechanical properties of nanocrystalline alloys or metals are greatly affected by grain size. Decreasing grain size results in a higher density of grain boundaries, which improves hardness, strength, and ductility. Although the high density of grain boundariesfavors tensile strength, grain boundaries could also serve as a location for fracture initiation, resulting in a loss in ductility. To achieve the right combination of mechanical properties in nanocrystalline alloys or metals, rigorous optimization of grain size, composition, and processing conditions is required [24; 25; 26]. Thus, the aim of this study is to investigate the benefits of applying powder metallurgy to produce Al5 Cr- and Al7.5 Cr-consolidated samples. In this regard, Al-Cr powder blends were mechanically milled and then consolidated to explore the effect of non-equilibrium processing parameters on micro-structural features such as crystallite size, lattice strain, dislocation density, and solid-phase transitions. A theoretical model was developed as well to predict some mechanical properties of the materials produced in this work. Microstructural characteristics such as porosity, volume fraction, and precipitate volume fraction were considered in this model.