## 1 Introduction  
Magnesim and its alloy-based composite are effectively used as matrix material due to their remarkable mechanical properties offering a high strength-to-weight ratio and high damping ratio [1]. Irrespective of superior mechanical properties, low corrosion resistance and high wear rate are often considered major problems when dealing with magnesium alloy as they gradually decrease the strength of magnesium and its alloy [2]. Therefore, the metal matrix composite has low-density magnesium alloy as a matrix reinforced with particles or fibers that involve high stiffness and high resistance to wear along with offering greater strength [3]. The research scenario suggested that the metal matrix composite has carbon-based nanoparticles as a reinforcing agent, enhancing the mechanical properties of the composite [4]. However, the amount of reinforcement in the magnesium alloy matrix is crucial in deciding the uniform composition of nano-powder in the matrix that hinders the crack propagation around the grain boundary and the agglomeration of powder in the composite [5]. The small addition of graphene nanoparticles to the AZ31 alloy significantly improves the mechanical properties and widens its application field, but the uniform dispersion of graphene nanoparticles in the magnesium-based alloy composite is always a challenging task [6]. The mechanical properties of magnesium alloy-based matrix composite depend upon the percentage and types of reinforcement, matrix and fiber composition, fabrication approaches, and processing parameters [7]. The amount of reinforcement is crucial in controlling the porosity of the composites, whereas the types of reinforcement encounter the final characteristics of the composites. Various fabrication approaches are liquid infiltration, stir casting, disintegrated melt deposition, and powder metallurgy [8]. Powder metallurgy (PM) is regarded as the most appropriate method for preparing the magnesium alloy-based composite, involving the high utilization of material with no or less time machining for the final product obtained [9]. The formation of complex shapes with ease is obtained with the help of powder metallurgy via isostatic pressing [10]. [PERSON] et al. observed an improvement in mechanical properties with 0.5 wt.% GNPs in Mg-based matrix composite by powder metallurgy route [11]. [PERSON] et al. [12] investigated the mechanical behavior of Mg-MMCs reinforced with weight fractions (0.2 wt.% to 0.5 wt.%) of r-GO (reduced-graphene oxide) by PM that showed that minimal micro-voids and cracks were established with 0.3 wt.% of r-GO, a clear surface with some micro-voids was obtained with 0.4 wt.% of r-GO, and a large number of cracks were formed with 0.5 wt.% of r-GO, resulting in a decrease in the mechanical characteristics of the composites. [PERSON] et al. [13] analyzed the improvement in elongation and hardness with 0.6 wt.% of GNP in AZ31 alloy matrix composites. [PERSON] et al. [14] fabricated an AZ31 alloy with weight fractions (0.25 to 1 wt.%) of carbon-based reinforcement formed by the powder metallurgy methodology. The microhardness and failure strain were found to be increased by increasing the percentage of reinforcement without any significant change in the tensile strength as compared to the base material. [PERSON] et al. [15] analyzed the fracture mechanism of the AZ31 alloy with a weight fraction (0.33 to 1 wt.%) of carbon-based reinforcement formed by PM. A continuous increase in porosity with a reduction in density was obtained by increasing the amount of carbon-based reinforcing particles in the AZ31 alloy. [PERSON] et al. [16] analyzed the influence of carbon-based reinforcing particles (0.5 to 4 wt.%) on the mechanical characteristics of AZ31 matrix-based composites formed by powder metallurgy. There was a slight increase in porosity from 0.5 to 2 wt.%, but after that, a drastic increase in porosity was observed that led to crack propagation as well as an agglomeration of reinforcement in the matrix material.