Exploiting the mechanical properties and optimising wear characteristics of Mg–Al–Zn hybrid composites reinforced with Si3N4 and MoS2

The advancement of lightweight structural materials with enhanced wear resistance continues to be a significant problem for magnesium-based alloys exploited in engineering applications. This research investigates the constraints of mechanical integrity and subpar tribological performance in Mg–Al–Zn alloys by integrating Si 3 N 4 and MoS 2 hybrid reinforcements through a powder metallurgy approach. The effect of reinforcement content on density, hardness, and compressive strength was assessed, and wear behaviour was optimised through a Taguchi L9 orthogonal array to determine the main variables influencing the tribological responses. Three different trials (1–3) were used to analyse the mechanical properties with varied processing parameters, and its microstructure and mechanical properties were analysed as per ASTM standards. The microstructure observation revealed that trial 1 (Mg–Al–Zn alloy + 2 wt% Si 3 N 4 + 2 wt% MoS 2 ) and trial 2 (Mg–Al–Zn alloy + 4 wt% Si 3 N 4 + 2 wt% MoS 2 ) showed Si 3 N 4 and MoS 2 particles agglomerating in the Mg alloy due to lower surface energy, while trial 3 (6 wt% of Si 3 N 4 , 2 wt% of MoS 2 ) exhibited a refined grain structure and acted as nucleation sites for grain refinement during sintering. SEM morphology inferred that the ceramic particles are uniformly distributed in trial 3 comprising of MoS 2 , 510 °C of sintering temperature, 2.5 h soaking time, 550 MPa compaction pressure, improving mechanical properties such as hardness (43.47 ± 0.1%), compressive strength (51.16 ± 0.2%), and corrosion resistance (30.86 ± 0.01%) compared to trials 2, 3, and the Mg–Al–Zn alloy. XRDA confirms that due to higher sintering temperatures, Mg alloy interacts with ceramic particles to form the Mg 2 Si, Mg 3 N 2 interface. The intermixture’s enhanced particle diffusion and bonding resulted in improved corrosion resistance. ANOVA analysis confirmed that Trial 3 confirmed that applied load significantly influences wear rate and CoF, with a contribution exceeding 90% and p < 0.05 in CoF analysis, followed by sliding speed and distance.