Friction and wear performance of aluminum-based self-lubricating materials derived from the 3D printed graphite skeletons with different morphologies and orientations

Using selective laser sintering 3D printing, this study shapes graphite in sphere, flake, and fiber morphologies into skeletons with various orientations. These skeletons are then used to create graphite/aluminum alloy composite self-lubricating materials. The results show that graphite morphology and orientation greatly affect the friction and wear properties of these composites. Graphite fiber exhibits the worst friction and wear performance. Perpendicular flake graphite forms a uniform, continuous lubricating film with high thermal conductivity for heat dissipation, preventing severe wear. Spherical graphite modifies the friction surface, achieving the lowest friction coefficient (0.2±0.02) and wear rate (6.64×10-4mm3/Nm) due to protective film, filling, and ball bearing effects.