Abstract
Surplus out-of-spec Al powders, typically discarded, remain an underused resource. Their reuse via alternative consolidation routes is a sustainable path for AlSi10Mg alloy recycling, but studies on the feasibility of such routes remain scarce. This study proposes a novel route combining powder compaction (under 50 kN and 80 kN loads) and remelting/solidification via suction casting to assess the feasibility of producing dense parts with enhanced properties. Microstructure, mechanical properties (compression and Vickers microhardness), and tribological performance (ball-crater wear under dry and abrasive conditions) were evaluated. The proposed route produced dense AlSi10Mg parts with low porosity levels (≤0.2%) and refined dendritic microstructures (spacing between 2.4 and 4.6 µm). Increased cooling rates promoted microstructural refinement, while higher compaction loads improved densification. The refined microstructure samples achieved compressive strengths above 500 MPa. Remarkably, microstructural refinement led to significantly increased hardness, with values reaching ≥100 HV. The samples compacted at 50 kN and subjected to the highest cooling rate exhibited the lowest dry wear rate (2.3 × 10−4 mm3/N·m), comparable to additively manufactured AlSi10Mg (AM) samples, confirming the efficiency of this recycling route. The dry wear rates ranged from 2.3 to 3.9 × 10−4 mm3/N·m, reinforcing the inverse correlation between hardness and dry wear performance. Although abrasive wear resulted in a material loss approximately 3 times higher than dry wear, it preserved the same microstructural dependence: finer, harder, and denser samples exhibited better wear resistance.