###### Abstract  
Aluminium metal matrix composites have been shown to make significant contributions to the area of new materials and have become widely accepted in high-tech structural and functional applications such as those in the aircraft, automobile, marine, mineral, defence, transportation, thermal management, automotive, and sports and recreation fields. Metal matrix composites are manufactured using a variety of manufacturing processes. Stirring casting, powder metallurgy, squeezing casting, in situ processes, deposition techniques, and electroplating are part of the manufacturing process used in the manufacture of aluminium-metal matrix composites. Metal matrix composites that use friction stir processing have a distinct advantage over metal matrix composites that use other manufacturing techniques. FSP's benefits include a finer grain, processing zone homogeneity, densification, and the homogenization of aluminium alloy and composite precipitates. Most metal matrix composite investigations achieve aluminium-metal matrix composite precipitate grain refinement, treated zone homogeneity, densification, and homogenization. This part of the work examines the impact of reinforcing particles, process parameters, multiple passes, and active cooling on mechanical properties during the fabrication of 5000-series aluminium-metal matrix composites using friction stir processing. This paper reports on the available literature on aluminium metal matrix composites fabricated with 5 xxx series marine grade aluminium alloy using FSP. aluminium 5 xxx series; marine grades; friction stir welding; friction stir processing; composite; metal matrix composite +
Footnote †: journal: Applied Sciences  
10 December 2022  
14 December 2022  
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**1. Introduction**  
Aluminium alloys have exceptional flexibility and applicability, along with multiple benefits (corrosion resistance, strength, and workability), making them suitable for a variety of goods and markets [1]. Naval architects and ocean engineers have recognized aluminium and its alloys as very favourable materials for marine and offshore structures [2]. The improved, lighter-weight mechanical properties and corrosion resistance of aluminium alloys have made many of these applications possible. Naval architects can use aluminium to build boats that have a longer life, a high recycling value, minimal maintenance costs, higher payloads, and high-speed capability [3]. In shipbuilding, several marine AAs are used to fabricate various sections, such as hulls, superstructures, decks, and bulkheads. Aluminium and its alloys provide significant benefits in terms of hull maintenance and structural weight reduction [4]. The 5 xxx series of aluminium magnesium alloys, one of the most significant series of aluminium alloys, have found wide use in the automotive and transportation sectors, aerospace aluminium panels, and marine applications due to their advantageous properties, particularly corrosion resistance and weldability [5, 6, 7]. Aluminium alloys from the 5 xxx series have appropriate corrosion-resistance properties and strength, making them popular materials for decks, ship-hull constructions, corrosive environments, superstructures, and other components [8; 9] and are used in many maritime constructions, including boats, cargos, ferries, and ships. The comparably low strength of the 5 xxx series Al-Mg alloys, however, restricts their use. Precipitation hardening will not strengthen this alloy because it is a non-heat-treatable alloy. The last strengthening procedures for this alloy include work hardening, dispersion strengthening, and grain-refinement strengthening. The creation of aluminium metal matrix composites (AMCs) utilizing the dispersion strengthening effect is one of the most promising techniques for strengthening this type of Al-Mg alloy. Aluminium metal matrix composites are significant contributions to the area of new materials.