On 3D Printed Sandwich Meta-structures for Improved Wear Characteristics

The direct metal laser sintering (DMLS) based functionally graded material (FGM) has numerous structural and non-structural applications. However, little has been reported on tuning the wear characteristics of these FGM. This study presents the wear characteristics comparison of the 3D-printed sandwich meta-structures (as FGM) with DMLS. For comparative analysis, two different 3D printed meta-structures (Phelan and Dodecahedron) of Ni-625 alloy were sandwiched between 17-4 precipitate-hardened (PH) stainless steel (SS) layers by DMLS in this study. The result highlights that Dodecahedron meta-structure of Ni-625 has better wear characteristics than Phelan (23.8% at 20N applied load (AL), operating time (OT) 5 min, operational speed (OS) 200 RPM, 17.5% at 30N AL, OT10 min, OS 300 RPM, 41.61% at 40N AL, OT 15 min, OS 400 RPM) due to less volume/unit crystal. As regards surface characteristics, the surface roughness (Ra) of the sandwich layer with Dodecahedron meta-structure has shown 7.25%, and 5.85% improvement than Phelan before and after wear respectively. The results are also supported by morphological analysis.